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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-Q
☑ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended September 30, 2025
or
☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from to
Commission file number 001-16189
NiSource Inc.
(Exact name of registrant as specified in its charter)

DE |  | 35-2108964
(State or other jurisdiction of incorporation or organization) |  | (I.R.S. Employer Identification No.)
801 East 86th Avenue |  |
Merrillville, | IN |  | 46410
(Address of principal executive offices) |  | (Zip Code)

(877) 647-5990
(Registrant’s telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class | Trading Symbol(s) | Name of Each Exchange on Which Registered
Common Stock, par value $0.01 per share | NI | NYSE

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
Yes þ No ¨
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files.)
Yes þ No ¨
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer þ Accelerated filer ¨ Emerging growth company ☐ Non-accelerated filer ¨ Smaller reporting company ☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).
Yes ☐ No ☑
Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date: Common Stock, $0.01 Par Value: 477,195,529 shares outstanding at October 22, 2025.

NISOURCE INC.
FORM 10-Q QUARTERLY REPORT
FOR THE QUARTER ENDED SEPTEMBER 30, 2025
Table of Contents

|  |  | Page
| Defined Terms | 3
PART I | FINANCIAL INFORMATION |
| Item 1. | Financial Statements - unaudited |
|  | Condensed Statements of Consolidated Income (unaudited) | 9
|  | Condensed Statements of Consolidated Comprehensive Income (unaudited) | 10
|  | Condensed Consolidated Balance Sheets (unaudited) | 11
|  | Condensed Statements of Consolidated Cash Flows (unaudited) | 13
|  | Condensed Statements of Consolidated Equity (unaudited) | 14
|  | Notes to Condensed Consolidated Financial Statements (unaudited) | 17
| Item 2. | Management’s Discussion and Analysis of Financial Condition and Results of Operations | 43
| Item 3. | Quantitative and Qualitative Disclosures About Market Risk | 67
| Item 4. | Controls and Procedures | 67
PART II | OTHER INFORMATION |
| Item 1. | Legal Proceedings | 68
| Item 1A. | Risk Factors | 68
| Item 2. | Unregistered Sales of Equity Securities and Use of Proceeds | 71
| Item 3. | Defaults Upon Senior Securities | 71
| Item 4. | Mine Safety Disclosures | 71
| Item 5. | Other Information | 71
| Item 6. | Exhibits | 73
| Signature | 74

2

DEFINED TERMS |
The following is a list of frequently used abbreviations or acronyms that are found in this report: |
NiSource Subsidiaries and Affiliates (not exhaustive) |
Columbia of Kentucky | Columbia Gas of Kentucky, Inc. |
Columbia of Maryland | Columbia Gas of Maryland, Inc. |
Columbia of Ohio | Columbia Gas of Ohio, Inc. |
Columbia of Pennsylvania | Columbia Gas of Pennsylvania, Inc. |
Columbia of Virginia | Columbia Gas of Virginia, Inc. |
GenCo | NIPSCO Generation LLC |
Generation Holdings I | Generation Holdings I LLC |
Generation Holdings II | Generation Holdings II LLC |
NIPSCO | Northern Indiana Public Service Company LLC |
NIPSCO Holdings I | NIPSCO Holdings I LLC |
NIPSCO Holdings II | NIPSCO Holdings II LLC |
NiSource ("we," "us" or "our") | NiSource Inc. |
Rosewater | Rosewater Wind Generation LLC and its wholly owned subsidiary, Rosewater Wind Farm LLC |
Indiana Crossroads Wind | Indiana Crossroads Wind Generation LLC and its wholly owned subsidiary, Indiana Crossroads Wind Farm LLC |
Indiana Crossroads Solar | Indiana Crossroads Solar Generation LLC and its wholly owned subsidiary, Meadow Lake Solar Park LLC |
Dunns Bridge I | Dunn's Bridge I Solar Generation LLC and its wholly owned subsidiary, Dunns Bridge Solar Center, LLC |
Gibson | Gibson Solar LLC |
Fairbanks | Fairbanks Solar Energy Center LLC |
Abbreviations and Other |  |
AFUDC | Allowance for funds used during construction |
Amended LLC Agreement | Third Amended and Restated Limited Liability Company Agreement of NIPSCO Holdings II |
AOCI | Accumulated Other Comprehensive Income (Loss) |
ASC | Accounting Standards Codification |
ASU | Accounting Standards Update |
ATM | At-the-market |
BIP | BIP Blue Buyer L.L.C |
BIP Blue Buyer VCOC L.L.C | BIP Blue Buyer VCOC L.L.C., a Delaware limited liability company and also an affiliate of Blackstone |
BIP Orion Holdco L.P. | BIP Orion Holdco L.P., a Delaware limited liability company and also an affiliate of Blackstone |
BIP Orion Holdco II L.P. | BIP Orion Holdco II L.P., a Delaware limited liability company and also an affiliate of Blackstone |
Blackstone | Blackstone Infrastructure Partners L.P. |
BTA | Build-transfer agreement |
Contract Assets | Generation assets and related transmission infrastructure to be developed in connection with the Data Center Contract |
CCRs | Coal Combustion Residuals |
CEP | Ohio Capital Expenditure Program |
CERCLA | Comprehensive Environmental Response Compensation and Liability Act (also known as Superfund) |

3

DEFINED TERMS |
CODM | Chief Operating Decision Maker |
Columbia Operations | Reportable segment comprised of the results of NiSource Gas Distribution company, including all of its Columbia Gas distribution companies and related subsidiaries |
CPCN | Certificate of Public Convenience and Necessity |
Customer | Purchaser of electricity under Data Center Contract, a wholly-owned subsidiary of a large publicly traded company |
Data Center Contract | NIPSCO agreement to provide electricity to Customer’s data centers |
DSIC | Distribution System Improvement Charge |
DSM | Demand Side Management |
Dunns Bridge II | Dunns Bridge II Solar Generation Center |
EPA | United States Environmental Protection Agency |
EPC | Engineering, procurement, and construction |
EPS | Earnings per share |
ERP | Enterprise Resource Planning |
FAC | Fuel adjustment clause |
FASB | Financial Accounting Standards Board |
FMCA | Indiana Federally Mandated Cost Adjustment mechanism |
GAAP | Generally Accepted Accounting Principles |
GCA | Gas cost adjustment |
Generation Assets | Power generations facilities and battery storage to be developed in connection with the Data Center Contract |
GHG | Greenhouse gases |
GWh | Gigawatt hours |
IRA | Inflation Reduction Act of 2022 |
IRP | Ohio Infrastructure Replacement Program |
IURC | Indiana Utility Regulatory Commission |
Investor | BIP Orion Holdco L.P. and BIP Orion Holdco II L.P. in connection with Blackstone's GenCo minority equity investment |
JV | Joint Venture |
LIFO | Last In, First Out |
LIHEAP | Low Income Heating Energy Assistance Program |
LLC Agreement | Amended and Restated Limited Liability Company Agreement of Generation Holdings II |
MGP | Manufactured Gas Plant |
MISO | Midcontinent Independent System Operator |
MMDth | Million dekatherms |
MW | Megawatts |
MWh | Megawatt hours |
NIPSCO Electric | The electric generation and transmission activities of the NIPSCO Operations reportable segment |
NIPSCO Gas | The gas distribution activities of the NIPSCO Operations reportable segment |
NIPSCO Minority Interest Transaction | A transaction between NiSource, NIPSCO Holdings II (sole owner of NIPSCO) and an affiliate of Blackstone pursuant to a purchase and sale agreement entered into on June 17, 2023, that offered equity interests in NIPSCO Holdings II in exchange for capital contributions by the parties. |
NIPSCO Operations | Reportable segment comprised of the results of NIPSCO Holdings I, NIPSCO Holdings II, and NIPSCO and all related subsidiaries |

4

DEFINED TERMS |
NYMEX | New York Mercantile Exchange |
OPEB | Other Postemployment Benefits |
PHMSA | Pipeline and Hazardous Materials Safety Administration |
PPA | Power Purchase Agreement |
RNG | Renewable Natural Gas |
SAVE | Steps to Advance Virginia's Energy Plan |
Scope 1 GHG Emissions | Direct emissions from sources owned or controlled by us (e.g., emissions from our combustion of fuel, vehicles, and process emissions and fugitive emissions) |
Scope 2 GHG Emissions | Indirect emissions from sources owned or controlled by us |
SEC | Securities and Exchange Commission |
SMRP | Kentucky Safety Modification and Replacement Program |
SMS | Safety Management System |
TCJA | An Act to provide for reconciliation pursuant to titles II and V of the concurrent resolution on the budget for fiscal year 2018 (commonly known as the Tax Cuts and Jobs Act of 2017) |
TDSIC | Indiana Transmission, Distribution and Storage System Improvement Charge |
Templeton | Templeton Wind Energy Center |
VIE | Variable Interest Entity |
WAM | Work and Asset Management enterprise resourcing system |

Note regarding forward-looking statements
This Quarterly Report on Form 10-Q contains "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Investors and prospective investors should understand that many factors govern whether any forward-looking statement contained herein will be or can be realized. Any one of those factors could cause actual results to differ materially from those projected. These forward-looking statements include, but are not limited to, statements concerning our plans, strategies, objectives, expected performance, expenditures, recovery of expenditures through rates, stated on either a consolidated or segment basis, and any and all underlying assumptions and other statements that are other than statements of historical fact. Expressions of future goals and expectations and similar expressions, including "may," "will," "should," "could," "would," "aims," "seeks," "expects," "plans," "anticipates," "intends," "believes," "estimates," "predicts," "potential," "targets," "forecast," and "continue," reflecting something other than historical fact are intended to identify forward-looking statements. All forward-looking statements are based on assumptions that management believes to be reasonable; however, there can be no assurance that actual results will not differ materially.
Factors that could cause actual results to differ materially from the projections, forecasts, estimates and expectations discussed in this Quarterly Report on Form 10-Q include, among other things:
•our ability to execute our business plan or growth strategy, including utility infrastructure investments, or business opportunities, such as data center development and related generation sources and transmission capabilities to meet potential load growth;
•our ability to manage data center growth in our service territories;
•potential incidents and other operating risks associated with our business;
•our ability to work successfully with our third-party investors;
•our ability to construct, develop and place into service the Contract Assets on time or at all and consistent with initial cost estimates, as well as the performance of these assets once constructed and placed into service;
•our ability to obtain the significant additional financing that will be required to construct the Contract Assets on favorable terms, if at all;
•our ability to recover our investments and realize our expected return under the Data Center Contract;
5

•our ability to maintain our investment grade credit ratings as we finance and pursue our data center strategy, including our performance under the Data Center Contract;
•our Customer’s performance under the Data Center Contract and any decision by the Customer to terminate the Data Center Contract or reduce the committed capacity thereunder;
•potential changes in the MISO accreditation treatment of capacity resources;
•our ability to adapt to, and manage costs related to, advances in technology, including alternative energy sources and changes in laws and regulations;
•our increased dependency on technology;
•impacts related to our aging infrastructure;
•our ability to obtain sufficient insurance coverage and whether such coverage will protect us against significant losses;
•the success of our electric generation strategy;
•construction risks and supply risks;
•fluctuations in demand from residential and commercial customers;
•fluctuations in the price of energy commodities and related transportation costs or an inability to obtain an adequate, reliable and cost-effective fuel supply to meet customer demand;
•our ability to attract, retain or re-skill a qualified, diverse workforce and maintain good labor relations;
•our ability to manage new initiatives and organizational changes;
•the performance and quality of third-party suppliers and service providers;
•our ability to manage the financial and operational risks related to achieving our carbon emission reduction goals, including our Net Zero Goal (as defined below), including any future associated impact from business opportunities such as data center development as those opportunities evolve;
•potential cybersecurity attacks or security breaches;
•increased requirements and costs related to cybersecurity;
•the actions of activist stockholders;
•any damage to our reputation;
•the impacts of natural disasters, potential terrorist attacks or other catastrophic events;
•the physical impacts of climate change and the transition to a lower carbon future;
•our debt obligations;
•any changes to our credit rating or the credit rating of certain of our subsidiaries;
•adverse economic and capital market conditions, including increases in inflation or interest rates, recession, or changes in investor sentiment;
•economic regulation and the impact of regulatory rate reviews;
•our ability to obtain expected financial or regulatory outcomes;
•economic conditions in certain industries;
•the reliability of customers and suppliers to fulfill their payment and contractual obligations;
•the ability of our subsidiaries to generate cash;
•pension funding obligations;
•potential impairments of goodwill;
•the outcome of legal and regulatory proceedings, investigations, incidents, claims and litigation;
•compliance with changes in, or new interpretations of applicable laws, regulations and tariffs, including impacts of state and federal orders on our ability to carry out our business plan and growth strategy;
•the cost of compliance with environmental laws and regulations and the costs of associated liabilities;
•changes in tax laws or the interpretation thereof;
•and other matters set forth in Part I, Item 2, “Management’s Discussion and Analysis of Financial Condition and Results of Operation,” and Part II, Item 1A, “Risk Factors,” of this report, and Part I, Item 1, “Business,” Part I, Item 1A, "Risk Factors," and Part II, Item 7, "Management’s Discussion and Analysis of Financial Condition and Results of Operations," of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, some of which risks are beyond our control.
6

In addition, the relative contributions to profitability by each business segment, and the assumptions underlying the forward-looking statements relating thereto, may change over time.
All forward-looking statements are expressly qualified in their entirety by the foregoing cautionary statements. We undertake no obligation to, and expressly disclaim any such obligation to, update or revise any forward-looking statements to reflect changed assumptions, the occurrence of anticipated or unanticipated events or changes to the future results over time or otherwise, except as required by law.
7

Index | Page
Condensed Statements of Consolidated Income (unaudited) | 9
Condensed Statements of Consolidated Comprehensive Income (unaudited) | 10
Condensed Consolidated Balance Sheets (unaudited) | 11
Condensed Statements of Consolidated Cash Flows (unaudited) | 13
Condensed Statements of Consolidated Equity (unaudited) | 14
Notes to Condensed Consolidated Financial Statements (unaudited) | 17
1. Basis of Accounting Presentation | 17
2. Recent Accounting Pronouncements | 17
3. Revenue Recognition | 18
4. Noncontrolling Interests | 22
5. Earnings Per Share | 23
6. Equity | 24
7. Short-Term Borrowings | 25
8. Long-Term Debt | 25
9. Regulatory Matters | 26
10. Risk Management Activities | 26
11. Fair Value | 28
12. Income Taxes | 31
13. Pension and Other Postemployment Benefits | 32
14. Other Commitments and Contingencies | 33
15. Accumulated Other Comprehensive Loss | 36
16. Business Segment Information | 37
17. Other, Net | 40
18. Supplemental Disclosures of Cash Flow Information | 41
19. Subsequent Event | 42

8

Table of Contents
PART I
ITEM 1. FINANCIAL STATEMENTS
NiSource Inc.
Condensed Statements of Consolidated Income (unaudited)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions, except per share amounts) | 2025 |  | 2024 |  | 2025 |  | 2024
Operating Revenues |  |  |  |  |  |
Customer revenues | $ | 1,240.2 |  |  | $ | 1,046.1 |  |  | $ | 4,636.2 |  |  | $ | 3,743.2 |
Other revenues | 32.9 |  |  | 30.2 |  |  | 103.1 |  |  | 124.1 |
Total Operating Revenues | 1,273.1 |  |  | 1,076.3 |  |  | 4,739.3 |  |  | 3,867.3 |
Operating Expenses |  |  |  |  |  |  |
Cost of energy | 193.6 |  |  | 165.9 |  |  | 1,102.9 |  |  | 755.6 |
Operation and maintenance | 401.1 |  |  | 357.4 |  |  | 1,225.1 |  |  | 1,093.5 |
Depreciation and amortization | 306.9 |  |  | 269.5 |  |  | 852.2 |  |  | 765.1 |
Loss on impairment of assets | — |  |  | — |  |  | 0.7 |  |  | 2.9 |
Loss (gain) on sale of assets, net | (0.6) |  |  | (0.5) |  |  | 0.2 |  |  | 1.1 |
Other taxes | 74.6 |  |  | 65.7 |  |  | 238.4 |  |  | 210.4 |
Total Operating Expenses | 975.6 |  |  | 858.0 |  |  | 3,419.5 |  |  | 2,828.6 |
Operating Income | 297.5 |  |  | 218.3 |  |  | 1,319.8 |  |  | 1,038.7 |
Other Income (Deductions) |  |  |  |  |  |  |
Interest expense, net | (179.8) |  |  | (134.6) |  |  | (451.7) |  |  | (380.2) |
Other, net | 9.9 |  |  | 29.2 |  |  | 16.2 |  |  | 51.4 |
Total Other Deductions, Net | (169.9) |  |  | (105.4) |  |  | (435.5) |  |  | (328.8) |
Income before Income Taxes | 127.6 |  |  | 112.9 |  |  | 884.3 |  |  | 709.9 |
Income Taxes | 20.6 |  |  | 15.9 |  |  | 150.1 |  |  | 109.5 |
Net Income | 107.0 |  |  | 97.0 |  |  | 734.2 |  |  | 600.4 |
Net income attributable to noncontrolling interest | 12.3 |  |  | 11.3 |  |  | 62.5 |  |  | 63.9 |
Net Income Attributable to NiSource | 94.7 |  |  | 85.7 |  |  | 671.7 |  |  | 536.5 |
Preferred dividends | — |  |  | — |  |  | — |  |  | (6.7) |
Preferred redemption premium | — |  |  | — |  |  | — |  |  | (14.0) |
Net Income Available to Common Shareholders | $ | 94.7 |  |  | $ | 85.7 |  |  | $ | 671.7 |  |  | $ | 515.8 |
Earnings Per Share |  |  |  |  |  |  |
Basic Earnings Per Share | $ | 0.20 |  |  | $ | 0.19 |  |  | $ | 1.42 |  |  | $ | 1.15 |
Diluted Earnings Per Share | $ | 0.20 |  |  | $ | 0.19 |  |  | $ | 1.42 |  |  | $ | 1.14 |
Basic Average Common Shares Outstanding | 472.1 |  |  | 451.9 |  |  | 471.1 |  |  | 449.4 |
Diluted Average Common Shares | 473.7 |  |  | 454.5 |  |  | 472.8 |  |  | 451.4 |

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
9

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Condensed Statements of Consolidated Comprehensive Income (unaudited)

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions, net of taxes) | 2025 |  | 2024 |  | 2025 |  | 2024
Net Income | $ | 107.0 |  |  | $ | 97.0 |  |  | $ | 734.2 |  |  | $ | 600.4 |
Other comprehensive income: |  |  |  |  |  |  |
Net unrealized gain on available-for-sale debt securities(1) | 1.3 |  |  | 3.5 |  |  | 3.1 |  |  | 3.2 |
Reclassification adjustment for cash flow hedges(2) | (0.1) |  |  | (0.1) |  |  | (0.3) |  |  | (0.3) |
Unrecognized pension and OPEB benefit(3) | 14.0 |  |  | 0.6 |  |  | 14.6 |  |  | 1.1 |
Total other comprehensive income | 15.2 |  |  | 4.0 |  |  | 17.4 |  |  | 4.0 |
Comprehensive Income | $ | 122.2 |  |  | $ | 101.0 |  |  | $ | 751.6 |  |  | $ | 604.4 |

(1)Net unrealized gain on available-for-sale debt securities, net of $0.3 million tax expense and $0.9 million tax expense in the third quarter of 2025 and 2024, respectively, and $0.8 million tax expense for the nine months ended 2025 and 2024, respectively.
(2)Reclassification adjustment for cash flow hedges, net of $0.1 million tax benefit and $0.1 million tax benefit in the third quarter of 2025 and 2024, respectively, and $0.2 million tax benefit and $0.1 million tax benefit for the nine months ended 2025 and 2024, respectively.
(3)Unrecognized pension and OPEB benefit, net of $4.6 million tax expense and $0.2 million tax expense in the third quarter of 2025 and 2024, respectively, and $4.8 million tax expense and $0.4 million tax expense for the nine months ended 2025 and 2024, respectively.
The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
10

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Condensed Consolidated Balance Sheets (unaudited)

(in millions) | September 30, 2025 |  | December 31, 2024
ASSETS |  |  |
Property, Plant and Equipment |  |  |
Plant | $ | 37,201.7 |  |  | $ | 34,152.9 |
Accumulated depreciation and amortization | (9,201.6) |  |  | (8,699.0) |
Net Property, Plant and Equipment(1) | 28,000.1 |  |  | 25,453.9 |
Investments and Other Assets |  |  |
Unconsolidated affiliates | 7.7 |  |  | 6.5 |
Available-for-sale debt securities (amortized cost of $160.4 and $91.9, allowance for credit losses of $0.1 and $0.1, respectively) | 159.0 |  |  | 86.7 |
Other investments | 116.2 |  |  | 85.5 |
Total Investments and Other Assets | 282.9 |  |  | 178.7 |
Current Assets |  |  |
Cash and cash equivalents | 95.0 |  |  | 156.6 |
Restricted cash | 24.5 |  |  | 42.0 |
Accounts receivable | 719.6 |  |  | 987.9 |
Allowance for credit losses | (18.6) |  |  | (23.7) |
Accounts receivable, net | 701.0 |  |  | 964.2 |
Gas storage | 268.3 |  |  | 179.6 |
Materials and supplies, at average cost | 183.3 |  |  | 173.3 |
Electric production fuel, at average cost | 23.7 |  |  | 36.2 |
Exchange gas receivable | 42.9 |  |  | 45.7 |
Regulatory assets | 326.5 |  |  | 319.9 |
Prepayments | 157.4 |  |  | 138.5 |
Other current assets | 25.6 |  |  | 24.2 |
Total Current Assets(1) | 1,848.2 |  |  | 2,080.2 |
Other Assets |  |  |
Regulatory assets | 2,132.9 |  |  | 2,157.4 |
Goodwill | 1,485.9 |  |  | 1,485.9 |
Deferred charges and other | 652.9 |  |  | 432.0 |
Total Other Assets | 4,271.7 |  |  | 4,075.3 |
Total Assets | $ | 34,402.9 |  |  | $ | 31,788.1 |

(1)Includes $1,284.4 million and $1,323.8 million at September 30, 2025 and December 31, 2024, respectively, of net property, plant and equipment assets and $59.6 million and $65.0 million at September 30, 2025 and December 31, 2024, respectively, of current assets of consolidated VIEs that may be used only to settle obligations of the consolidated VIEs. Refer to Note 4, "Noncontrolling Interests," for additional information.
The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
11

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Condensed Consolidated Balance Sheets (unaudited) (continued)

(in millions, except share amounts) | September 30, 2025 |  | December 31, 2024 |
CAPITALIZATION AND LIABILITIES |  |  |  |
Capitalization |  |  |  |
Stockholders’ Equity |  |  |  |
Common stock - $0.01 par value,750,000,000 shares authorized; 477,136,079 and 469,822,472 shares outstanding, respectively | $ | 4.8 |  |  | $ | 4.7 |  |
Treasury stock | (99.9) |  |  | (99.9) |  |
Additional paid-in capital | 9,798.3 |  |  | 9,521.5 |  |
Retained deficit | (572.0) |  |  | (711.7) |  |
Accumulated other comprehensive loss | (13.0) |  |  | (30.4) |  |
Total NiSource Stockholders’ Equity | 9,118.2 |  |  | 8,684.2 |  |
Noncontrolling interest in consolidated subsidiaries | 2,123.6 |  |  | 1,984.1 |  |
Total Stockholders’ Equity | 11,241.8 |  |  | 10,668.3 |  |
Long-term debt, excluding amounts due within one year | 14,472.1 |  |  | 12,074.5 |  |
Total Capitalization | 25,713.9 |  |  | 22,742.8 |  |
Current Liabilities |  |  |  |
Current portion of long-term debt | 31.3 |  |  | 1,281.2 |  |
Short-term borrowings | 1,260.0 |  |  | 604.6 |  |
Accounts payable | 712.0 |  |  | 863.1 |  |
Dividends payable - common stock | 137.4 |  |  | — |  |
Customer deposits and credits | 273.5 |  |  | 268.8 |  |
Taxes accrued | 179.0 |  |  | 173.4 |  |
Interest accrued | 198.2 |  |  | 157.0 |  |
Asset retirement obligations | 66.3 |  |  | 84.6 |  |
Exchange gas payable | 100.0 |  |  | 91.8 |  |
Regulatory liabilities | 192.0 |  |  | 150.5 |  |
Accrued compensation and employee benefits | 218.0 |  |  | 268.2 |  |
Other accruals | 165.7 |  |  | 170.2 |  |
Total Current Liabilities(1) | 3,533.4 |  |  | 4,113.4 |  |
Other Liabilities |  |  |  |
Deferred income taxes | 2,405.4 |  |  | 2,281.6 |  |
Accrued liability for postretirement and postemployment benefits | 174.4 |  |  | 207.5 |  |
Regulatory liabilities | 1,487.0 |  |  | 1,431.2 |  |
Asset retirement obligations | 751.4 |  |  | 698.6 |  |
Other noncurrent liabilities and deferred credits | 337.4 |  |  | 313.0 |  |
Total Other Liabilities(1) | 5,155.6 |  |  | 4,931.9 |  |
Commitments and Contingencies (Refer to Note 14, "Other Commitments and Contingencies") |  |  |  |
Total Capitalization and Liabilities | $ | 34,402.9 |  |  | $ | 31,788.1 |  |

(1)Includes $54.4 million and $53.7 million at September 30, 2025 and December 31, 2024, respectively, of current liabilities and $55.0 million and $58.3 million at September 30, 2025 and December 31, 2024, respectively, of other liabilities, and finance leases of $40.2 million and $40.4 million at September 30, 2025 and December 31, 2024 respectively, of consolidated VIEs that creditors do not have recourse to our general credit. Refer to Note 4, "Noncontrolling Interests," for additional information.
The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
12

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Condensed Statements of Consolidated Cash Flows (unaudited)

Nine Months Ended September 30, (in millions) | 2025 |  | 2024
Operating Activities |  |  |
Net Income | $ | 734.2 |  |  | $ | 600.4 |
Adjustments to Reconcile Net Income to Net Cash from Operating Activities: |  |  |
Depreciation and amortization | 852.2 |  |  | 765.1 |
Deferred income taxes and investment tax credits | 153.5 |  |  | 109.1 |
Loss on sale of assets | 0.2 |  |  | 1.1 |
Payments for asset retirement obligations | (50.0) |  |  | (55.0) |
Other adjustments | 22.5 |  |  | (14.9) |
Changes in Assets and Liabilities: |  |  |
Components of working capital(1) | (26.0) |  |  | (85.8) |
Regulatory assets/liabilities | (19.5) |  |  | (35.6) |
Deferred charges and other noncurrent assets | (24.4) |  |  | (45.1) |
Other noncurrent liabilities and deferred credits | 7.0 |  |  | 2.4 |
Net Cash Flows from Operating Activities | 1,649.7 |  |  | 1,241.7 |
Investing Activities |  |  |
Capital expenditures | (1,936.0) |  |  | (1,854.0) |
Cost of removal | (113.8) |  |  | (108.9) |
Milestone payments to renewable generation asset developers | (1,091.7) |  |  | (478.8) |
Advanced deposits | (161.3) |  |  | — |
Other investing activities | (93.8) |  |  | 27.2 |
Net Cash Flows used for Investing Activities | (3,396.6) |  |  | (2,414.5) |
Financing Activities |  |  |
Proceeds from issuance of long-term debt | 2,362.0 |  |  | 2,229.6 |
Repayments of finance lease obligations | (17.3) |  |  | (20.4) |
Repayments of long-term debt | (1,250.0) |  |  | — |
Repayment of short-term debt (maturity > 90 days) | — |  |  | (1,650.0) |
Net change in commercial paper and other short-term borrowings | 655.4 |  |  | (1,141.6) |
Issuance of common stock, net of issuance costs | 259.1 |  |  | 507.9 |
Redemption of preferred stock | — |  |  | (486.1) |
Preferred stock redemption premium | — |  |  | (14.0) |
Equity costs, premiums and other debt related costs | (22.0) |  |  | (62.9) |
Contributions from NIPSCO minority interest holders | 145.3 |  |  | 99.5 |
Distribution to NIPSCO minority interest holders | (55.5) |  |  | (32.0) |
Distributions to tax equity partners | (12.8) |  |  | (14.3) |
Dividends paid - common stock | (396.4) |  |  | (357.0) |
Dividends paid - preferred stock | — |  |  | (8.2) |
Net Cash Flows from (used for) Financing Activities | 1,667.8 |  |  | (949.5) |
Change in cash, cash equivalents and restricted cash | (79.1) |  |  | (2,122.3) |
Cash, cash equivalents and restricted cash at beginning of period | 198.6 |  |  | 2,281.1 |
Cash, Cash Equivalents and Restricted Cash at End of Period | $ | 119.5 |  |  | $ | 158.8 |
(1) Refer to Note 18, "Supplemental Disclosures of Cash Flow Information," for additional information.

Reconciliation to Balance Sheet

Nine Months Ended September 30, (in millions) | 2025
Cash and cash equivalents | 95.0
Restricted cash | 24.5
Total Cash, Cash Equivalents and Restricted Cash | 119.5

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
13

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Condensed Statements of Consolidated Equity (unaudited)

(in millions) | Common Stock |  | Preferred Stock |  | Treasury Stock |  | Additional Paid-In Capital |  | Retained Deficit |  | Accumulated Other Comprehensive Loss |  | Noncontrolling Interest in Consolidated Subsidiaries |  | Total
Balance as of June 30, 2025 | $ | 4.7 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,538.0 |  |  | $ | (532.1) |  |  | $ | (28.2) |  |  | $ | 2,114.4 |  |  | $ | 10,996.9 |
Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | — |  |  | — |  |  | — |  |  | — |  |  | 94.7 |  |  | — |  |  | 12.3 |  |  | 107.0 |
Other comprehensive income, net of tax | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 15.2 |  |  | — |  |  | 15.2 |
Dividends: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock ($0.280 per share) | — |  |  | — |  |  | — |  |  | — |  |  | (134.6) |  |  | — |  |  | — |  |  | (134.6) |
Noncontrolling Interests: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 11.0 |  |  | 11.0 |
Distributions to noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (14.1) |  |  | (14.1) |
Stock issuances: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | — |  |  | — |  |  | 1.9 |  |  | — |  |  | — |  |  | — |  |  | 1.9 |
Long-term incentive plan | — |  |  | — |  |  | — |  |  | 7.2 |  |  | — |  |  | — |  |  | — |  |  | 7.2 |
401(k) and profit sharing | — |  |  | — |  |  | — |  |  | 2.4 |  |  | — |  |  | — |  |  | — |  |  | 2.4 |
ATM program | 0.1 |  |  | — |  |  | — |  |  | 248.8 |  |  | — |  |  | — |  |  | — |  |  | 248.9 |
Balance as of September 30, 2025 | $ | 4.8 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,798.3 |  |  | $ | (572.0) |  |  | $ | (13.0) |  |  | $ | 2,123.6 |  |  | $ | 11,241.8 |
(in millions) | Common Stock |  | Preferred Stock |  | Treasury Stock |  | Additional Paid-In Capital |  | Retained Deficit |  | Accumulated Other Comprehensive Loss |  | Noncontrolling Interest in Consolidated Subsidiaries |  | Total
Balance as of December 31, 2024 | $ | 4.7 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,521.5 |  |  | $ | (711.7) |  |  | $ | (30.4) |  |  | $ | 1,984.1 |  |  | $ | 10,668.3 |
Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | — |  |  | — |  |  | — |  |  | — |  |  | 671.7 |  |  | — |  |  | 62.5 |  |  | 734.2 |
Other comprehensive income, net of tax | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 17.4 |  |  | — |  |  | 17.4 |
Dividends: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock ($1.120 per share) | — |  |  | — |  |  | — |  |  | — |  |  | (532.0) |  |  | — |  |  | — |  |  | (532.0) |
Noncontrolling Interests: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 145.3 |  |  | 145.3 |
Distributions to noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (68.3) |  |  | (68.3) |
Stock issuances: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | — |  |  | — |  |  | 5.5 |  |  | — |  |  | — |  |  | — |  |  | 5.5 |
Long-term incentive plan | — |  |  | — |  |  | — |  |  | 15.3 |  |  | — |  |  | — |  |  | — |  |  | 15.3 |
401(k) and profit sharing | — |  |  | — |  |  | — |  |  | 7.2 |  |  | — |  |  | — |  |  | — |  |  | 7.2 |
ATM program | 0.1 |  |  | — |  |  | — |  |  | 248.8 |  |  | — |  |  | — |  |  | — |  |  | 248.9 |
Balance as of September 30, 2025 | $ | 4.8 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,798.3 |  |  | $ | (572.0) |  |  | $ | (13.0) |  |  | $ | 2,123.6 |  |  | $ | 11,241.8 |

14

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ITEM 1. FINANCIAL STATEMENTS (continued)

(in millions) | Common Stock |  | Preferred Stock |  | Treasury Stock |  | Additional Paid-In Capital |  | Retained Deficit |  | Accumulated Other Comprehensive Loss |  | Noncontrolling Interest in Consolidated Subsidiaries |  | Total
Balance as of June 30, 2024 | $ | 4.5 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 8,894.2 |  |  | $ | (896.2) |  |  | $ | (33.6) |  |  | $ | 1,950.6 |  |  | $ | 9,819.6 |
Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | — |  |  | — |  |  | — |  |  | — |  |  | 85.7 |  |  | — |  |  | 11.3 |  |  | 97.0 |
Other comprehensive income, net of tax | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4.0 |  |  | — |  |  | 4.0 |
Dividends: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock ($0.265 per share) | — |  |  | — |  |  | — |  |  | — |  |  | (124.4) |  |  | — |  |  | — |  |  | (124.4) |
Noncontrolling Interests: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 39.8 |  |  | 39.8 |
Distributions to noncontrolling interest | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (17.9) |  |  | (17.9) |
Stock issuances: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | — |  |  | — |  |  | 1.7 |  |  | — |  |  | — |  |  | — |  |  | 1.7 |
Long-term incentive plan | — |  |  | — |  |  | — |  |  | 8.0 |  |  | — |  |  | — |  |  | — |  |  | 8.0 |
401(k) and profit sharing | — |  |  | — |  |  | — |  |  | 2.2 |  |  | — |  |  | — |  |  | — |  |  | 2.2 |
ATM program | 0.2 |  |  | — |  |  | — |  |  | 498.6 |  |  | — |  |  | — |  |  | — |  |  | 498.8 |
Balance as of September 30, 2024 | $ | 4.7 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,404.7 |  |  | $ | (934.9) |  |  | $ | (29.6) |  |  | $ | 1,983.8 |  |  | $ | 10,328.8 |
(in millions) | Common Stock |  | Preferred Stock |  | Treasury Stock |  | Additional Paid-In Capital |  | Retained Deficit |  | Accumulated Other Comprehensive Loss |  | Noncontrolling Interest in Consolidated Subsidiaries |  | Total
Balance as of December 31, 2023 | $ | 4.5 |  |  | $ | 486.1 |  |  | $ | (99.9) |  |  | $ | 8,879.5 |  |  | $ | (967.0) |  |  | $ | (33.6) |  |  | $ | 1,866.7 |  |  | $ | 10,136.3 |
Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | — |  |  | — |  |  | — |  |  | — |  |  | 536.5 |  |  | — |  |  | 63.9 |  |  | 600.4 |
Other comprehensive income, net of tax | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4.0 |  |  | — |  |  | 4.0 |
Dividends: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock ($1.060 per share) | — |  |  | — |  |  | — |  |  | — |  |  | (482.3) |  |  | — |  |  | — |  |  | (482.3) |
Preferred stock (See Note 6) | — |  |  | — |  |  | — |  |  | — |  |  | (8.1) |  |  | — |  |  | — |  |  | (8.1) |
Noncontrolling Interests: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 99.5 |  |  | 99.5 |
Distributions to noncontrolling interest | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (46.3) |  |  | (46.3) |
Stock issuances (redemptions): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Series B and B-1 Preferred stock redemption | — |  |  | (486.1) |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (486.1) |
Series B and B-1 Preferred stock redemption premium | — |  |  | — |  |  | — |  |  | — |  |  | (14.0) |  |  | — |  |  | — |  |  | (14.0) |
Employee stock purchase plan | — |  |  | — |  |  | — |  |  | 4.7 |  |  | — |  |  | — |  |  | — |  |  | 4.7 |
Long-term incentive plan | — |  |  | — |  |  | — |  |  | 14.9 |  |  | — |  |  | — |  |  | — |  |  | 14.9 |
401(k) and profit sharing | — |  |  | — |  |  | — |  |  | 7.0 |  |  | — |  |  | — |  |  | — |  |  | 7.0 |
ATM program | 0.2 |  |  | — |  |  | — |  |  | 498.6 |  |  | — |  |  | — |  |  | — |  |  | 498.8 |
Balance as of September 30, 2024 | $ | 4.7 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,404.7 |  |  | $ | (934.9) |  |  | $ | (29.6) |  |  | $ | 1,983.8 |  |  | $ | 10,328.8 |

15

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Condensed Statements of Consolidated Equity (unaudited) (continued)

| Preferred |  | Common
Shares (in thousands) | Shares |  | Shares |  | Treasury |  | Outstanding
Balance as of June 30, 2025 | — |  |  | 474,747 |  |  | (3,963) |  |  | 470,784 |
Issued: |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | 47 |  |  | — |  |  | 47 |
Long-term incentive plan | — |  |  | 24 |  |  | — |  |  | 24 |
401(k) and profit sharing | — |  |  | 55 |  |  | — |  |  | 55 |
ATM program | — |  |  | 6,226 |  |  | — |  |  | 6,226 |
Balance as of September 30, 2025 | — |  |  | 481,099 |  |  | (3,963) |  |  | 477,136 |
| Preferred |  | Common
Shares (in thousands) | Shares |  | Shares |  | Treasury |  | Outstanding
Balance as of December 31, 2024 | — |  |  | 473,785 |  |  | (3,963) |  |  | 469,822 |
Issued: |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | 141 |  |  | — |  |  | 141 |
Long-term incentive plan | — |  |  | 768 |  |  | — |  |  | 768 |
401(k) and profit sharing | — |  |  | 179 |  |  | — |  |  | 179 |
ATM program | — |  |  | 6,226 |  |  | — |  |  | 6,226 |
Balance as of September 30, 2025 | — |  |  | 481,099 |  |  | (3,963) |  |  | 477,136 |
| Preferred |  | Common
Shares (in thousands) | Shares |  | Shares |  | Treasury |  | Outstanding
Balance as of June 30, 2024 | — |  |  | 452,362 |  |  | (3,963) |  |  | 448,399 |
Issued: |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | 59 |  |  | — |  |  | 59 |
Long-term incentive plan | — |  |  | 32 |  |  | — |  |  | 32 |
401(k) and profit sharing | — |  |  | 69 |  |  | — |  |  | 69 |
ATM program | — |  |  | 18,148 |  |  | — |  |  | 18,148 |
Balance as of September 30, 2024 | — |  |  | 470,670 |  |  | (3,963) |  |  | 466,707 |
| Preferred |  | Common
Shares (in thousands) | Shares |  | Shares |  | Treasury |  | Outstanding
Balance as of December 31, 2023 | 40 |  |  | 451,345 |  |  | (3,963) |  |  | 447,382 |
Issued: |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | 170 |  |  | — |  |  | 170 |
Long-term incentive plan | — |  |  | 761 |  |  | — |  |  | 761 |
401(k) and profit sharing | — |  |  | 246 |  |  | — |  |  | 246 |
ATM program | — |  |  | 18,148 |  |  | — |  |  | 18,148 |
Redeemed: |  |  |  |  |  |  |
Series B and B-1 Preferred Stock | (40) |  |  | — |  |  | — |  |  | — |
Balance as of September 30, 2024 | — |  |  | 470,670 |  |  | (3,963) |  |  | 466,707 |

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
16

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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
1. Basis of Accounting Presentation
Our accompanying Condensed Consolidated Financial Statements (unaudited) reflect all normal recurring adjustments that are necessary, in the opinion of management, to present fairly the results of operations in accordance with GAAP in the United States of America. The accompanying financial statements include the accounts of us, our majority-owned subsidiaries, and VIEs of which we are the primary beneficiary after the elimination of all intercompany accounts and transactions.
The accompanying financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024. Income for interim periods may not be indicative of results for the calendar year due to weather variations and other factors.
The Condensed Consolidated Financial Statements (unaudited) have been prepared pursuant to the rules and regulations of the SEC. Certain information and note disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations, although we believe that the disclosures made in this Quarterly Report on Form 10-Q are adequate to make the information herein not misleading.
2. Recent Accounting Pronouncements
Recently Issued Accounting Pronouncements
In September 2025, the FASB issued ASU 2025-06, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. This pronouncement updates the guidance on capitalization of internal-use software, including removing the development stages utilized for evaluation of when certain activities are capital eligible. The ASU instead provides that an entity is required to start capitalizing eligible software development costs when (1) management has authorized and committed to funding the software project and (2) it is probable that the project will be completed and the software will be used to perform the function intended, which is referred to as the “probable-to-complete recognition threshold”. This probable-to-complete threshold includes an evaluation of whether there is significant uncertainty associated with the development activities of the software. The ASU is effective for fiscal years beginning after December 15, 2027. We are currently evaluating the impacts this amendment will have on our internal-use software capitalization policy.
In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40). This pronouncement requires disaggregated disclosure of income statement expenses for public business entities. The ASU requires disclosure in tabular format of disaggregation of relevant expense captions presented on the income statement by certain natural expense categories with certain related qualitative disclosures within the notes to the financial statements. The ASU does not change the expense captions an entity presents on the income statement. The ASU is effective for fiscal years beginning after December 15, 2026, and interim reporting periods within annual reporting periods beginning after December 15, 2027, as defined in ASU 2025-01, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40). We are currently evaluating the impacts this amendment will have on our required disclosures.
In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This pronouncement enhances required income tax disclosures. The pronouncement will require disclosure of specific categories and reconciling items included in the rate reconciliation, disaggregation between federal, state and local income taxes paid, and disclosure of income taxes paid by jurisdictions over a certain threshold. Additionally, the pronouncement eliminates certain required disclosures related to unrecognized tax benefits. This ASU is effective for annual periods beginning after December 15, 2024, with early adoption permitted, and is to be applied on a prospective basis with retrospective application permitted. We will implement and provide the required disclosures in our Annual Report on Form 10-K for the year ended December 31, 2025.
Recently Adopted Accounting Pronouncements
In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This pronouncement enhances annual and interim disclosure requirements over reportable segments, primarily through enhanced disclosures about significant segment expenses. Specifically, the pronouncement requires disclosure of significant segment expenses that are regularly provided to the CODM and included within each reported measure of segment profit or loss, disclosure of an amount for other segment items representing the difference between segment revenue and segment expenses already disclosed, disclosure of all required annual disclosures for interim periods and disclosure of title and
17

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
position of the CODM and how the CODM uses reported measures. The pronouncement also allows for more than one measure of segment profit if the CODM uses more than one measure in assessing segment performance. This pronouncement was effective for annual periods beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. NiSource adopted this pronouncement as of December 31, 2024, with retrospective application and updated its disclosures to include significant expenses regularly provided to the CODM, the CODM's title and how the CODM utilizes reported measures. See Note 16, "Business Segment Information," for further discussion.
3. Revenue Recognition
Revenue Disaggregation and Reconciliation. We disaggregate revenue from contracts with customers based upon reportable segment, as well as by customer class. The Columbia Operations segment provides regulated natural gas service and transportation for residential, commercial and industrial customers in Ohio, Pennsylvania, Virginia, Kentucky, and Maryland. The NIPSCO Operations segment provides regulated gas and electric service in the northern part of Indiana.
The tables below reconcile revenue disaggregation by customer class to segment revenue, as well as to revenues reflected on the Condensed Statements of Consolidated Income (unaudited):
18

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Three months ended September 30, 2025 (in millions) | Columbia Operations |  | NIPSCO Operations |  | Corporate and Other |  | Total
Gas Distribution |  |  |  |  |  |  |
Residential | $ | 328.1 |  |  | $ | 72.9 |  |  | $ | — |  |  | $ | 401.0 |
Commercial | 95.1 |  |  | 32.2 |  |  | — |  |  | 127.3 |
Industrial | 36.0 |  |  | 19.7 |  |  | — |  |  | 55.7 |
Off-system | 13.8 |  |  | — |  |  | — |  |  | 13.8 |
Miscellaneous(1) | 6.7 |  |  | 2.6 |  |  | — |  |  | 9.3 |
Subtotal | $ | 479.7 |  |  | $ | 127.4 |  |  | $ | — |  |  | $ | 607.1 |
Electric Generation and Power Delivery |  |  |  |  |  |  |
Residential | $ | — |  |  | $ | 254.6 |  |  | $ | — |  |  | $ | 254.6 |
Commercial | — |  |  | 210.6 |  |  | — |  |  | 210.6 |
Industrial | — |  |  | 156.2 |  |  | — |  |  | 156.2 |
Wholesale | — |  |  | 18.4 |  |  | — |  |  | 18.4 |
Miscellaneous(1) | — |  |  | (6.7) |  |  | — |  |  | (6.7) |
Subtotal | $ | — |  |  | $ | 633.1 |  |  | $ | — |  |  | $ | 633.1 |
Total Customer Revenues(2) | 479.7 |  |  | 760.5 |  |  | — |  |  | 1,240.2 |
Other Revenues(3) | 5.2 |  |  | 26.5 |  |  | 1.2 |  |  | 32.9 |
Total Operating Revenues | $ | 484.9 |  |  | $ | 787.0 |  |  | $ | 1.2 |  |  | $ | 1,273.1 |
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations primarily relate to late fees and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets. Amounts included in Corporate and Other primarily relate to products and services revenue.
Three months ended September 30, 2024 (in millions) | Columbia Operations |  | NIPSCO Operations |  | Corporate and Other |  | Total
Gas Distribution |  |  |  |  |  |  |
Residential | $ | 296.9 |  |  | $ | 66.8 |  |  | $ | — |  |  | $ | 363.7 |
Commercial | 78.3 |  |  | 28.6 |  |  | — |  |  | 106.9 |
Industrial | 32.0 |  |  | 16.4 |  |  | — |  |  | 48.4 |
Off-system | 7.1 |  |  | — |  |  | — |  |  | 7.1 |
Wholesale | 0.1 |  |  | — |  |  | — |  |  | 0.1 |
Miscellaneous(1) | 2.9 |  |  | 1.9 |  |  | — |  |  | 4.8 |
Subtotal | $ | 417.3 |  |  | $ | 113.7 |  |  | $ | — |  |  | $ | 531.0 |
Electric Generation and Power Delivery |  |  |  |  |  |  |
Residential | $ | — |  |  | $ | 197.9 |  |  | $ | — |  |  | $ | 197.9 |
Commercial | — |  |  | 172.7 |  |  | — |  |  | 172.7 |
Industrial | — |  |  | 124.8 |  |  | — |  |  | 124.8 |
Wholesale | — |  |  | 15.0 |  |  | — |  |  | 15.0 |
Public Authority | — |  |  | 2.0 |  |  | — |  |  | 2.0 |
Miscellaneous(1) | — |  |  | 2.7 |  |  | — |  |  | 2.7 |
Subtotal | $ | — |  |  | $ | 515.1 |  |  | $ | — |  |  | $ | 515.1 |
Total Customer Revenues(2) | 417.3 |  |  | 628.8 |  |  | — |  |  | 1,046.1 |
Other Revenues(3) | 6.1 |  |  | 23.8 |  |  | 0.3 |  |  | 30.2 |
Total Operating Revenues | $ | 423.4 |  |  | $ | 652.6 |  |  | $ | 0.3 |  |  | $ | 1,076.3 |
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations, primarily relate to revenue refunds, public repairs and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets.

19

Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Nine months ended September 30, 2025 (in millions) | Columbia Operations |  | NIPSCO Operations |  | Corporate and Other |  | Total
Gas Distribution |  |  |  |  |  |  |
Residential | $ | 1,576.3 |  |  | $ | 478.5 |  |  | $ | — |  |  | $ | 2,054.8 |
Commercial | 527.8 |  |  | 180.8 |  |  | — |  |  | $ | 708.6 |
Industrial | 121.5 |  |  | 73.7 |  |  | — |  |  | $ | 195.2 |
Off-system | 58.9 |  |  | — |  |  | — |  |  | $ | 58.9 |
Miscellaneous(1) | 27.4 |  |  | 10.6 |  |  | — |  |  | $ | 38.0 |
Subtotal | $ | 2,311.9 |  |  | $ | 743.6 |  |  | $ | — |  |  | $ | 3,055.5 |
Electric Generation and Power Delivery |  |  |  |  |  |  |
Residential | $ | — |  |  | $ | 586.4 |  |  | $ | — |  |  | $ | 586.4 |
Commercial | — |  |  | 531.7 |  |  | — |  |  | $ | 531.7 |
Industrial | — |  |  | 432.3 |  |  | — |  |  | $ | 432.3 |
Wholesale | — |  |  | 37.9 |  |  | — |  |  | $ | 37.9 |
Miscellaneous(1) | — |  |  | (7.6) |  |  | — |  |  | $ | (7.6) |
Subtotal | $ | — |  |  | $ | 1,580.7 |  |  | $ | — |  |  | $ | 1,580.7 |
Total Customer Revenues(2) | 2,311.9 |  |  | 2,324.3 |  |  | — |  |  | 4,636.2 |
Other Revenues(3) | 14.8 |  |  | 84.7 |  |  | 3.6 |  |  | 103.1 |
Total Operating Revenues | $ | 2,326.7 |  |  | $ | 2,409.0 |  |  | $ | 3.6 |  |  | $ | 4,739.3 |
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations primarily relate to late fees and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets. Amounts included in Corporate and Other primarily relate to products and services revenue.
Nine months ended September 30, 2024 (in millions) | Columbia Operations |  | NIPSCO Operations |  | Corporate and Other |  | Total
Gas Distribution |  |  |  |  |  |  |
Residential | $ | 1,257.2 |  |  | $ | 357.5 |  |  | $ | — |  |  | $ | 1,614.7 |
Commercial | 395.6 |  |  | 134.0 |  |  | — |  |  | $ | 529.6 |
Industrial | 105.1 |  |  | 56.3 |  |  | — |  |  | $ | 161.4 |
Off-system | 30.5 |  |  | — |  |  | — |  |  | $ | 30.5 |
Wholesale | 1.1 |  |  | — |  |  | — |  |  | $ | 1.1 |
Miscellaneous(1) | 15.4 |  |  | 12.5 |  |  | — |  |  | $ | 27.9 |
Subtotal | $ | 1,804.9 |  |  | $ | 560.3 |  |  | $ | — |  |  | $ | 2,365.2 |
Electric Generation and Power Delivery |  |  |  |  |  |  |
Residential | $ | — |  |  | $ | 498.6 |  |  | $ | — |  |  | $ | 498.6 |
Commercial | — |  |  | 470.0 |  |  | — |  |  | $ | 470.0 |
Industrial | — |  |  | 360.4 |  |  | — |  |  | $ | 360.4 |
Wholesale | — |  |  | 32.4 |  |  | — |  |  | $ | 32.4 |
Public Authority | — |  |  | 6.0 |  |  | — |  |  | $ | 6.0 |
Miscellaneous(1) | — |  |  | 10.6 |  |  | — |  |  | $ | 10.6 |
Subtotal | $ | — |  |  | $ | 1,378.0 |  |  | $ | — |  |  | $ | 1,378.0 |
Total Customer Revenues(2) | 1,804.9 |  |  | 1,938.3 |  |  | — |  |  | 3,743.2 |
Other Revenues(3) | 59.6 |  |  | 63.9 |  |  | 0.6 |  |  | 124.1 |
Total Operating Revenues | $ | 1,864.5 |  |  | $ | 2,002.2 |  |  | $ | 0.6 |  |  | $ | 3,867.3 |
(1)Amounts included in Columbia Operations primarily relate to earnings share mechanisms and late fees. Amounts included in NIPSCO Operations, primarily relate to revenue refunds, public repairs and property rentals. (2)Customer revenue amounts exclude intersegment revenues. See Note 16, "Business Segment Information," for discussion of intersegment revenues. (3)Amounts included in Columbia Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms. Amounts included in NIPSCO Operations primarily relate to alternative revenue programs including weather normalization adjustment mechanisms, MISO multi-value projects and revenue from non-jurisdictional transmission assets.

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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
Customer Accounts Receivable. Accounts receivable on our Condensed Consolidated Balance Sheets (unaudited) includes both billed and unbilled amounts, as well as certain amounts that are not related to customer revenues. Unbilled amounts of accounts receivable relate to a portion of a customer’s consumption of gas or electricity from the date of the last cycle billing through the last day of the month (balance sheet date). Factors taken into consideration when estimating unbilled revenue include historical usage, customer rates, and weather. A significant portion of our operations are subject to seasonal fluctuations in sales. During the heating season, primarily from November through March, revenues and receivables from gas sales are more significant than in other months. The balances of customer receivables as of September 30, 2025 and December 31, 2024 are presented in the table below. We had no significant contract assets or liabilities during the period. Additionally, we have not incurred any significant costs to obtain or fulfill contracts.

(in millions) | Customer Accounts Receivable, Billed (less reserve) |  | Customer Accounts Receivable, Unbilled (less reserve) |  |
Balance as of December 31, 2024 | $ | 525.1 |  |  | $ | 408.1 |  |  |
Balance as of September 30, 2025 | $ | 444.6 |  |  | $ | 219.5 |  |  |

Utility revenues are billed to customers monthly on a cycle basis. We expect that substantially all customer accounts receivable will be collected following customer billing, as this revenue consists primarily of periodic, tariff-based billings for service and usage. We maintain common utility credit risk mitigation practices, including requiring deposits and actively pursuing collection of past due amounts. Our regulated operations also utilize certain regulatory mechanisms that facilitate recovery of bad debt costs within tariff-based rates, which provides further evidence of collectibility. It is probable that substantially all of the consideration to which we are entitled from customers will be collected upon satisfaction of performance obligations.
Allowance for Credit Losses. To evaluate for expected credit losses, customer account receivables are pooled based on similar risk characteristics, such as customer type, geography, payment terms, and related macro-economic risks. Expected credit losses are established using a model that considers historical collections experience, current information, and reasonable and supportable forecasts. Internal and external inputs are used in our credit model including, but not limited to, energy consumption trends, revenue projections, actual charge-offs data, recoveries data, shut-offs, customer delinquencies, final bill data, and inflation. We continuously evaluate available information relevant to assessing collectability of current and future receivables. We evaluate creditworthiness of specific customers periodically or following changes in facts and circumstances. When we become aware of a specific commercial or industrial customer's inability to pay, an allowance for expected credit losses is recorded for the relevant amount. We also monitor other circumstances that could affect our overall expected credit losses including, but not limited to, creditworthiness of overall population in service territories, adverse conditions impacting an industry sector, and current economic conditions.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
At each reporting period, we record expected credit losses to an allowance for credit losses account. When deemed to be uncollectible, customer accounts are written-off. A rollforward of our allowance for credit losses as of September 30, 2025 and December 31, 2024 are presented in the table below:

(in millions) | Columbia Operations |  | NIPSCO Operations |  |  |  | Corporate and Other |  | Total
Balance as of December 31, 2024 | $ | 9.8 |  |  | $ | 13.9 |  |  |  |  | $ | — |  |  | $ | 23.7 |
Current period provisions | 26.2 |  |  | 10.2 |  |  |  |  | — |  |  | 36.4 |
Write-offs charged against allowance | (39.7) |  |  | (9.2) |  |  |  |  | — |  |  | (48.9) |
Recoveries of amounts previously written off | 6.7 |  |  | 0.7 |  |  |  |  | — |  |  | 7.4 |
Balance as of September 30, 2025 | $ | 3.0 |  |  | $ | 15.6 |  |  |  |  | $ | — |  |  | $ | 18.6 |

(in millions) | Columbia Operations |  | NIPSCO Operations |  |  |  | Corporate and Other |  | Total
Balance as of December 31, 2023 | $ | 10.2 |  |  | $ | 11.9 |  |  |  |  | $ | 0.8 |  |  | $ | 22.9 |
Current period provisions | 26.7 |  |  | 12.1 |  |  |  |  | — |  |  | 38.8 |
Write-offs charged against allowance | (43.9) |  |  | (11.0) |  |  |  |  | (0.8) |  |  | (55.7) |
Recoveries of amounts previously written off | 16.8 |  |  | 0.9 |  |  |  |  | — |  |  | 17.7 |
Balance as of December 31, 2024 | $ | 9.8 |  |  | $ | 13.9 |  |  |  |  | $ | — |  |  | $ | 23.7 |

4. Noncontrolling Interests
Variable Interest Entities. A VIE is an entity in which the controlling interest is determined through means other than a majority voting interest. NIPSCO is the managing member and operator of two wind JVs, Rosewater and Indiana Crossroads Wind, which have 102 MW and 302 MW of nameplate capacity, respectively. NIPSCO is also the managing member and operator of two solar JVs, Indiana Crossroads Solar and Dunns Bridge I, which have a nameplate capacity of 200 MW and 265 MW, respectively. We have determined that these JVs are VIEs. NIPSCO controls decisions that are significant to these entities' ongoing operations and economic results. Therefore, we have concluded that NIPSCO is the primary beneficiary and have consolidated all four entities.
Members of each respective JV include NIPSCO (who is the managing member) and a tax equity partner. Earnings, tax attributes and cash flows are allocated to both NIPSCO and the tax equity partner in varying percentages by category and over the life of the partnership. NIPSCO and each tax equity partner contributed cash to the respective JV. Once the tax equity partner has earned their negotiated rate of return and have reached a stated contractual date, NIPSCO has the option to purchase the remaining interest in the respective JV, at fair market value, from the tax equity partner. NIPSCO has an obligation to purchase 100% of the electricity generated by each commercially operational JV.
We did not provide any financial or other support during the quarter that was not contractually required.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
Our Condensed Consolidated Balance Sheets (unaudited) included the following assets and liabilities associated with VIEs.

(in millions) | September 30, 2025 |  | December 31, 2024
Net property, plant and equipment | $ | 1,284.4 |  |  | $ | 1,323.8 |
Current assets | 59.6 |  |  | 65.0 |
Total assets(1) | 1,344.0 |  |  | 1,388.8 |
Current liabilities | 54.4 |  |  | 53.7 |
Asset retirement obligations | 55.0 |  |  | 58.3 |
Finance lease obligations | 40.2 |  |  | 40.4 |
Total liabilities(1)(2) | $ | 149.6 |  |  | $ | 152.4 |

(1)The assets of each consolidated VIE can only be used to settle obligations of the respective consolidated VIE. The creditors of the liabilities of the VIEs do not have recourse to the general credit of the primary beneficiary.
(2)In addition to the amounts disclosed above there is a de minimis amount of other noncurrent assets and liabilities at Rosewater as of September 30, 2025.
Voting Interest Entities. We retain a controlling financial interest in NIPSCO Holdings II and its subsidiaries and consolidate their financial results. The following table provides information about the contributions from and distributions to our NIPSCO minority interest holders included in our Condensed Statements of Consolidated Cash Flows (unaudited) and Condensed Statements of Consolidated Equity (unaudited).

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | 2025 |  | 2024
Contributions from NIPSCO minority interest holders | $ | 11.0 |  |  | $ | 39.8 |  |  | $ | 145.3 |  |  | $ | 99.5 |
Distributions to NIPSCO minority interest holders | 11.1 |  |  | 11.8 |  |  | 55.5 |  |  | 32.0 |

5. Earnings Per Share
The calculations of basic and diluted EPS are based on the weighted average number of shares of common stock and potential common stock outstanding during the period. Diluted EPS includes the incremental effects of the various long-term incentive compensation plans and ATM forward sale agreements under the treasury stock method when the impact would be dilutive (See Note 6, "Equity").
We use the two-class method of computing earnings per share because we have participating securities in the form of non-vested restricted stock units with a non-forfeitable right to dividend equivalents, for which vesting is predicated solely on the passage of time. The calculation of earnings per share using the two-class method excludes income attributable to these participating securities from the numerator and excludes the dilutive impact of those shares from the denominator.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
The following table presents the calculation of our basic and diluted EPS:

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions, except per share amounts) | 2025 |  | 2024 |  | 2025 |  | 2024
Numerator: |  |  |  |  |  |  |
Net Income Available to Common Shareholders | $ | 94.7 |  |  | $ | 85.7 |  |  | $ | 671.7 |  |  | $ | 515.8 |
Less: Income allocated to participating securities | 0.3 |  |  | 0.2 |  |  | 1.4 |  |  | 0.9 |
Net Income Available to Common Shareholders - Basic | 94.4 |  |  | 85.5 |  |  | 670.3 |  |  | 514.9 |
Net Income Available to Common Shareholders - Diluted | $ | 94.4 |  |  | $ | 85.5 |  |  | $ | 670.3 |  |  | $ | 514.9 |
Denominator: |  |  |  |  |  |  |
Average common shares outstanding - Basic | 472.1 |  |  | 451.9 |  |  | 471.1 |  |  | 449.4 |
Dilutive potential common shares: |  |  |  |  |  |  |
Shares contingently issuable under employee stock plans | 1.0 |  |  | 0.9 |  |  | 1.1 |  |  | 0.9 |
Shares restricted under employee stock plans | 0.4 |  |  | 0.3 |  |  | 0.5 |  |  | 0.3 |
ATM forward sale agreements | 0.2 |  |  | 1.4 |  |  | 0.1 |  |  | 0.8 |
Average Common Shares - Diluted | 473.7 |  |  | 454.5 |  |  | 472.8 |  |  | 451.4 |
Earnings per common share: |  |  |  |  |  |  |
Basic | $ | 0.20 |  |  | $ | 0.19 |  |  | 1.42 |  | 1.15
Diluted | $ | 0.20 |  |  | $ | 0.19 |  |  | 1.42 |  | 1.14

6. Equity
ATM Program. In February 2024, we entered into eight separate equity distribution agreements pursuant to which we are able to sell up to an aggregate of $900.0 million of our common stock.
In February 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,000,000 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $40.10 per share. In September 2025, we settled the forward sale agreement in shares for $80.0 million, based on a net price of $40.02 per share.
In March 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 1,707,320 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $41.00 per share. In September 2025, we settled the forward sale agreement in shares for $69.9 million, based on a net price of $40.92 per share.
In June 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,518,393 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $39.71 per share. In September 2025, we settled the forward sale agreement in shares for $99.1 million, based on a net price of $39.36 per share.
As of September 30, 2025, the ATM program had approximately $47.5 million of capacity available. The program expires on December 31, 2025.
Series B and B-1 Preferred Stock. On March 15, 2024, we redeemed all 20,000 outstanding shares of Series B Preferred Stock for a redemption price of $25,000 per share and all 20,000 outstanding shares of Series B-1 Preferred Stock for a redemption price of $0.01 per share or $500.0 million in total.
There were no dividends declared per share for the Series B Preferred Stock during the three months ended September 30, 2025 and 2024. Dividends declared per share for the Series B Preferred Stock were zero and $406.25 during the nine months ended September 30, 2025 and 2024, respectively.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
7. Short-Term Borrowings
We generate short-term borrowings from our revolving credit facility, commercial paper program, and accounts receivable transfer programs. Each of these borrowing sources is described further below.
Revolving Credit Facility. We maintain a revolving credit facility to fund ongoing working capital requirements, including the provision of liquidity support for our commercial paper program, the issuance of letters of credit and general corporate purposes. Our revolving credit facility has a program limit of $1.85 billion and is comprised of a syndicate of banks. We had no outstanding borrowings under this facility as of September 30, 2025 and December 31, 2024.
Commercial Paper Program. Our commercial paper program has a program limit of $1.85 billion. We had $1,060.0 million and $604.6 million of commercial paper outstanding with weighted-average interest rates of 4.40% and 4.73% as of September 30, 2025 and December 31, 2024, respectively.
Accounts Receivable Transfer Programs. Columbia of Ohio, NIPSCO, and Columbia of Pennsylvania each maintain a receivables agreement whereby they transfer their customer accounts receivables to third-party financial institutions through consolidated special purpose entities. The three agreements expire between May 2026 and October 2026 and may be further extended if mutually agreed to by the parties thereto.
All receivables transferred to third parties are valued at face value, which approximates fair value due to their short-term nature. The amount of the undivided percentage ownership interest in the accounts receivables transferred is determined in part by required loss reserves under the agreements.
Transfers of accounts receivable are accounted for as secured borrowings resulting in the recognition of short-term borrowings on the Condensed Consolidated Balance Sheets (unaudited). As of September 30, 2025, the maximum amount of debt that could be borrowed related to our accounts receivable programs was $245.0 million.
We had $200.0 million and no short-term borrowings related to the securitization transactions as of September 30, 2025 and December 31, 2024, respectively.
For the nine months ended September 30, 2025 and 2024, $200.0 million and $(337.6) million, respectively, were recorded as cash flows from (used for) financing activities related to the change in short-term borrowings due to securitization transactions. Columbia of Ohio, NIPSCO and Columbia of Pennsylvania remain responsible for collecting on the receivables securitized, and the receivables cannot be transferred to another party.
Items listed above are presented net in the Condensed Statements of Consolidated Cash Flows (unaudited) as their maturities are less than 90 days.
8. Long-Term Debt
On March 27, 2025, we completed the issuance and sale of $750.0 million of 5.850% senior unsecured notes maturing in 2055, which resulted in approximately $739.6 million of net proceeds after discount and debt issuance costs.
On June 27, 2025, we completed the issuance and sale of an additional $750.0 million of 5.850% senior unsecured notes maturing in 2055 (the "2055 Notes"). The terms of the 2055 Notes, other than the issue date and the price to the public, are identical to the terms of, and constitute a reopening of, our 5.850% senior unsecured notes maturing in 2055 issued on March 27, 2025. With the incremental issuance, we now have $1.5 billion of 5.850% senior unsecured notes maturing in 2055. On June 27, 2025, we also completed the issuance and sale of $900.0 million of 5.350% senior unsecured notes maturing in 2035 (the "2035 Notes"). The issuances of the additional 2055 Notes and the 2035 Notes in June 2025 resulted in approximately $1.616 billion of total net proceeds after discount and debt issuance costs.
On August 15, 2025, we repaid $1,250.0 million of 0.95% senior unsecured notes at maturity.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
9. Regulatory Matters
Regulatory Assets and Liabilities. We follow the accounting and reporting requirements of ASC Topic 980, which provides that regulated entities account for and report assets and liabilities consistent with the economic effect of regulatory rate-making procedures when the rates established are designed to recover the costs of providing the regulated service and it is probable that such rates will be charged and collected from customers. Certain expenses and credits subject to utility regulation or rate determination normally reflected in income or expense are deferred on the balance sheet and are recognized in the income statement as the related amounts are included in customer rates and recovered from or refunded to customers. We assess the probability of collection for all of our regulatory assets each period. The offset to the regulatory liability associated with our renewable investments included in regulated rates is recorded in "Depreciation and amortization" on the Condensed Statements of Consolidated Income (unaudited).
Renewable generation filings. In February 2025, NIPSCO filed a petition with the IURC to modify its February 2023 order that approved a power purchase agreement related to Templeton and allow for NIPSCO to fully own Templeton. The IURC issued an order on September 24, 2025 approving the filed petition.
GenCo filing. In January 2025, GenCo, an indirect subsidiary of NiSource Inc., filed a declination of jurisdiction petition with the IURC related to the ownership, development, financing, construction and operation of generation facilities. This is an administrative filing and is a step in NIPSCO’s effort to set up a framework to accommodate megaload customers, including data centers. A settlement agreement among GenCo, NIPSCO, and a coalition of NIPSCO's largest industrial customers was approved by the IURC on September 24, 2025. In October 2025, the Indiana Office of the Utility Consumer Counselor ("OUCC") filed a limited Request for Rehearing with the IURC. Subsequently, the OUCC filed a Notice of Appeal of the IURC order approving the GenCo settlement, which was immediately stayed by the Court of Appeals to allow the IURC process to be completed.
NIPSCO Electric rate case filing. On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC. The IURC issued an order on June 26, 2025, approving the Settlement Agreement without modification. New rates were implemented in multiple steps beginning in July 2025 and will continue with the final step no later than March 2026.
10. Risk Management Activities
We are exposed to certain risks relating to our ongoing business operations; namely commodity price risk and interest rate risk. We recognize that the prudent and selective use of derivatives may help to limit volatility in the price of natural gas and manage interest rate exposure.
Risk management assets and liabilities on our derivatives are presented on the Condensed Consolidated Balance Sheets (unaudited) as shown below:

| September 30, 2025 |  | December 31, 2024
(in millions) | Assets |  | Liabilities |  | Assets |  | Liabilities
Current(1) |  |  |  |  |  |  |
Derivatives not designated as hedging instruments | $ | 10.5 |  |  | $ | 2.8 |  |  | $ | 9.1 |  |  | $ | 2.3 |
Total | $ | 10.5 |  |  | $ | 2.8 |  |  | $ | 9.1 |  |  | $ | 2.3 |
Noncurrent(2) |  |  |  |  |  |  |
Derivatives not designated as hedging instruments | $ | 12.8 |  |  | $ | 3.7 |  |  | $ | 17.9 |  |  | $ | 1.2 |
Total | $ | 12.8 |  |  | $ | 3.7 |  |  | $ | 17.9 |  |  | $ | 1.2 |

(1)Current assets and liabilities are presented in "Other current assets" and "Other accruals", respectively, on the Condensed Consolidated Balance Sheets (unaudited).
(2)Noncurrent assets and liabilities are presented in "Deferred charges and other" and "Other noncurrent liabilities and deferred credits", respectively, on the Condensed Consolidated Balance Sheets (unaudited).
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
Our derivative instruments are subject to enforceable master netting arrangements or similar agreements. No collateral was either received or posted related to our outstanding derivative positions at September 30, 2025. If the above gross asset and liability positions were presented net of amounts owed or receivable from counterparties, we would report a net asset position of $16.8 million and $23.5 million at September 30, 2025 and December 31, 2024, respectively.
Derivatives Not Designated as Hedging Instruments
Commodity price risk management. We, along with our utility customers, are exposed to variability in cash flows associated with natural gas purchases and volatility in natural gas prices. We purchase natural gas for sale and delivery to our retail, commercial and industrial customers, and for most customers the variability in the market price of gas is passed through in their rates. Some of our utility subsidiaries offer programs whereby variability in the market price of gas is assumed by the respective utility. The objective of our commodity price risk programs is to mitigate the gas cost variability on behalf of our customers associated with natural gas purchases or sales by economically hedging the various gas cost components using a combination of futures, options, forwards or other derivative contracts. At September 30, 2025 and December 31, 2024, we had 89.4 MMDth and 77.8 MMDth, respectively, of net energy derivative volumes outstanding related to our natural gas hedges.
NIPSCO has received approval for a program to lock in a fixed price for its natural gas customers using long-term forward purchase instruments and is limited to 20% of NIPSCO's average annual GCA purchase volume. As of September 30, 2025, the remaining terms of these instruments range from one to seven years. Likewise, Columbia of Pennsylvania has received approval for a 24-month rolling hedge program that will continue in perpetuity. The program is designed to financially hedge approximately 20% of the customers' annual demand. Under both programs all gains and losses on these derivative contracts are deferred as regulatory liabilities or assets and are remitted to or collected from customers through the relevant cost recovery mechanism.
The following table summarizes the gains and losses associated with the commodity price risk programs deferred as regulatory assets and liabilities:

(in millions) | September 30, 2025 |  | December 31, 2024
Regulatory Assets |  |  |
Losses on commodity price risk programs | $ | 10.9 |  |  | $ | 6.5 |
Regulatory Liabilities |  |  |
Gains on commodity price risk programs | 23.8 |  |  | 28.7 |

Our derivative instruments measured at fair value as of September 30, 2025 and December 31, 2024 do not contain any credit-risk-related contingent features.
Derivatives Designated as Hedging Instruments
Interest rate risk management. As of September 30, 2025 and December 31, 2024 we had no active interest rate swap positions. We have recorded the overall net loss related to previously settled interest rate swaps in AOCI. The gain or loss associated with each previously settled interest rate swap is amortized in interest expense over the term of each corresponding debt issuance. These amounts were immaterial for the three and nine months ended September 30, 2025 and 2024 and are recorded in "Interest expense, net" on the Condensed Statements of Consolidated Income (unaudited). Amounts expected to be reclassified to earnings during the next twelve months are immaterial. See Note 15, "Accumulated Other Comprehensive Loss," for additional information.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
11. Fair Value
A. Fair Value Measurements
Recurring Fair Value Measurements
The following tables present financial assets and liabilities measured and recorded at fair value on our Condensed Consolidated Balance Sheets (unaudited) on a recurring basis and their level within the fair value hierarchy as of September 30, 2025 and December 31, 2024. As of September 30, 2025 and December 31, 2024, there were no material transfers between fair value hierarchies. Additionally, there were no changes in the method or significant assumptions used to estimate the fair value of our financial instruments.

Recurring Fair Value Measurements September 30, 2025 (in millions) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Balance as of September 30, 2025
Assets |  |  |  |  |  |  |
U.S. Treasury debt securities(1) | $ | 4.0 |  |  | $ | — |  |  | $ | — |  |  | $ | 4.0 |
Risk management assets | — |  |  | 23.3 |  |  | — |  |  | 23.3 |
Available-for-sale debt securities | — |  |  | 159.0 |  |  | — |  |  | 159.0 |
Equity securities(2)(3) | $ | 8.5 |  |  | $ | — |  |  | $ | — |  |  | $ | 8.5 |
Total | $ | 12.5 |  |  | $ | 182.3 |  |  | $ | — |  |  | $ | 194.8 |
Liabilities |  |  |  |  |  |  |
Risk management liabilities | $ | — |  |  | $ | 6.5 |  |  | $ | — |  |  | $ | 6.5 |
Total | $ | — |  |  | $ | 6.5 |  |  | $ | — |  |  | $ | 6.5 |

(1)Treasury bills are presented in "Cash and cash equivalents" and "Restricted cash" on the Consolidated Balance Sheets.
(2)Equity securities are in a high dividend equity fund and are valued using market prices in active markets. Level 1 instrument valuations are obtained from real-time quotes for transactions in active exchange markets involving identical assets. Equity securities are presented in "Other Investments" on the Consolidated Balance Sheets.
(3)As of September 30, 2025, the investment cost of equity securities measured at fair value was $7.9 million, gross unrealized gains were $0.6 million, and the fair value was $8.5 million.

Recurring Fair Value Measurements December 31, 2024 (in millions) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Balance as of December 31, 2024
Assets |  |  |  |  |  |  |
U.S. Treasury debt securities(1) | $ | 80.1 |  |  | $ | — |  |  | $ | — |  |  | $ | 80.1 |
Risk management assets | — |  |  | 27.0 |  |  | — |  |  | 27.0 |
Available-for-sale debt securities | — |  |  | 86.7 |  |  | — |  |  | 86.7 |
Total | $ | 80.1 |  |  | $ | 113.7 |  |  | $ | — |  |  | $ | 193.8 |
Liabilities |  |  |  |  |  |  |
Risk management liabilities | $ | — |  |  | $ | 3.5 |  |  | $ | — |  |  | $ | 3.5 |
Total | $ | — |  |  | $ | 3.5 |  |  | $ | — |  |  | $ | 3.5 |

(1)Treasury bills are presented in "Cash and cash equivalents" and "Restricted cash" on the Consolidated Balance Sheets.
Level 1- When utilized, exchange-traded derivative contracts are based on unadjusted quoted prices in active markets and are classified within Level 1. These financial assets and liabilities are secured with cash on deposit with the exchange; therefore, nonperformance risk has not been incorporated into these valuations. These financial assets and liabilities are deemed to be cleared and settled daily by NYMEX as the related cash collateral is posted with the exchange. As a result of this exchange rule, NYMEX derivatives are considered to have no fair value at the balance sheet date for financial reporting purposes, and are presented in Level 1 net of posted cash; however, the derivatives remain outstanding and are subject to future commodity price fluctuations until they are settled in accordance with their contractual terms.
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
Level 2- Certain non-exchange-traded derivatives are valued using broker or over-the-counter, on-line exchanges. In such cases, these non-exchange-traded derivatives are classified within Level 2. Non-exchange-based derivative instruments include swaps, forwards, and options. In certain instances, these instruments may utilize models to measure fair value taking into consideration credit risk. We use a similar model to value similar instruments. Valuation models utilize various inputs that include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, other observable inputs for the asset or liability and market-corroborated inputs, (i.e., inputs derived principally from or corroborated by observable market data by correlation or other means). Where observable inputs are available for substantially the full term of the asset or liability, the instrument is categorized within Level 2.
Level 3- Certain derivatives trade in less active markets with a lower availability of pricing information and models may be utilized in the valuation. When such inputs have a significant impact on the measurement of fair value, the instrument is categorized within Level 3.
Risk Management Assets and Liabilities. Risk management assets and liabilities include exchange-traded NYMEX futures and NYMEX options and non-exchange-based forward purchase contracts. NIPSCO and Columbia of Pennsylvania have entered into long-term forward natural gas purchase instruments to lock in a fixed price for natural gas customers. We value these contracts using a pricing model that incorporates market-based information when available, as these instruments trade less frequently and are classified within Level 2 of the fair value hierarchy. For additional information, see Note 10, "Risk Management Activities."
Available-for-Sale Debt Securities. Available-for-sale debt securities are investments pledged as collateral for trust accounts related to our wholly owned insurance company. We value U.S. Treasury, corporate debt and mortgage-backed securities using a matrix pricing model that incorporates market-based information. These securities trade less frequently and are classified within Level 2.
Our available-for-sale debt securities impairments are recognized periodically using an allowance approach. At each reporting date, we utilize a quantitative and qualitative review process to assess the impairment of available-for-sale debt securities at the individual security level. For securities in a loss position, we evaluate our intent to sell or whether it is more-likely-than-not that we will be required to sell the security prior to the recovery of its amortized cost. If either criteria is met, the loss is recognized in earnings immediately, with the offsetting entry to the carrying value of the security. If both criteria are not met, we perform an analysis to determine whether the unrealized loss is related to credit factors. The analysis focuses on a variety of factors that include, but are not limited to, downgrade on ratings of the security, defaults in the current reporting period or projected defaults in the future, the security's yield spread over treasuries, and other relevant market data. If the unrealized loss is not related to credit factors, it is included in other comprehensive income. If the unrealized loss is related to credit factors, the loss is recognized as credit loss expense in earnings during the period, with an offsetting entry to the allowance for credit losses. The amount of the credit loss recorded to the allowance account is limited by the amount at which the security's fair value is less than its amortized cost basis. If certain amounts recorded in the allowance for credit losses are deemed uncollectible, the allowance on the uncollectible portion will be charged off, with an offsetting entry to the carrying value of the security. Subsequent improvements to the estimated credit losses of available-for-sale debt securities will be recognized immediately in earnings. Continuous credit monitoring and portfolio credit balancing mitigates our risk of credit losses on our available-for-sale debt securities.
29

The amortized cost, gross unrealized gains and losses, allowance for credit losses, and fair value of available-for-sale securities at September 30, 2025 and December 31, 2024 were:

September 30, 2025 (in millions) | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses(1) |  | Allowance for Credit Losses |  | Fair Value
Available-for-sale debt securities |  |  |  |  |  |  |  |  |
U.S. Treasury debt securities | 10.6 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 10.6 |
Corporate/Other debt securities | $ | 149.8 |  |  | $ | 2.3 |  |  | $ | (3.6) |  |  | $ | (0.1) |  |  | $ | 148.4 |
Total | $ | 160.4 |  |  | $ | 2.3 |  |  | $ | (3.6) |  |  | $ | (0.1) |  |  | $ | 159.0 |
December 31, 2024 (in millions) | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses(2) |  | Allowance for Credit Losses |  | Fair Value
Available-for-sale debt securities |  |  |  |  |  |  |  |  |
Corporate/Other debt securities | $ | 91.9 |  |  | $ | 0.5 |  |  | $ | (5.6) |  |  | $ | (0.1) |  |  | $ | 86.7 |
Total | $ | 91.9 |  |  | $ | 0.5 |  |  | $ | (5.6) |  |  | $ | (0.1) |  |  | $ | 86.7 |

(1)Fair value of U.S. Treasury debt securities and Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $1.5 million and $55.9 million at September 30, 2025.
(2)Fair value of Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $70.1 million at December 31, 2024.
The cost of maturities sold is based upon specific identification. Net realized gains and losses on available-for-sale securities were de minimis and $0.1 million for the three and nine months ended September 30, 2025, respectively, and $0.1 million and $0.5 million for the three and nine months ended September 30, 2024.
Equity Investments. Investments measured at net asset value per share (or its equivalent) as a practical expedient have not been classified in the fair value hierarchy. These investments represent holdings in a single private investment fund that are redeemable at the election of the holder. As of September 30, 2025, the Company holds $17.9 million of equity investments measured at net asset value.
Non-recurring Fair Value Measurements
We measure the fair value of certain assets, primarily goodwill, on a non-recurring basis, typically when events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable.
B. Other Fair Value Disclosures for Financial Instruments. The carrying amount of cash and cash equivalents, restricted cash, notes receivable, customer deposits and short-term borrowings is a reasonable estimate of fair value due to their liquid or short-term nature. Our long-term borrowings are recorded at historical amounts.
The following method and assumptions were used to estimate the fair value of each class of financial instruments.
Long-term Debt. The fair value of outstanding long-term debt is estimated based on the quoted market prices for the same or similar securities. Certain premium costs associated with the early settlement of long-term debt are not taken into consideration in determining fair value. These fair value measurements are classified within Level 2 of the fair value hierarchy. As of September 30, 2025, there was no change in the method or significant assumptions used to estimate the fair value of long-term debt.
The carrying amount and estimated fair values of these financial instruments were as follows:

(in millions) | Carrying Amount as of September 30, 2025 |  | Estimated Fair Value as of September 30, 2025 |  | Carrying Amount as of Dec. 31, 2024 |  | Estimated Fair Value as of Dec. 31, 2024
Long-term debt (including current portion) | $ | 14,503.4 |  |  | $ | 14,050.3 |  |  | $ | 13,355.7 |  |  | $ | 12,505.2 |

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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
12. Income Taxes
Our interim effective tax rates reflect the estimated annual effective tax rates for 2025 and 2024 applied to year-to-date pretax income, adjusted for tax expense associated with certain discrete items. The effective tax rates for the three months ended September 30, 2025 and 2024 were 16.1% and 14.1%, respectively. The effective tax rates for the nine months ended September 30, 2025 and 2024 were 17.0% and 15.4%, respectively. These effective tax rates differ from the federal statutory tax rate of 21% primarily due to net income attributable to noncontrolling interest, amortization of excess deferred income taxes, federal tax credits net of deferred regulatory liabilities, state income taxes, and other permanent book-to-tax differences.
The increase in the three month effective tax rate of 2.0% in 2025 compared to 2024 is primarily driven by changes in net income attributable to noncontrolling interest, lower AFUDC equity and increases to other permanent differences, partially offset by lower state income taxes.
The increase in the nine month effective tax rate of 1.6% in 2025 compared to 2024 is primarily driven by lower AFUDC equity and changes in net income attributable to noncontrolling interest.
As of September 30, 2025, there have been no material changes to our unrecognized tax benefits or possible changes that could reasonably be expected to occur during the next twelve months. See Note 15 to the Company’s Consolidated Financial Statements in the Annual Report on Form 10-K for the year ended December 31, 2024, for a discussion of these unrecognized tax benefits.
On July 4, 2025, President Donald J. Trump enacted the One Big Beautiful Bill Act ("OBBBA"), which introduced significant federal tax and spending reforms. After evaluation, management determined that the OBBBA does not currently have a material effect on the Company’s financial statements. The Company will continue to monitor the bill’s implementation and will update its financial disclosures as needed should material impacts arise under applicable accounting standards.
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
13. Pension and Other Postemployment Benefits
We provide defined contribution plans and noncontributory defined benefit retirement plans that cover certain of our employees. Benefits under the defined benefit retirement plans reflect the employees' compensation, years of service and age at retirement. Additionally, we provide health care and life insurance benefits for certain retired employees. Certain active employees may become eligible for these benefits if they reach retirement age while working for us. The expected cost of such benefits is accrued during the employees' years of service. We determined that, for certain rate-regulated subsidiaries, the future recovery of postretirement benefit costs is probable, and we record regulatory assets and liabilities for amounts that would otherwise have been recorded to expense or accumulated other comprehensive loss. Current rates of rate-regulated companies include postretirement benefit costs, including amortization of the regulatory assets and liabilities that arose prior to inclusion of these costs in rates. For most plans, cash contributions are remitted to grantor trusts.
For the nine months ended September 30, 2025 and 2024, we contributed $1.5 million and $1.9 million, respectively, to our pension plans and $15.4 million and $18.3 million, respectively, to our OPEB plans.
The following table provides the components of the plans' actuarially determined net periodic benefit cost for the three and nine months ended September 30, 2025 and 2024:

| Pension Benefits |  | OPEB
Three Months Ended September 30, (in millions) | 2025 |  | 2024 |  | 2025 |  | 2024
Components of Net Periodic Benefit Cost(1) |  |  |  |  |  |  |
Service cost | $ | 4.9 |  |  | $ | 5.5 |  |  | $ | 1.0 |  |  | $ | 1.3 |
Interest cost | 16.0 |  |  | 16.3 |  |  | 5.6 |  |  | 5.5 |
Expected return on assets | (23.1) |  |  | (23.8) |  |  | (4.2) |  |  | (4.0) |
Amortization of prior service credit | — |  |  | — |  |  | (0.4) |  |  | (0.4) |
Recognized actuarial loss | 6.4 |  |  | 7.2 |  |  | 0.4 |  |  | 0.8 |
Settlement loss | 5.6 |  |  | 5.9 |  |  | — |  |  | — |
Total Net Periodic Benefit Cost | $ | 9.8 |  |  | $ | 11.1 |  |  | $ | 2.4 |  |  | $ | 3.2 |
(1)The service cost component and all non-service cost components of net periodic benefit (income) cost are presented in "Operation and maintenance" and "Other, net," respectively, on the Condensed Statements of Consolidated Income (unaudited).

| Pension Benefits |  | OPEB
Nine Months Ended September 30, (in millions) | 2025 |  | 2024 |  | 2025 |  | 2024
Components of Net Periodic Benefit Cost(1) |  |  |  |  |  |  |
Service cost | $ | 14.7 |  |  | $ | 16.4 |  |  | $ | 3.0 |  |  | $ | 3.9 |
Interest cost | 48.0 |  |  | 48.9 |  |  | 16.8 |  |  | 16.4 |
Expected return on assets | (69.3) |  |  | (71.4) |  |  | (12.6) |  |  | (12.0) |
Amortization of prior service credit | — |  |  | — |  |  | (1.2) |  |  | (1.2) |
Recognized actuarial loss | 19.2 |  |  | 21.6 |  |  | 1.2 |  |  | 2.4 |
Settlement loss | 5.6 |  |  | 5.9 |  |  | — |  |  | — |
Total Net Periodic Benefit Cost | $ | 18.2 |  |  | $ | 21.4 |  |  | $ | 7.2 |  |  | $ | 9.5 |
(1)The service cost component and all non-service cost components of net periodic benefit (income) cost are presented in "Operation and maintenance" and "Other, net," respectively, on the Condensed Statements of Consolidated Income (unaudited).

During the three months ended September 30, 2025, one of our qualified pension plans met the requirement for settlement accounting. A one-time settlement charge of $5.6 million was recorded during the three months ended September 30, 2025.
In August 2025, we communicated to plan participants of one of our OPEB plans the intention to move from a group self-insured Medicare supplemental health plan to a Sponsored Health Reimbursement Account, with eligible retirees electing coverage through a Healthcare Exchange. This change will become effective on January 1, 2026. Given the intention of the plan and communication to participants, this was considered a plan amendment at the time of communication. This plan amendment triggered remeasurement of this plan, resulting in a decrease to the OPEB regulatory asset of $5.7 million, a decrease to OPEB
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
liability of $23.3 million, and an increase to accumulated other comprehensive loss of $17.6 million. Net periodic OPEB benefit cost for 2025 decreased by $1.7 million as a result of the interim remeasurement.
In line with the remeasurement, key inputs, economic assumptions, and demographic assumptions changed to calculate the updated OPEB benefit obligation and the net periodic benefit cost at the interim remeasurement date for the plan that triggered settlement accounting. For remeasurement, we used a weighted-average discount rate of 5.53%, a weighted-average health care trend rate of 9.97% for next year and ultimate trend rate of 4.75% to be reached in 2034, and weighted-average expected return on assets of 6.88%.
14. Other Commitments and Contingencies
A. Guarantees and Indemnities. We and certain of our subsidiaries enter into various agreements providing financial or performance assurance to third parties on behalf of certain subsidiaries as a part of normal business. Such agreements include guarantees and stand-by letters of credit. These agreements are entered into primarily to support or enhance the creditworthiness otherwise attributed to a subsidiary on a stand-alone basis, thereby facilitating the extension of sufficient credit to accomplish the subsidiaries' intended commercial purposes. As of September 30, 2025 and December 31, 2024, we had issued letters of credit of $119.0 million and $9.4 million, respectively, for the benefit of third parties.
We provide guarantees related to our future performance under BTAs for our renewable generation projects. At September 30, 2025 and December 31, 2024, our guarantees for multiple BTAs totaled $29.2 million and $1,127.5 million, respectively. The amount of each guaranty will decrease upon the substantial completion of the construction of the facilities. See ''- D. Other Matters - Generation Transition,'' below for more information.
We provide guarantees related to some of our rail and pipeline service agreements. As of September 30, 2025 and December 31, 2024, if we do not meet our contractual obligations under the terms of these agreements we would be required to pay up to a maximum of $52.0 million and $61.7 million, respectively.
B. Legal Proceedings. From time to time, various legal and regulatory claims and proceedings are pending or threatened against the Company and its subsidiaries. While the amounts claimed may be substantial, the Company is unable to predict with certainty the ultimate outcome of such claims and proceedings. The Company establishes reserves whenever it believes it to be appropriate for pending litigation matters. However, the actual results of resolving the pending litigation matters may be substantially higher than the amounts reserved. If one or more matters were decided against us, the effects could be material to our results of operations in the period in which we would be required to record or adjust the related liability and could also be material to our cash flows in the periods that we would be required to pay such liability. Due to the inherent uncertainty of litigation, there can be no assurance that the resolution of any particular claim, proceeding or investigation would not have a material adverse effect on our results of operations, financial position or liquidity.
Other Claims and Proceedings. We are also party to other claims, regulatory and legal proceedings arising in the ordinary course of business in each state in which we have operations, and based upon an investigation of these matters and discussion with legal counsel, we believe the ultimate outcome of such other legal proceedings to be individually, or in aggregate, not material at this time.
C. Environmental Matters. Our operations are subject to environmental statutes and regulations related to air quality, water quality, hazardous waste and solid waste. We believe that we are in substantial compliance with the environmental regulations currently applicable to our operations.
It is management's continued intent to address environmental issues in cooperation with regulatory authorities in such a manner as to achieve mutually acceptable compliance plans. However, there can be no assurance that fines and penalties will not be incurred. Management expects a majority of environmental assessment and remediation costs and asset retirement costs, further described below, to be recoverable through rates.
As of September 30, 2025 and December 31, 2024, we had recorded a liability of $84.6 million and $91.8 million, respectively, to cover environmental remediation at various sites. This liability is included in "Other accruals" and "Other noncurrent liabilities and deferred credits" in the Condensed Consolidated Balance Sheets (unaudited). We recognize costs associated with environmental remediation obligations when the incurrence of such costs is probable and the amounts can be reasonably estimated. The original estimates for remediation activities may differ materially from the amount ultimately expended. The actual future expenditures depend on many factors, including laws and regulations, the nature and extent of impact and the
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
method of remediation. These expenditures are not currently estimable at some sites. We periodically adjust our liability as information is collected and estimates become more refined.
CERCLA. Our subsidiaries are potentially responsible parties at waste disposal sites under CERCLA and similar state laws. Under CERCLA, each potentially responsible party can be held jointly, severally and strictly liable for the remediation costs as the EPA, or state, can allow the parties to pay for remedial action or perform remedial action themselves and request reimbursement from the potentially responsible parties. Our affiliates have retained CERCLA environmental liabilities, including remediation liabilities, associated with certain current and former operations. At this time, we cannot estimate the full cost of remediating properties that have not yet been investigated, but it is possible that the future costs could be material to the Condensed Consolidated Financial Statements (unaudited).
MGP. We maintain a program to identify and investigate former MGP sites where our subsidiaries or predecessors may have liability. The program has identified 51 such sites where liability is probable. Remedial actions at many of these sites are being overseen by state or federal environmental agencies through consent agreements or voluntary remediation agreements.
We utilize a probabilistic model to estimate our future remediation costs related to MGP sites. The model was prepared with the assistance of a third party and incorporates our experience and general industry experience with remediating MGP sites. We perform an annual update of the model in the second quarter each year. No material changes to the estimated future remediation costs were identified during the update completed as of June 30, 2025. Our total estimated liability related to the facilities subject to remediation was $77.3 million and $86.4 million at September 30, 2025 and December 31, 2024, respectively. The liability represents our best estimate of the probable cost to remediate the MGP sites. Our model indicates that it is reasonably possible that remediation costs could vary by as much as $16.5 million and $16.3 million at September 30, 2025 and December 31, 2024, respectively, in addition to the costs noted above. Remediation costs are estimated based on the best available information, applicable remediation standards at the balance sheet date and experience with similar facilities.
CCRs. NIPSCO continues to meet the compliance requirements established by the EPA for the regulation of CCRs. The CCR rule requirements currently in effect required revisions to previously recorded legal obligations associated with the retirement of certain NIPSCO facilities. The actual asset retirement costs related to the CCR rule may vary substantially from the estimates used to record the increased asset retirement obligation due to the uncertainty about the requirements that will be established by environmental authorities, compliance strategies that will be used, and the preliminary nature of available data used to estimate costs. As allowed by the rule, NIPSCO will continue to collect data over time to determine the specific compliance solutions and associated costs and, as a result, the actual costs may vary.
On May 8, 2024, the EPA finalized changes to the current CCR regulations ("Legacy CCR Rule"), which address inactive surface impoundments at inactive facilities, referred to as legacy impoundments, and CCR management units ("CCRMUs") at inactive and active facilities. The rule largely requires these newly regulated units to conform to existing requirements, such as groundwater monitoring, closure requirements, and post-closure care. In the second quarter of 2025, we accrued an additional $38.8 million to cover probable and estimable compliance activities associated with the Legacy CCR Rule. NIPSCO continues to assess whether existing legal obligations associated with the retirement of certain facilities must be revised and to estimate probable additional required asset retirement costs. NIPSCO expects to receive recovery of any such costs through existing and future depreciation rates.
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
D. Other Matters.
Generation Transition. NIPSCO has executed several BTAs with developers to construct renewable generation facilities. In October 2024, NIPSCO contracted with a developer to convert the previously approved Templeton PPA to a BTA and in February 2025 filed a CPCN with the IURC seeking approval of the full ownership BTA structure. In September 2025, the IURC granted NIPSCO a CPCN to acquire Templeton through the full ownership BTA structure. NIPSCO's purchase obligation under Templeton is dependent on timely completion of construction. Certain agreements require NIPSCO to make partial payments upon the developer's completion of significant construction milestones.
In January 2025, the Fairbanks project achieved mechanical completion, resulting in NIPSCO making a $336.6 million payment to the developer. In May 2025, the Fairbanks project achieved substantial completion, resulting in NIPSCO making a $141.4 million payment to the developer in June 2025.
In January 2025, the Dunns Bridge II project achieved substantial completion, resulting in NIPSCO making a $217.6 million payment to the developer in February 2025.
In June 2025, the Gibson project achieved mechanical completion, resulting in NIPSCO making a $262.4 million payment to the developer. In August 2025, the Gibson project achieved substantial completion, resulting in NIPSCO making a $133.7 million payment to the develo per in September 2025.
EPC Agreements. GenCo has entered into certain EPC contracts to construct generation capacity assets to support the Data Center Contract, requiring payments at specified periods. The assets contemplated by these contracts are subject to IURC approval. We may terminate for convenience the EPC Contracts and pay certain incurred project costs and termination fees if the Data Center Contract is terminated or IURC approval of the underlying assets is not obtained.
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
15. Accumulated Other Comprehensive Loss
The following tables display the components of Accumulated Other Comprehensive Loss, net of tax:

(in millions) | Gains and Losses on Securities(1) |  | Gains and Losses on Cash Flow Hedges(1) |  | Pension and OPEB Items(1) |  | Accumulated Other Comprehensive Loss(1)
Balance as of June 30, 2025 | $ | (2.2) |  |  | $ | (13.4) |  |  | $ | (12.6) |  |  | $ | (28.2) |
Other comprehensive income before reclassifications | 1.3 |  |  | — |  |  | 13.8 |  |  | 15.1 |
Amounts reclassified from accumulated other comprehensive loss | — |  |  | (0.1) |  |  | 0.2 |  |  | 0.1 |
Net current-period other comprehensive income (loss) | 1.3 |  |  | (0.1) |  |  | 14.0 |  |  | 15.2 |
Balance as of September 30, 2025 | $ | (0.9) |  |  | $ | (13.5) |  |  | $ | 1.4 |  |  | $ | (13.0) |
(1)All amounts are net of tax. Amounts in parentheses indicate debits. |  |  |  |  |  |  |
(in millions) | Gains and Losses on Securities(1) |  | Gains and Losses on Cash Flow Hedges(1) |  | Pension and OPEB Items(1) |  | Accumulated Other Comprehensive Loss(1)
Balance as of December 31, 2024 | $ | (4.0) |  |  | $ | (13.2) |  |  | $ | (13.2) |  |  | $ | (30.4) |
Other comprehensive income before reclassifications | 3.1 |  |  | — |  |  | 13.9 |  |  | 17.0 |
Amounts reclassified from accumulated other comprehensive loss | — |  |  | (0.3) |  |  | 0.7 |  |  | 0.4 |
Net current-period other comprehensive income (loss) | 3.1 |  |  | (0.3) |  |  | 14.6 |  |  | 17.4 |
Balance as of September 30, 2025 | $ | (0.9) |  |  | $ | (13.5) |  |  | $ | 1.4 |  |  | $ | (13.0) |

(1)All amounts are net of tax. Amounts in parentheses indicate debits.

(in millions) | Gains and Losses on Securities(1) |  | Gains and Losses on Cash Flow Hedges(1) |  | Pension and OPEB Items(1) |  | Accumulated Other Comprehensive Loss(1)
Balance as of June 30, 2024 | $ | (7.6) |  |  | $ | (13.0) |  |  | $ | (13.0) |  |  | $ | (33.6) |
Other comprehensive income (loss) before reclassifications | 3.5 |  |  | 0.4 |  |  | (0.1) |  |  | 3.8 |
Amounts reclassified from accumulated other comprehensive loss | — |  |  | (0.5) |  |  | 0.7 |  |  | 0.2 |
Net current-period other comprehensive income (loss) | 3.5 |  |  | (0.1) |  |  | 0.6 |  |  | 4.0 |
Balance as of September 30, 2024 | $ | (4.1) |  |  | $ | (13.1) |  |  | $ | (12.4) |  |  | $ | (29.6) |
(1)All amounts are net of tax. Amounts in parentheses indicate debits. |  |  |  |  |  |  |
(in millions) | Gains and Losses on Securities(1) |  | Gains and Losses on Cash Flow Hedges(1) |  | Pension and OPEB Items(1) |  | Accumulated Other Comprehensive Loss(1)
Balance as of December 31, 2023 | $ | (7.3) |  |  | $ | (12.8) |  |  | $ | (13.5) |  |  | $ | (33.6) |
Other comprehensive income (loss) before reclassifications | 2.8 |  |  | — |  |  | (0.1) |  |  | 2.7 |
Amounts reclassified from accumulated other comprehensive loss | 0.4 |  |  | (0.3) |  |  | 1.2 |  |  | 1.3 |
Net current-period other comprehensive income (loss) | 3.2 |  |  | (0.3) |  |  | 1.1 |  |  | 4.0 |
Balance as of September 30, 2024 | $ | (4.1) |  |  | $ | (13.1) |  |  | $ | (12.4) |  |  | $ | (29.6) |

(1)All amounts are net of tax. Amounts in parentheses indicate debits.
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Table of Contents
ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
16. Business Segment Information
Our reportable segments reflect the manner in which our business is managed and our resources are allocated. Our operations are divided into two primary reportable segments, the Columbia Operations and the NIPSCO Operations segments. Columbia Operations aggregates the results of the fully regulated and wholly owned subsidiaries of NiSource Gas Distribution Group, Inc. (a holding company that owns Columbia of Kentucky, Columbia of Maryland, Columbia of Ohio, Columbia of Pennsylvania, and Columbia of Virginia). Each Columbia distribution company is an operating segment which we aggregate to form the Columbia Operations reportable segment. NIPSCO Operations includes the results of NIPSCO Holdings I and its majority-owned subsidiaries, including NIPSCO, which has regulated gas and electric operations in northern Indiana.
The remainder of our operations, which are not significant enough on a stand-alone basis to warrant treatment as a reportable segment, are presented as "Corporate and Other" and primarily are comprised of interest expense on holding company debt and unallocated corporate costs and activities. Refer to Note 3, "Revenue Recognition," for additional information on our segments and their sources of revenues. The following table provides information about our reportable segments. We use operating income as the primary measurement of performance for each of the reportable segments and make decisions on financing, dividends and taxes at the corporate level on a consolidated basis. We provide this measure to our CODM, the CEO, who utilizes it to assess performance and allocation of resources at the operating segment level based on budget-to-actual and actual-to-actual variances. Segment revenues include intersegment sales to affiliated subsidiaries, which are eliminated in consolidation. Affiliated sales are recognized on the basis of prevailing market, regulated prices or at levels provided for under contractual agreements. Operating income is derived from revenues and expenses directly associated with each segment.

Three Months Ended September 30, 2025 |  |
(in millions) | Columbia Operations |  | NIPSCO Operations |  | Total of Reportable Segments |  |  |  |
Operating Revenues |  |  |  |  |  |  |  |  |
External Revenue | $ | 484.9 |  |  | $ | 787.0 |  |  | $ | 1,271.9 |  |  |  |  |
Intersegment Revenue | 3.3 |  |  | 0.3 |  |  | 3.6 |  |  |  |  |
Total Operating Revenue | $ | 488.2 |  |  | $ | 787.3 |  |  | $ | 1,275.5 |  |  |  |  |
Cost of energy | 58.5 |  |  | 135.2 |  |  | 193.7 |  |  |  |  |
O&M | 212.8 |  |  | 215.1 |  |  | 427.9 |  |  |  |  |
Depreciation | 112.7 |  |  | 185.3 |  |  | 298.0 |  |  |  |  |
Total other taxes | 52.0 |  | 19.1 |  | 71.1 |  |  |  |  |
Other segment items(1) | 0.1 |  |  | — |  |  | 0.1 |  |  |  |  |
Operating Income | $ | 52.1 |  |  | $ | 232.6 |  |  | $ | 284.7 |  |  |  |  |

(1)Other segment items consists of Loss on Sale or Impairment of Assets and other segment income or expenses deemed insignificant which are used to reach our measurement of segment profit or loss, Operating Income.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Three Months Ended September 30, 2024 |  |
(in millions) | Columbia Operations |  | NIPSCO Operations |  | Total of Reportable Segments |  |  |  |
Operating Revenues |  |  |  |  |  |  |  |  |
External Revenue | $ | 423.4 |  |  | $ | 652.6 |  |  | $ | 1,076.0 |  |  |  |  |
Intersegment Revenue | 3.3 |  |  | 0.3 |  |  | 3.6 |  |  |  |  |
Total Operating Revenue | 426.7 |  |  | 652.9 |  |  | 1,079.6 |  |  |  |  |
Cost of energy | 34.2 |  |  | 131.7 |  |  | 165.9 |  |  |  |  |
O&M | 202.9 |  |  | 177.7 |  |  | 380.6 |  |  |  |  |
Depreciation | 103.0 |  |  | 156.8 |  |  | 259.8 |  |  |  |  |
Total other taxes | 45.4 |  | 15.4 |  | 60.8 |  |  |  |
Operating Income | $ | 41.2 |  |  | $ | 171.3 |  |  | $ | 212.5 |  |  |  |  |

Nine Months Ended September 30, 2025 |  |
(in millions) | Columbia Operations |  | NIPSCO Operations |  | Total of Reportable Segments |  |  |  |
Operating Revenues |  |  |  |  |  |  |  |  |
External Revenue | $ | 2,326.7 |  |  | $ | 2,409.0 |  |  | $ | 4,735.7 |  |  |  |  |
Intersegment Revenue | 10.0 |  |  | 0.8 |  |  | 10.8 |  |  |  |  |
Total Operating Revenue | $ | 2,336.7 |  |  | $ | 2,409.8 |  |  | $ | 4,746.5 |  |  |  |  |
Cost of energy | 548.7 |  |  | 554.3 |  |  | 1,103.0 |  |  |  |  |
O&M | 663.5 |  |  | 628.1 |  |  | 1,291.6 |  |  |  |  |
Depreciation | 332.6 |  |  | 492.5 |  |  | 825.1 |  |  |  |  |
Total other taxes | 171.4 |  | 55.7 |  | 227.1 |  |  |  |  |
Other segment items(1) | 0.4 |  |  | 0.7 |  |  | 1.1 |  |  |  |  |
Operating Income | $ | 620.1 |  |  | $ | 678.5 |  |  | $ | 1,298.6 |  |  |  |  |

(1)Other segment items consists of Loss on Sale or Impairment of Assets and other segment income or expenses deemed insignificant which are used to reach our measurement of segment profit or loss, Operating Income.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Nine Months Ended September 30, 2024 |  |
(in millions) | Columbia Operations |  | NIPSCO Operations |  | Total of Reportable Segments |  |  |  |
Operating Revenues |  |  |  |  |  |  |  |  |
External Revenue | $ | 1,864.5 |  |  | $ | 2,002.2 |  |  | $ | 3,866.7 |  |  |  |  |
Intersegment Revenue | 9.6 |  |  | 0.8 |  |  | 10.4 |  |  |  |  |
Total Operating Revenue | 1,874.1 |  |  | 2,003.0 |  |  | 3,877.1 |  |  |  |  |
Cost of energy | 319.3 |  |  | 436.3 |  |  | 755.6 |  |  |  |  |
O&M | 604.9 |  |  | 556.5 |  |  | 1,161.4 |  |  |  |  |
Depreciation | 300.6 |  |  | 432.5 |  |  | 733.1 |  |  |  |  |
Total other taxes | 149.5 |  | 47.8 |  | 197.3 |  |  |  |
Other segment items(1) | — |  |  | (0.1) |  |  | (0.1) |  |  |  |  |
Operating Income | $ | 499.8 |  |  | $ | 530.0 |  |  | $ | 1,029.8 |  |  |  |  |

(1)Other segment items consists of (Gain) on Sale or Impairment of Assets and other segment income or expenses deemed insignificant which are used to reach our measurement of segment profit or loss, Operating Income.
The following table provides information about the assets of our reportable segments included in the Condensed Consolidated Balance Sheets (unaudited):

(in millions) | September 30, 2025 |  | December 31, 2024
Assets |  |  |
Columbia Operations | $ | 15,267.9 |  |  | $ | 14,769.5 |
NIPSCO Operations | 17,834.8 |  |  | 15,823.5 |
Corporate and Other | 1,300.2 |  |  | 1,195.1 |
Consolidated Assets | $ | 34,402.9 |  |  | $ | 31,788.1 |

To reconcile the segment tables above to consolidated NiSource:

Three Months Ended September 30, 2025
(in millions) | Total Reportable Segments |  | Corporate and Other |  | Eliminations |  | Consolidated NiSource
Total Operating Revenue | $ | 1,275.5 |  |  | $ | 151.8 |  |  | $ | (154.2) |  |  | $ | 1,273.1 |
Operating Income | 284.7 |  |  | 12.8 |  |  | — |  |  | 297.5 |

Three Months Ended September 30, 2024
(in millions) | Total Reportable Segments |  | Corporate and Other |  | Eliminations |  | Consolidated NiSource
Total Operating Revenue | $ | 1,079.6 |  |  | $ | 145.9 |  |  | $ | (149.2) |  |  | $ | 1,076.3 |
Operating Income | 212.5 |  |  | 5.8 |  |  | — |  |  | 218.3 |

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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Nine Months Ended September 30, 2025
(in millions) | Total Reportable Segments |  | Corporate and Other |  | Eliminations |  | Consolidated NiSource
Total Operating Revenue | $ | 4,746.5 |  |  | $ | 441.8 |  |  | $ | (449.0) |  |  | $ | 4,739.3 |
Operating Income | 1,298.6 |  |  | 21.2 |  |  | — |  |  | 1,319.8 |

Nine Months Ended September 30, 2024
(in millions) | Total Reportable Segments |  | Corporate and Other |  | Eliminations |  | Consolidated NiSource
Total Operating Revenue | $ | 3,877.1 |  |  | $ | 425.1 |  |  | $ | (434.9) |  |  | $ | 3,867.3 |
Operating Income | 1,029.8 |  |  | 8.9 |  |  | — |  |  | 1,038.7 |

17. Other, Net
The following table displays the components of Other, Net included on the Condensed Statements of Consolidated Income (unaudited):

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | 2025 |  | 2024
Interest income | $ | 3.8 |  |  | $ | 3.4 |  |  | $ | 7.3 |  |  | $ | 7.8 |
AFUDC equity | 8.5 |  |  | 32.1 |  |  | 26.3 |  |  | 56.7 |
Pension and other postretirement non-service cost | (5.7) |  |  | (5.9) |  |  | (11.1) |  |  | (10.2) |
Tax penalties | 5.3 |  |  | (0.5) |  |  | (3.9) |  |  | (0.5) |
Miscellaneous | (2.0) |  |  | 0.1 |  |  | (2.4) |  |  | (2.4) |
Total Other, net | $ | 9.9 |  |  | $ | 29.2 |  |  | $ | 16.2 |  |  | $ | 51.4 |

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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
18. Supplemental Disclosures of Cash Flow Information
The following table displays the components of Working Capital on the Condensed Statements of Consolidated Cash Flows (unaudited):

| Nine Months Ended September 30, |  |
(in millions) | 2025 |  | 2024 |  |  |  |
Accounts receivable | $ | 263.3 |  |  | $ | 290.0 |  |  |  |  |
Inventories | (86.2) |  |  | 101.3 |  |  |  |  |
Accounts payable | (223.5) |  |  | (182.6) |  |  |  |  |
Customer deposits and credits | 4.6 |  |  | (32.8) |  |  |  |  |
Taxes accrued | 7.3 |  |  | (31.0) |  |  |  |  |
Interest accrued | 40.9 |  |  | 11.0 |  |  |  |  |
Exchange gas receivable/payable | 59.8 |  |  | (161.6) |  |  |  |  |
Other accruals | (20.4) |  |  | (17.8) |  |  |  |  |
Prepayments and other current assets | (45.4) |  |  | (61.2) |  |  |  |  |
Accrued compensation and employee benefits | (26.4) |  |  | (1.1) |  |  |  |  |
Total change in working capital | $ | (26.0) |  |  | $ | (85.8) |  |  |  |  |

| Nine Months Ended September 30,
(in millions) | 2025 |  | 2024
Non-cash transactions: |  |  |
Capital expenditures included in current liabilities | $ | 408.2 |  |  | $ | 348.0 |
Dividends declared but not paid | 137.4 |  |  | 125.3 |

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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
19. Subsequent Event
Minority Equity Interest Sale
On October 28, 2025, NiSource issued a 19.9% indirect equity interest in NiSource’s wholly-owned subsidiary GenCo to BIP Orion Holdco L.P. and BIP Orion Holdco II L.P., affiliates of Blackstone (collectively, “Investor”), in exchange for $35.2 million. On October 28, 2025, simultaneously with issuance of the 19.9% indirect equity interest in GenCo, Investor, Generation Holdings I, Generation Holdings II and NiSource entered into an Amended and Restated Limited Liability Company Agreement of Generation Holdings II (the “LLC Agreement”).
The LLC Agreement establishes, among other things, governance rights, exit rights, requirements for additional capital contributions, mechanics for distributions, and other arrangements for Generation Holdings II. Specifically, under the terms of the LLC Agreement, Investor will provide up to $1.325 billion in additional capital contributions over a seven-year period, which obligation is backed by an Equity Commitment Letter from Blackstone or an affiliate thereof. Under the LLC Agreement, Investor is entitled to appoint two directors to the board of directors of Generation Holdings II (the “Board”) so long as Investor (together with any approved affiliate) holds at least a 17.5% Percentage Interest (as defined in the LLC Agreement). Investor is expected to appoint two directors to the Board, such that the Board will be comprised of seven directors, two appointed by Investor and five appointed by NiSource. The LLC Agreement also contains certain investor protections, including, among other things, requiring Investor approval for Generation Holdings II to take certain major actions. In addition, the LLC Agreement contains certain terms surrounding transfer rights and other obligations applicable to both Investor and NiSource. Under the LLC Agreement, Generation Holdings II has agreed that, so long as Investor holds a 14.9% or greater Percentage Interest in Generation Holdings II, Generation Holdings II, NIPSCO Holdings II (as defined below) and/or their respective subsidiaries will be the exclusive vehicles for all power, storage and generation requirements for data center customers within NIPSCO’s service territory.
On October 28, 2025, the members of NIPSCO Holdings II entered into a Third Amended and Restated Limited Liability Company Agreement of NIPSCO Holdings II (the "Amended LLC Agreement"), which, among other changes, increased the amount and time period for additional mandatory capital contributions required to be contributed by Investor by $175 million and seven years, which obligation is backed by an Equity Commitment Letter from Blackstone or an affiliate thereof, and amended certain provisions to facilitate NIPSCO Holdings II and its subsidiaries’ provision of electric service to data center customers (and related activities) and their related contracts and arrangements with Generation Holdings II and its subsidiaries.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
NiSource Inc.

Index | Page
Executive Summary | 44
Summary of Consolidated Financial Results | 47
Results and Discussion of Segment Operations | 48
Columbia Operations | 49
NIPSCO Operations | 52
Liquidity and Capital Resources | 57
Regulatory, Environmental and Safety Matters | 62
Market Risk Disclosures | 65
Other Information | 66

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
EXECUTIVE SUMMARY
This Management's Discussion and Analysis of Financial Condition and Results of Operations ("Management’s Discussion") includes management’s analysis of past financial results and certain potential factors that may affect future results, potential future risks and approaches that may be used to manage those risks. See "Note regarding forward-looking statements" at the beginning of this report for a list of factors that may cause results to differ materially.
Management's Discussion is designed to provide an understanding of our operations and financial performance and should be read in conjunction with our Condensed Consolidated Financial Statements (unaudited) included in this report and our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.
We are an energy holding company under the Public Utility Holding Company Act of 2005 whose utility subsidiaries are fully regulated natural gas and electric utility companies serving customers in six states. We generate substantially all of our operating income through these rate regulated businesses. Our businesses are summarized for financial reporting purposes into two primary reportable segments: Columbia Operations and NIPSCO Operations. Refer to ''Note 16, "Business Segment Information," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for further discussion of our business segments.
Our vision is to be a premier, innovative and trusted energy partner. We exist to deliver safe, reliable energy that drives value to our customers. In order to achieve this goal, we seek to develop strategies that benefit all stakeholders as we (i) support long-term infrastructure investment and safety programs to better serve our customers, (ii) align our tariff structures with our cost structure, and (iii) drive value and enable growth in an evolving energy ecosystem. These strategies focus on improving safety and reliability, enhancing customer experience, pursuing regulatory and legislative initiatives to increase accessibility for customers currently not on our gas and electric service, ensuring customer affordability and reducing emissions while generating sustainable returns. The safety of our customers, communities and employees remains our focus. Serving as a guiding practice for our SMS, NiSource is certified in conformance to the American Petroleum Institute Recommended Practice 1173, which is the foundation to our journey towards operational excellence.
Data Center Contract and Strategy:
Data Center Contract
On September 18, 2025, NIPSCO entered into an agreement (the “Data Center Contract”) with a wholly-owned subsidiary of a large publicly traded company (the “Customer”), under which NIPSCO will provide electricity to Customer’s data centers. Under the Data Center Contract, which is subject to IURC approval, NIPSCO will provide electric service to the Customer pursuant to a capacity commitment beginning in 2027 and increasing annually to 2,400 MW by the end of 2032 and will construct up to 3,000 MW of dispatchable generation to provide such electric service. The Data Center Contract’s initial term ends 15 years after the initial energization of Customer’s initial data center. Starting January 1, 2027, Customer will regularly pay NIPSCO a fixed capacity charge and certain pass-through charges. The Customer’s publicly traded, investment-grade parent company has guaranteed the Customer’s payment obligations. These charges are structured to provide us with a return of our invested capital over the fifteen-year initial term. In addition, the Data Center Contract contains provisions for adjustment of the charges designed to provide us with an unlevered internal rate of return on our invested capital over the initial term within a defined range, which we expect over the life of the Data Center Contract to result in an overall realized return greater than that of NIPSCO’s current electric operations, driven by execution and financing. Our realized return may be impacted by factors such as construction costs, operating performance, financing costs and other variables. NIPSCO will also propose to the IURC a mechanism to pass savings back to retail customer for use of the existing system which is expected to begin in 2027. Refer to Part II, Item 1A, “Risk Factors” for a discussion of certain of these factors and other risks relating to the Data Center Contract.
In order to meet demand under the Data Center Contract, NIPSCO plans to enter into a PPA with GenCo, which is subject to IURC approval and which is expected to contain terms and provisions substantially similar to the Data Center Contract, such that economic benefits (except savings that are expected to be passed to retail customers as described above) and obligations of the Data Center Contract as they relate to the Generation Assets (as defined below) are expected to be borne by GenCo and NiSource, as GenCo’s ultimate parent company, rather than NIPSCO.
GenCo plans to construct 400 MW of new battery storage and a new power generation facility consisting of two 1,300 MW combined-cycle, natural gas-fired turbines, which are expected to reach commercial operation between 2028 and 2032 (such assets, collectively, the “Generation Assets”). GenCo has entered into engineering, procurement and construction contracts (the “EPC Contracts”), and certain equipment supply contracts, including a contract to acquire turbines, with respect to the
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
construction of the Generation Assets. The aggregate cost of the Generation Assets, together with the cost to develop related transmission infrastructure (collectively, the “Contract Assets”), is currently estimated to be approximately $7 billion. The EPC Contracts provide certain protections against cost overruns, and any excess costs with respect to the EPC Contracts beyond those protections, or arising apart from the EPC Contracts are, unless otherwise agreed by the parties, shared by Customer and NIPSCO (for transmission) and GenCo (for generation). If the Contract Assets are delivered into service late or do not achieve certain performance-related milestones, Customer is entitled to liquidated damages, subject to a cap and offset against the regular charges paid by the Customer.
Either party may terminate the Data Center Contract upon certain defaults or failure to obtain necessary related approvals from the IURC and FERC. Customer may terminate the Data Center Contract for convenience following certain notice periods and also has a one-time option (exercisable no later than March 31, 2029) to halve the committed capacity under the Data Center Contract to 1,200 MW commencing January 31, 2032. If Customer terminates for convenience, exercises its reduction option or defaults, NIPSCO or its affiliates will be reimbursed for investment costs, subject to agreed caps based on cost estimates by year as of signing. NIPSCO’s aggregate liability, including liquidated damages, is subject to a cap.
NIPSCO’s and GenCo’s operations under the Data Center Contract will be regulated by the IURC in a different way from the regulatory mechanisms applicable to NIPSCO’s historical operations. The terms of the Data Center Contract were determined by commercial negotiation with the Customer. These terms include the charges we receive from the Customer and provisions that may result in adjustments to such charges, including those relating to certain liquidated damages that we may owe Customer in the event of construction delays or capacity shortfalls, the parties’ responsibility to share cost overruns, certain changes in law and force majeure events. The IURC will not regulate the commercial terms of the Data Center Contract; however, the IURC will maintain oversight under the Data Center Contract to ensure NIPSCO provides reliable service to the Customer at just and reasonable rates. In order to recover our investment costs and earn our return under the Data Center Contract, our subsidiaries must efficiently perform their own obligations and must look to the Customer (or its parent guarantor) to perform its obligations, rather than the IURC making use of its traditional rate-making process. In addition, under the Data Center Contract, NIPSCO has direct contractual obligations to the Customer to, among other things, construct the Contract Assets and deliver committed electric capacity in fixed amounts by certain dates.
Data Center Strategy
We continue to experience strong demand from potential data center customers in our northern Indiana service territory and are engaged in negotiations with potential counterparties. Through certain of our subsidiaries, we have entered into certain construction and equipment supply contracts in relation to additional generation and transmission assets that may be used to serve potential future data center customers. As we continue to evaluate our potential data center opportunities, we will continue to focus on the community, financial, operational and regulatory factors that must be managed effectively in order to succeed with our data center strategy. We believe data center development can enhance our local tax base, diversify the employment base across the state of Indiana, and provide greater value to existing customers and shareholders. We continually evaluate ways to effectively manage the potential power demand, generation sources, and transmission capabilities to meet potential further load growth from additional data center customers, while at the same time focusing on our environmental goals.
In order to perform under any further data center contracts, we expect that we would need to develop additional generation and transmission assets and obtain additional financing in connection with such development. For these and other reasons, our ability to successfully execute our data strategy is subject to a number of risks and uncertainties. Refer to Part II, Item 1A, “Risk Factors” for a discussion of certain risks relating to our data center strategy.
Energy Transition: We continue to advance our energy transition strategy, primarily through the continuation and enhancement of existing programs, such as implementing our plan to retire and replace remaining coal-fired electric generation by 2028 with a balanced mix of low- or zero-emission electric generation, ongoing pipe replacement and modernization programs, and deployment of advanced leak detection and repair. Our electric generation transition, initiated through our 2018 Integrated Resource Plan ("2018 Plan") is well underway, and we are continually adjusting to the dynamic energy landscape. As of September 30, 2025, we have placed in service owned renewable and storage projects with combined nameplate capacities of 1,950 MW and 101 MW respectively. Renewable PPA projects with a combined nameplate capacity of 1,000 MW have also been placed in service. In addition, a renewable BTA project with a nameplate capacity of 200 MW, and a renewable PPA project with a nameplate capacity of 195 MW were under development as of September 30, 2025, all of which have received IURC approval. For additional information, see Note 14, "Other Commitments and Contingencies - D. Other Matters". We are continuing to evaluate the development of federal and state executive orders, or other regulatory actions, with respect to our generation transition plans. Absent a directive to remain open, we remain on track to retire R.M. Schahfer's remaining two
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
coal units by the end of 2025. We are taking steps to be prepared to respond to any executive order or regulatory action to the contrary. For additional information, see "Results and Discussion of Operations - NIPSCO Operations," in this Management's Discussion, and see Part I, Item 1A. "Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended December 31, 2024.
NIPSCO's 2021 Integrated Resource Plan ("2021 Plan") lays out a timeline to retire the Michigan City Generating Station by the end of 2028. The 2021 Plan calls for the replacement of the retiring units with a diverse portfolio of resources including demand side management resources, incremental solar, stand-alone energy storage and upgrades to existing facilities at the Sugar Creek Generating Station, among other steps. Additionally, the 2021 Plan calls for a new natural gas peaking facility to replace existing vintage gas peaking facilities at the R.M. Schahfer Generating Station to support system reliability and resiliency, and upgrades to the electric transmission system. Following approval by the IURC in October 2024, the construction of a new 400 MW natural gas peaking generation facility is underway, which is expected to support the planned retirement of the existing vintage gas peaking facilities by the end of 2028. Final retirement dates for these units, as well as Michigan City, will be subject to MISO approval.
NIPSCO's 2024 Integrated Resource Plan ("2024 Plan") was submitted to the IURC on December 9, 2024. The 2024 Plan maintains the retirement decisions and capacity additions identified in the 2018 and 2021 Integrated Resource Plans and calls for additional generation resources through 2029 to support capacity requirements. The 2024 Plan informs future generation investments required to ensure reliability for NIPSCO’s customers and incorporates factors such as anticipated load growth from data centers and other economic development opportunities, EPA emissions rules, and evolving MISO resource accreditation rules. We plan to move as efficiently as possible while maintaining the integrity of our commercial, planning, regulatory, procurement and operational execution processes.
We continue to enhance safety and reduce methane emissions on our gas systems through modernization programs and utilization of advanced leak detection and repair. In addition, we plan to advance other low- or zero-emission energy resources and technologies, such as hydrogen and renewable natural gas.
Transformation: Our enterprise-wide transformation roadmap focuses on operational excellence, safety, operation and maintenance management, and unlocking efficiencies. We are committed to identifying and implementing initiatives that will enable us to streamline work and improve logistics company-wide. These efforts include investments in proven technologies backed with standardized processes that will change the way we plan, schedule, and execute work in the field and how we engage and provide service to our customers. Taken together, all of our optimization initiatives will prioritize safety and continue to optimize our long-term growth profile. Completing the first major milestone of our enterprise-wide transformation roadmap, we concluded all three phases of a WAM ERP program. Phase one of the program implemented the solution within our electric and transmission operations, while the second phase of the program included all gas distribution operations across our operating territories. The third and final phase incorporated our generation assets. This ERP system optimizes the scheduling, dispatch, and execution of our field operations. We will now proceed as planned with our enterprise transformation roadmap by focusing on our customer technology platforms. In addition to transforming technology to enhance our employee and customer experiences, we believe these programs will also ensure we remain on modern systems that help reduce enterprise risk related to end-of-life systems.
Economic Environment: We continue to monitor risks related to order and delivery lead times for construction and other materials, potential unavailability of materials due to global shortages in raw materials, and decreased construction labor productivity in the event of disruptions in the availability of materials. We continue to experience elevated material and supply costs in certain product sourcing categories driven by increased demand and tariffs. To the extent that work plan delays occur or our costs increase, our business operations, results of operations, cash flows, and financial condition could be materially adversely affected.
We are faced with increased competition for employee and contractor talent in the current labor market which has resulted in increased costs to attract and retain talent. We are ensuring that we use all internal human capital programs (development, leadership enablement programs, succession, performance management) to promote retention of our current employees along with having a competitive and attractive appeal for potential recruits. Our flexible work arrangements, where possible, support a broader talent footprint for sourcing talent needed and for remaining competitive.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
We continue to evaluate our financing plan to manage interest expense and exposure to rates. For more information on interest rate risk, see "Market Risk Disclosures".
Summary of Consolidated Financial Results
A summary of our consolidated financial results for the three and nine months ended September 30, 2025 and 2024 are presented below:

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions, except per share amounts) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
Operating Revenues | $ | 1,273.1 |  |  | $ | 1,076.3 |  |  | $ | 196.8 |  |  | $ | 4,739.3 |  |  | $ | 3,867.3 |  |  | $ | 872.0 |
Operating Expenses |  |  |  |  |  |  |  |  |  |  |
Cost of energy | 193.6 |  |  | 165.9 |  |  | (27.7) |  |  | 1,102.9 |  |  | 755.6 |  |  | (347.3) |
Other Operating Expenses | 782.0 |  |  | 692.1 |  |  | (89.9) |  |  | 2,316.6 |  |  | 2,073.0 |  |  | (243.6) |
Total Operating Expenses | 975.6 |  |  | 858.0 |  |  | (117.6) |  |  | 3,419.5 |  |  | 2,828.6 |  |  | (590.9) |
Operating Income | 297.5 |  |  | 218.3 |  |  | 79.2 |  |  | 1,319.8 |  |  | 1,038.7 |  |  | 281.1 |
Total Other Deductions, Net | (169.9) |  |  | (105.4) |  |  | (64.5) |  |  | (435.5) |  |  | (328.8) |  |  | (106.7) |
Income Taxes | 20.6 |  |  | 15.9 |  |  | (4.7) |  |  | 150.1 |  |  | 109.5 |  |  | (40.6) |
Net Income | 107.0 |  |  | 97.0 |  |  | 10.0 |  |  | 734.2 |  |  | 600.4 |  |  | 133.8 |
Net income attributable to noncontrolling interest | 12.3 |  |  | 11.3 |  |  | (1.0) |  |  | 62.5 |  |  | 63.9 |  |  | 1.4 |
Net Income Attributable to NiSource | 94.7 |  |  | 85.7 |  |  | 9.0 |  |  | 671.7 |  |  | 536.5 |  |  | 135.2 |
Preferred dividends and redemption premium | — |  |  | — |  |  | — |  |  | — |  |  | (20.7) |  |  | 20.7 |
Net Income Available to Common Shareholders | 94.7 |  |  | 85.7 |  |  | 9.0 |  |  | 671.7 |  |  | 515.8 |  |  | 155.9 |
Earnings Per Share |  |  |  |  |  |  |  |  |  |  |
Basic Earnings Per Share | $ | 0.20 |  |  | $ | 0.19 |  |  | $ | 0.01 |  |  | $ | 1.42 |  |  | $ | 1.15 |  |  | $ | 0.27 |
Diluted Earnings Per Share | $ | 0.20 |  |  | $ | 0.19 |  |  | $ | 0.01 |  |  | $ | 1.42 |  |  | $ | 1.14 |  |  | $ | 0.28 |

The majority of the costs of energy in both segments are tracked costs that are passed through directly to the customer, resulting in an equal and offsetting amount reflected in operating revenues.
The increase in net income available to common shareholders for the three and nine months ended September 30, 2025 was primarily due to higher revenues driven by our capital investments, partially offset by higher operating expenses, including increased operation and maintenance expense and depreciation expense attributed to our net plant balances, as well as increased interest expense.
For additional information on operating income variance drivers see "Results and Discussion of Segment Operations" for Columbia Operations and NIPSCO Operations in this Management's Discussion.
Income Taxes
Refer to Note 12, "Income Taxes," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for information on income taxes and the change in the effective tax rates for the periods presented.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
RESULTS AND DISCUSSION OF SEGMENT OPERATIONS
Presentation of Segment Information
Columbia Operations aggregates the results of the fully regulated and wholly owned subsidiaries of NiSource Gas Distribution Group, Inc. Each Columbia distribution company is an operating segment which we aggregate to form the Columbia Operations reportable segment. NIPSCO Operations aggregates the results of NIPSCO Holdings I, and its majority-owned subsidiaries, including NIPSCO, which has both regulated gas and electric operations in northern Indiana. The remainder of our operations, which are not significant enough on a stand-alone basis to warrant treatment as a reportable segment, are presented as "Corporate and Other" within the Notes to the Condensed Consolidated Financial Statements (unaudited) and primarily are comprised of interest expense on holding company debt, and unallocated corporate costs and activities.
48

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Columbia Operations
Financial and operational data for the Columbia Operations segment for the three and nine months ended September 30, 2025 and 2024 are presented below.

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
Operating Revenues | $ | 488.2 |  |  | $ | 426.7 |  |  | $ | 61.5 |  |  | $ | 2,336.7 |  |  | $ | 1,874.1 |  |  | $ | 462.6 |
Operating Expenses |  |  |  |  |  |  |  |  |  |  |
Cost of energy | 58.5 |  |  | 34.2 |  |  | (24.3) |  |  | 548.7 |  |  | 319.3 |  |  | (229.4) |
Operation and maintenance | 212.8 |  |  | 202.9 |  |  | (9.9) |  |  | 663.5 |  |  | 604.9 |  |  | (58.6) |
Depreciation and amortization | 112.7 |  |  | 103.0 |  |  | (9.7) |  |  | 332.6 |  |  | 300.6 |  |  | (32.0) |
Loss on sale of assets, net | 0.1 |  |  | — |  |  | (0.1) |  |  | 0.4 |  |  | — |  |  | (0.4) |
Other taxes | 52.0 |  |  | 45.4 |  |  | (6.6) |  |  | 171.4 |  |  | 149.5 |  |  | (21.9) |
Total Operating Expenses | 436.1 |  |  | 385.5 |  |  | (50.6) |  |  | 1,716.6 |  |  | 1,374.3 |  |  | (342.3) |
Operating Income | $ | 52.1 |  |  | $ | 41.2 |  |  | $ | 10.9 |  |  | $ | 620.1 |  |  | $ | 499.8 |  |  | $ | 120.3 |
Revenues |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 329.9 |  |  | $ | 299.2 |  |  | $ | 30.7 |  |  | $ | 1,590.0 |  |  | $ | 1,303.4 |  |  | $ | 286.6 |
Commercial | 95.8 |  |  | 79.2 |  |  | 16.6 |  |  | 531.6 |  |  | 402.4 |  |  | 129.2 |
Industrial | 36.2 |  |  | 32.3 |  |  | 3.9 |  |  | 122.5 |  |  | 106.0 |  |  | 16.5 |
Off-System | 13.8 |  |  | 7.2 |  |  | 6.6 |  |  | 58.9 |  |  | 30.5 |  |  | 28.4 |
Wholesale and Other | 12.5 |  |  | 8.8 |  |  | 3.7 |  |  | 33.7 |  |  | 31.8 |  |  | 1.9 |
Total | $ | 488.2 |  |  | $ | 426.7 |  |  | $ | 61.5 |  |  | $ | 2,336.7 |  |  | $ | 1,874.1 |  |  | $ | 462.6 |
Sales and Transportation (MMDth) |  |  |  |  |  |  |  |  |  |  |
Residential | 8.3 |  |  | 8.3 |  |  | — |  |  | 119.1 |  |  | 102.0 |  |  | 17.1 |
Commercial | 12.9 |  |  | 12.2 |  |  | 0.7 |  |  | 95.6 |  |  | 85.0 |  |  | 10.6 |
Industrial | 72.3 |  |  | 70.9 |  |  | 1.4 |  |  | 207.9 |  |  | 207.9 |  |  | — |
Off-System | 6.1 |  |  | 4.6 |  |  | 1.5 |  |  | 20.7 |  |  | 17.8 |  |  | 2.9 |
Wholesale and Other | — |  |  | — |  |  | — |  |  | 0.2 |  |  | 0.2 |  |  | — |
Total | 99.6 |  |  | 96.0 |  |  | 3.6 |  |  | 443.5 |  |  | 412.9 |  |  | 30.6 |
Heating Degree Days(1) | 27 |  |  | 28 |  |  | (1) |  |  | 3,191 |  |  | 2,659 |  |  | 532 |
Normal Heating Degree Days(1) | 47 |  |  | 53 |  |  | (6) |  |  | 3,214 |  |  | 3,310 |  |  | (96) |
% Warmer than Normal | (43) | % |  | (47) | % |  |  |  | (1) | % |  | (20) | % |  |
% (Warmer) Colder than prior year | (4) | % |  |  |  |  |  | 20 | % |  |  |  |
Columbia Operations Customers |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 2,215,788 |  |  | 2,202,206 |  |  | 13,582 |
Commercial |  |  |  |  |  |  | 187,005 |  |  | 186,087 |  |  | 918 |
Industrial |  |  |  |  |  |  | 1,976 |  |  | 1,975 |  |  | 1 |
Other |  |  |  |  |  |  | 6 |  |  | 4 |  |  | 2 |
Total |  |  |  |  |  |  | 2,404,775 |  |  | 2,390,272 |  |  | 14,503 |

(1) Heating degree figures represent averages of the five jurisdictions served by Columbia Operations.
Comparability of operation and maintenance expenses, depreciation and amortization, and other taxes may be impacted by regulatory, depreciation, and tax trackers that allow for the recovery in rates of certain costs.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Columbia Operations
The underlying reasons for changes in our operating revenues for the three and nine months ended September 30, 2025 compared to the same period in 2024 are presented below.

| Favorable (Unfavorable)
Changes in Operating Revenues (in millions) | Three Months Ended September 30, 2025 vs 2024 |  | Nine Months Ended September 30, 2025 vs 2024 |  |  |  |  |
New rates from base rate proceedings and regulatory capital programs | $ | 31.0 |  |  | $ | 139.3 |  |  |  |  |  |
The effects of weather in 2025 compared to 2024 | 0.2 |  |  | 37.9 |  |  |  |  |  |
The effects of customer growth | 1.2 |  |  | 4.3 |  |  |  |  |  |
The effects of customer usage | 0.9 |  |  | (6.7) |  |  |  |  |  |
Other | (1.1) |  |  | (0.3) |  |  |  |  |  |
Change in operating revenues (before cost of energy and other tracked items) | $ | 32.2 |  |  | $ | 174.5 |  |  |  |  |  |
Operating revenues offset in operating expense |  |  |  |  |  |  |  |
Higher cost of energy billed to customers | 24.2 |  |  | 229.3 |  |  |  |  |  |
Higher tracker deferrals within operation and maintenance, depreciation, and tax | 5.1 |  |  | 58.8 |  |  |  |  |  |
Total change in operating revenues | $ | 61.5 |  |  | $ | 462.6 |  |  |  |  |  |

Weather
In general, we calculate the weather-related revenue variance based on changing customer demand driven by weather variance from normal heating degree days, net of weather and revenue normalization mechanisms. Our composite heating degree days reported do not directly correlate to the weather-related dollar impact on the results of Columbia Operations. Heating degree days experienced during different times of the year or in different operating locations may have more or less impact on volume and dollars depending on when and where they occur. When the detailed results are combined for reporting, there may be weather-related dollar impacts on operations when there is not an apparent or significant change in our aggregated composite heating degree day comparison.
Sales
The increase in total volumes for the nine months ended September 30, 2025, compared to the same period in 2024, is primarily attributable to increased usage by residential and commercial customers as a result of colder weather.
Commodity Price Impact
Cost of energy for the Columbia Operations segment is principally comprised of the cost of natural gas procured on behalf of and sold to customers while providing transportation services. All of our Columbia Operations companies have state-approved recovery mechanisms that provide a means for full recovery of prudently incurred gas costs. These are tracked costs that are passed through directly to the customer, and the gas costs included in revenues are matched with the gas cost expense recorded in the period. Any difference in actual costs incurred and amounts billed to customers is recorded on the Condensed Consolidated Balance Sheets (unaudited) as under-recovered or over-recovered gas cost to be included in future customer billings. Therefore, increases in these tracked operating expenses are offset by increases in operating revenues and have essentially no impact on net income. Certain Columbia Operations companies continue to offer choice opportunities, where customers can choose to purchase gas from a third-party supplier through regulatory initiatives in their respective jurisdictions.
The underlying reasons for changes in our operating expenses for the three and nine months ended September 30, 2025 compared to the same period in 2024 are presented below.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Columbia Operations

| Favorable (Unfavorable) |
Changes in Operating Expenses (in millions) | Three Months Ended September 30, 2025 vs 2024 |  | Nine Months Ended September 30, 2025 vs 2024 |  |  |
Higher depreciation and amortization expense | $ | (9.7) |  |  | $ | (32.0) |  |  |  |
Higher employee and administrative related expenses | (5.1) |  |  | (15.7) |  |  |  |
Higher property tax | (5.0) |  |  | (9.8) |  |  |  |
Other | (1.5) |  |  | 3.3 |  |  |  |
Change in operating expenses (before cost of energy and other tracked items) | $ | (21.3) |  |  | $ | (54.2) |  |  |  |
Operating expenses offset in operating revenue |  |  |  |  |  |
Higher cost of energy billed to customers | (24.2) |  |  | (229.3) |  |  |  |
Higher tracker deferrals within operation and maintenance, depreciation, and tax | (5.1) |  |  | (58.8) |  |  |  |
Total change in operating expense | $ | (50.6) |  |  | $ | (342.3) |  |  |  |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
NIPSCO Operations
Financial and operational data for the NIPSCO Operations segment, which services both gas and electric customers, for the three and nine months ended September 30, 2025 and 2024 are presented below.

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
NIPSCO Operations |  |  |  |  |  |  |  |  |  |  |
Operating Revenues | $ | 787.3 |  |  | $ | 652.9 |  |  | $ | 134.4 |  |  | $ | 2,409.8 |  |  | $ | 2,003.0 |  |  | $ | 406.8 |
Operating Expenses |  |  |  |  |  |  |  |  |  |  |
Cost of energy | 135.2 |  |  | 131.7 |  |  | (3.5) |  |  | 554.3 |  |  | 436.3 |  |  | (118.0) |
Operation and maintenance | 215.1 |  |  | 177.7 |  |  | (37.4) |  |  | 628.1 |  |  | 556.5 |  |  | (71.6) |
Depreciation and amortization | 185.3 |  |  | 156.8 |  |  | (28.5) |  |  | 492.5 |  |  | 432.5 |  |  | (60.0) |
Loss on impairment of assets | — |  |  | — |  |  | — |  |  | 0.7 |  |  | — |  |  | (0.7) |
Gain on sale of assets | — |  |  | — |  |  | — |  |  | — |  |  | (0.1) |  |  | (0.1) |
Other taxes | 19.1 |  |  | 15.4 |  |  | (3.7) |  |  | 55.7 |  |  | 47.8 |  |  | (7.9) |
Total Operating Expenses | 554.7 |  |  | 481.6 |  |  | (73.1) |  |  | 1,731.3 |  |  | 1,473.0 |  |  | (258.3) |
Operating Income | $ | 232.6 |  |  | $ | 171.3 |  |  | $ | 61.3 |  |  | $ | 678.5 |  |  | $ | 530.0 |  |  | $ | 148.5 |
| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
NIPSCO Electric |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 255.6 |  |  | $ | 197.9 |  |  | $ | 57.7 |  |  | $ | 588.1 |  |  | $ | 498.6 |  |  | $ | 89.5 |
Commercial | 211.5 |  |  | 172.7 |  |  | 38.8 |  |  | 533.3 |  |  | 470.0 |  |  | 63.3 |
Industrial | 156.9 |  |  | 125.1 |  |  | 31.8 |  |  | 434.1 |  |  | 361.1 |  |  | 73.0 |
Wholesale and Other | 34.3 |  |  | 43.4 |  |  | (9.1) |  |  | 97.7 |  |  | 112.6 |  |  | (14.9) |
Total | $ | 658.3 |  |  | $ | 539.1 |  |  | $ | 119.2 |  |  | $ | 1,653.2 |  |  | $ | 1,442.3 |  |  | $ | 210.9 |
Sales (GWh) |  |  |  |  |  |  |  |  |  |  |
Residential | 1,115.2 |  |  | 1,079.4 |  |  | 35.8 |  |  | 2,729.9 |  |  | 2,673.1 |  |  | 56.8 |
Commercial | 1,040.2 |  |  | 1,044.7 |  |  | (4.5) |  |  | 2,821.7 |  |  | 2,850.3 |  |  | (28.6) |
Industrial | 2,158.2 |  |  | 2,106.3 |  |  | 51.9 |  |  | 6,328.2 |  |  | 5,884.1 |  |  | 444.1 |
Wholesale and Other | 328.2 |  |  | 327.7 |  |  | 0.5 |  |  | 794.9 |  |  | 818.1 |  |  | (23.2) |
Total | 4,641.8 |  |  | 4,558.1 |  |  | 83.7 |  |  | 12,674.7 |  |  | 12,225.6 |  |  | 449.1 |
Cooling Degree Days | 640 |  |  | 556 |  |  | 84 |  |  | 941 |  |  | 882 |  |  | 59 |
Normal Cooling Degree Days | 588 |  |  | 590 |  |  | (2) |  |  | 852 |  |  | 838 |  |  | 14 |
% Warmer (Colder) than Normal | 9 | % |  | (6) | % |  |  |  | 10 | % |  | 5 | % |  |
% Warmer than prior year | 15 | % |  |  |  |  |  | 7 | % |  |  |  |
NIPSCO Electric Customers |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 432,889 |  |  | 429,382 |  |  | 3,507 |
Commercial |  |  |  |  |  |  | 59,540 |  |  | 59,056 |  |  | 484 |
Industrial |  |  |  |  |  |  | 2,103 |  |  | 2,116 |  |  | (13) |
Wholesale and Other |  |  |  |  |  |  | 705 |  |  | 709 |  |  | (4) |
Total |  |  |  |  |  |  | 495,237 |  |  | 491,263 |  |  | 3,974 |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
NIPSCO Operations

| Three Months Ended September 30, |  | Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
NIPSCO Gas |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 73.7 |  |  | $ | 66.8 |  |  | $ | 6.9 |  |  | $ | 487.5 |  |  | $ | 357.5 |  |  | $ | 130.0 |
Commercial | 32.6 |  |  | 28.5 |  |  | 4.1 |  |  | 183.4 |  |  | 134.0 |  |  | 49.4 |
Industrial | 19.7 |  |  | 16.4 |  |  | 3.3 |  |  | 73.7 |  |  | 56.3 |  |  | 17.4 |
Other | 3.0 |  |  | 2.1 |  |  | 0.9 |  |  | 12.0 |  |  | 12.9 |  |  | (0.9) |
Total | $ | 129.0 |  |  | $ | 113.8 |  |  | $ | 15.2 |  |  | $ | 756.6 |  |  | $ | 560.7 |  |  | $ | 195.9 |
Sales and Transportation Volumes (MMDth) |  |  |  |  |  |  |  |  |  |  |
Residential | 3.6 |  |  | 3.5 |  |  | 0.1 |  |  | 44.9 |  |  | 39.1 |  |  | 5.8 |
Commercial | 4.7 |  |  | 4.9 |  |  | (0.2) |  |  | 32.3 |  |  | 29.2 |  |  | 3.1 |
Industrial | 62.2 |  |  | 60.5 |  |  | 1.7 |  |  | 200.5 |  |  | 192.3 |  |  | 8.2 |
Total | 70.5 |  |  | 68.9 |  |  | 1.6 |  |  | 277.7 |  |  | 260.6 |  |  | 17.1 |
Heating Degree Days | 46 |  |  | 33 |  |  | 13 |  |  | 3,721 |  |  | 3,127 |  |  | 594 |
Normal Heating Degree Days | 71 |  |  | 79 |  |  | (8) |  |  | 3,790 |  |  | 3,860 |  |  | (70) |
% Warmer than Normal | (35) | % |  | (58) | % |  |  |  | (2) | % |  | (19) | % |  |
% (Warmer) Colder than prior year | 39 | % |  | (44) | % |  |  |  | 19 | % |  | (6) | % |  |
NIPSCO Gas Customers |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 804,777 |  |  | 797,711 |  |  | 7,066 |
Commercial |  |  |  |  |  |  | 66,579 |  |  | 66,251 |  |  | 328 |
Industrial |  |  |  |  |  |  | 2,683 |  |  | 2,739 |  |  | (56) |
Total |  |  |  |  |  |  | 874,039 |  |  | 866,701 |  |  | 7,338 |

Comparability of operation and maintenance expenses and depreciation and amortization may be impacted by regulatory and depreciation trackers that allow for the recovery in rates of certain costs.
53

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
NIPSCO Operations
The underlying reasons for changes in our operating revenues for the three and nine months ended September 30, 2025 compared to the same period in 2024 are presented below.

| Favorable (Unfavorable) |
Changes in Operating Revenues (in millions) | Three Months Ended September 30, 2025 vs 2024 |  | Nine Months Ended September 30, 2025 vs 2024 |  |  |
New rates from base rate proceedings, regulatory capital and DSM programs | $ | 110.7 |  |  | $ | 217.6 |  |  |  |
The effects of weather in 2025 compared to 2024 | 11.9 |  |  | 42.5 |  |  |  |
The effects of customer growth | 3.5 |  |  | 9.5 |  |  |  |
Renewable JV revenue, fully offset by JV operating expense and noncontrolling interest net income (loss) | (4.2) |  |  | (11.4) |  |  |  |
The effects of customer usage | (6.5) |  |  | (2.1) |  |  |  |
Other | (0.5) |  |  | (1.6) |  |  |  |
Change in operating revenues (before cost of energy and other tracked items) | $ | 114.9 |  |  | $ | 254.5 |  |  |  |
Operating revenues offset in operating expense |  |  |  |  |  |
Higher cost of energy billed to customers | 3.5 |  |  | 118.0 |  |  |  |
Higher tracker deferrals within operation and maintenance, depreciation and tax | 16.0 |  |  | 34.3 |  |  |  |
Total change in operating revenues | $ | 134.4 |  |  | $ | 406.8 |  |  |  |

Weather
The results of operations for the NIPSCO Operations segment include income from both electric and gas service lines. In general, we calculate the weather-related revenue variance based on changing customer demand driven by weather variance from normal cooling degree days and normal heating degree days, net of NIPSCO Gas' weather normalization mechanism. Our composite cooling and heating degree days reported do not directly correlate to the weather-related dollar impact on the results of NIPSCO Operations. Cooling and heating degree days experienced during different times of the year or in different operating locations may have more or less impact on volume and dollars depending on when they occur. When the detailed results are combined for reporting, there may be weather-related dollar impacts on operations when there is not an apparent or significant change in our aggregated composite cooling and heating degree day comparison.
Sales
The increase in total volumes sold to electric customers for the three months ended September 30, 2025 compared to the same period in 2024 was primarily attributable to increased residential and industrial usage, partially offset by decreased commercial usage. The increase in total volumes sold to electric customers for the nine months ended September 30, 2025 compared to the same period in 2024 was primarily attributable to increased industrial and residential usage due to colder weather and increased customer count, partially offset by decreased commercial and wholesale and other usage
The increase in total volumes sold to gas customers for the three months ended September 30, 2025 compared to the same period in 2024 was primarily attributable to increased usage by industrial customers. The increase in total volumes sold to gas customers for the nine months ended September 30, 2025 compared to the same period in 2024 was primarily attributable to increased usage by industrial and commercial customers, as well as increased residential usage due to colder weather.
Commodity Price Impact
Cost of energy for the NIPSCO Operations segment's electric activities is principally comprised of the cost of coal, natural gas purchased for internal generation of electricity, transportation of coal and natural gas, and the cost of power purchased from generators of electricity for its generation and transmission activities. For its gas distribution activities, NIPSCO Operations' cost of energy is principally comprised of the cost of natural gas procured on behalf of and sold to customers while providing transportation and distribution services. NIPSCO Operations has state-approved recovery mechanisms that provide a means for full recovery of prudently incurred costs of energy. The majority of these costs of energy are passed through directly to the customer, and the costs of energy included in operating revenues are matched with the cost of energy expense recorded in the
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NiSource Inc.
NIPSCO Operations
period. Any difference in actual costs incurred and amounts billed to customers is recorded on the Condensed Consolidated Balance Sheets (unaudited) as under-recovered or over-recovered fuel and gas costs to be included in future customer billings. Therefore, increases in these tracked operating expenses are offset by increases in operating revenues and have essentially no impact on net income.
The underlying reasons for changes in our operating expenses for the three and nine months ended September 30, 2025 compared to the same period in 2024 are presented below.

| Favorable (Unfavorable) |
Changes in Operating Expenses (in millions) | Three Months Ended September 30, 2025 vs 2024 |  | Nine Months Ended September 30, 2025 vs 2024 |  |  |
Higher depreciation and amortization expense driven by new base rates | (28.6) |  |  | $ | (60.8) |  |  |  |
Higher outside services expenses | (4.0) |  |  | (22.0) |  |  |  |
Higher employee and administrative expenses | (10.5) |  |  | (13.6) |  |  |  |
Higher property taxes | (3.0) |  |  | (7.5) |  |  |  |
Higher JV expenses | (1.5) |  |  | (4.9) |  |  |  |
(Higher) lower environmental remediation costs | (0.3) |  |  | 3.0 |  |  |  |
Other | (5.9) |  |  | (1.5) |  |  |  |
Change in operating expenses (before cost of energy and other tracked items) | $ | (53.8) |  |  | $ | (107.3) |  |  |  |
Operating expenses offset in operating revenue |  |  |  |  |  |
Higher cost of energy billed to customers | (3.5) |  |  | (118.0) |  |  |  |
Higher tracker deferrals within operation and maintenance, depreciation and tax | (15.8) |  |  | (33.0) |  |  |  |
Total change in operating expense | $ | (73.1) |  |  | $ | (258.3) |  |  |  |

Electric Supply and Generation Transition
NIPSCO continues to execute on an electric generation transition consistent with the 2018 Plan and 2021 Plan and maintained in the 2024 Plan. The 2024 Plan outlines the path to retire the remaining two coal units at R.M. Schahfer by the end of 2025 and the remaining coal-fired generation at Michigan City by the end of 2028, to be replaced by lower-cost, reliable and cleaner options. NIPSCO is continuing to evaluate the development of federal and state executive orders, or other regulatory actions, with respect to its generation transition plans. Absent a directive to remain open, NIPSCO remain on track to retire R.M. Schahfer's remaining two coal units by the end of 2025. NIPSCO is taking steps to be prepared to respond to any executive order or regulatory action to the contrary.
The current replacement plan primarily includes renewable sources of energy, including wind, solar, battery storage, and flexible natural gas resources to be obtained through a combination of NIPSCO ownership and PPAs. NIPSCO has sold, and may in the future sell, renewable energy credits from its renewable generation to third parties to offset customer costs. Since 2020, five PPA projects (two wind and three solar) and eight owned projects (two wind, four solar and two solar plus storage) have been placed into service totaling 3,051 MW of nameplate capacity, including Dunns Bridge II, Fairbanks, Gibson and Appleseed, which were placed into service in January, May, and August 2025, respectively. NIPSCO has executed several PPAs to purchase 100% of the output from renewable generation facilities at a fixed price per MWh. Each facility supplying the energy has an associated nameplate capacity, and payments under the PPAs do not begin until the associated generation facility is placed into service. See "Executive Summary - Energy Transition" in this Management's Discussion for additional information. We expect the Templeton and Carpenter projects to be placed in service between 2025 and 2027.
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NiSource Inc.
NIPSCO Operations

Remaining Renewables Projects | Transaction Type | Technology | Nameplate Capacity (MW) |  |  |  |
Templeton | BTA | Wind | 200 |  |  |  |
Carpenter | 20 year PPA | Wind | 195 |  |  |  |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Liquidity and Capital Resources
We continually evaluate the availability of adequate financing to fund our ongoing business operations, working capital and core safety and infrastructure investment programs. Our financing is sourced through cash flow from operations and the issuance of debt and/or equity. External debt financing is provided primarily through the issuance of long-term debt, accounts receivable securitization programs and our $1.85 billion commercial paper program, which is backstopped by our committed revolving credit facility with a total availability from third-party lenders of $1.85 billion. We believe these sources provide adequate capital to fund our operating activities and capital expenditures in 2025 and beyond.
As discussed above under “Data Center Contract and Strategy,” the aggregate cost of the Contract Assets is currently estimated to be approximately $7 billion. We expect to finance the construction and development of these assets through a combination of funds received under the Data Center Contract and debt, equity financing raised by NiSource and capital contributions from affiliates of Blackstone to NIPSCO Holdings II and Generation Holdings II in connection with such Blackstone affiliates’ minority interest investments in those entities. For additional information on these minority interest investments, refer to Part II, Item 5 (Other Information) and to our Annual Report on Form 10-K for the year ended December 31, 2024, including Note 19 to our Consolidated Financial Statements included therein. In addition, we may consider other funding sources, structures or partnerships as market conditions and strategic considerations evolve. If we enter into additional data center contracts, we expect that we would need to develop additional generation assets and obtain additional financing in connection with such development.
Sources of financing activities for the current year are as follows:
ATM program
•In February 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,000,000 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $40.10 per share. In September 2025 we settled the forward sale agreement in shares for $80.0 million, based on a net price of $40.02 per share.
•In March 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 1,707,320 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $41.00 per share. In September 2025 we settled the forward sale agreement in shares for $69.9 million, based on a net price of $40.92 per share.
•In June 2025, we executed a forward sale agreement, which allowed us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,518,393 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $39.71 per share. In September 2025 we settled the forward sale agreement in shares for $99.1 million, based on a net price of $39.36 per share.
•As of September 30, 2025, the ATM program had approximately $47.5 million of capacity available.
Long-Term Debt
•On March 27, 2025 we completed the issuance and sale of $750.0 million of 5.850% senior unsecured notes maturing in 2055, which resulted in approximately $739.6 million of net proceeds after discount and debt issuance costs.
•On June 27, 2025, we completed the issuance and sale of an additional $750.0 million of 5.850% senior unsecured notes maturing in 2055 (the "2055 Notes"). The terms of the 2055 Notes, other than the issue date and the price to the public, are identical to the terms of, and constitute a reopening of, our 5.850% senior unsecured notes maturing in 2055 issued on March 27, 2025. With the incremental issuance, we now have $1.5 billion of 5.850% senior unsecured notes maturing in 2055. On June 27, 2025, we also completed the issuance and sale of $900.0 million of 5.350% senior unsecured notes maturing in 2035 (the "2035 Notes"). These issuances of the additional 2055 Notes and the 2035 Notes resulted in approximately $1.616 billion of total net proceeds after discount and debt issuance costs.
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NiSource Inc.
•On August 15, 2025, we repaid $1,250.0 million of 0.95% senior unsecured notes at maturity.
See Note 6, "Equity," Note 7, "Short-Term Borrowings," and Note 8, "Long-Term Debt," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for more information on our financing activities.
Cash Flow Activities
The following table summarizes our cash flow activities:

| Nine Months Ended September 30,
(in millions) | 2025 |  | 2024 |  | Change in 2025 vs 2024
Cash from (used for): |  |  |  |  |
Operating Activities | $ | 1,649.7 |  |  | $ | 1,241.7 |  |  | $ | 408.0 |
Investing Activities | (3,396.6) |  |  | (2,414.5) |  |  | (982.1) |
Financing Activities | 1,667.8 |  |  | (949.5) |  |  | 2,617.3 |

Operating Activities
The increase in cash from operating activities was primarily attributable to year over year changes in exchange gas receivables, higher net income before deferred income taxes and depreciation and a reduction in inventory resulting from an elevated rate of withdrawals due to warmer weather in 2025.
Investing Activities
Year over year increase in investing activities was primarily comprised of milestone payments to renewable generation asset developers for certain of our BTA projects and advanced deposits.
We expect to make capital investments totaling $4.0 billion to $4.3 billion during the 2025 period. In addition to ongoing capital expenditures, these capital investments include advanced deposits for project costs as well as milestone payments to the renewable generation asset developers and excludes $400 million to $500 million of capital investments relating to the Data Center Contract. We also expect to invest approximately $21.0 billion during the 2026-2030 period to support our base business (exclusive of investments relating to the Data Center Contract), including capital investments to support our generation transition strategy, and to invest approximately $6.4 billion during that period to develop the Contract Assets in connection with the Data Center Contract, as set forth in the table below. These forecasted capital investments are subject to continuing review and adjustment. Actual capital investments may vary from these estimates.

(in billions) | 2026 Estimated | 2027 Estimated | 2028 Estimated | 2029 Estimated | 2030 Estimated
Capital Investments (Base Business) | $3.9 - 4.1 | $3.7 - 3.9 | $3.7 - 3.9 | $4.9 - 5.1 | $4.3 - 4.5
Capital Investments (Data Center Contract) | $1.2 - 1.4 | $1.5 - 1.7 | $1.8- 2.0 | $1.0 - 1.2 | $0.4 - 0.6
Capital Investments (Total) | $5.1 - 5.5 | $5.2 - 5.6 | $5.5 - 5.9 | $5.9 - 6.3 | $4.7 - 5.1

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NiSource Inc.
Regulatory Capital Programs. We continue to upgrade and modernize our electric system to enhance safety and reliability by addressing aged infrastructure and deploying advanced grid technologies. We are also upgrading and modernizing our gas infrastructure to enhance safety and reliability by reducing leaks. An ancillary benefit of these programs is the reduction of GHG emissions. In 2025, we continue to move forward on core infrastructure investment programs supported by complementary regulatory and customer initiatives across five states of our operating area.
The following table describes the most recent vintage of our regulatory programs to recover infrastructure replacement and other federally mandated compliance investments:

(in millions) |  |  |  |  |
Company | Program | Capital Investment | Investment Period | Filing Date | Costs Covered(1) |
Approved |
Columbia of Ohio | IRP - 2025 | $ | 978.7 |  | 4/21-12/24 | 2/27/2025 | Replacement of hazardous service lines, cast iron, wrought iron, uncoated steel, and bare steel pipe. |
Columbia of Ohio | PHMSA IRP - 2025 | $ | 78.2 |  | 1/23-12/24 | 2/28/2025 | Investments necessary to comply with the PHMSA Mega Rule. |
Columbia of Ohio | CEP - 2025 | $ | 1,027.8 |  | 4/21-12/24 | 2/27/2025 | Assets not included in the IRP or PHMSA IRP. |
Columbia of Virginia | SAVE - 2025 | $ | 89.0 |  | 10/24-12/25 | 8/15/2024 | Replacement projects that (1) enhance system safety or reliability, or (2) reduce, or potentially reduce, greenhouse gas emissions. Includes costs associated with Advanced Leak Detection and Repair. |
Columbia of Kentucky | SMRP - 2025 | $ | 128.5 |  | 1/23-12/25 | 10/15/2024 | Replacement of mains and inclusion of system safety investments. |
NIPSCO - Electric(2) | TDSIC - 7 | $ | 315.6 |  | 7/22-3/25 | 5/27/2025 | New or replacement projects undertaken for the purpose of safety, reliability, system modernization or economic development. |
NIPSCO - Electric(3) | GCT - 2 | $ | 80.1 |  | 11/25-4/26 | 6/18/2025 | New gas peaker generation project costs forecasted through April 2026. |
NIPSCO - Gas | TDSIC - 9 | $ | 34.0 |  | 3/24-3/25 | 5/23/2025 | New or replacement projects undertaken for the purpose of safety, reliability, system modernization, or economic development. |
NIPSCO - Gas | FMCA - 4 | $ | 9.4 |  | 6/24-12/24 | 2/25/2025 | Project costs to comply with federal mandates. |
Pending Commission Approval |
NIPSCO - Gas | FMCA - 5 | $ | 21.9 |  | 6/24-6/25 | 8/27/2025 | Project costs to comply with federal mandates. |
Columbia of Virginia | SAVE - 2026 | $ | 176.1 |  | 10/24-12/26 | 8/12/2025 | Replacement projects that (1) enhance system safety or reliability, or (2) reduce, or potentially reduce, greenhouse gas emissions. Includes costs associated with Advanced Leak Detection and Repair. |
Columbia of Kentucky | SMRP - 2026 | $ | 181.4 |  | 1/23-12/26 | 10/15/2025 | Replacement of mains and inclusion of system safety investments. |

(1)Programs do not include any costs already included in base rates.
(2)TDISC – 7 was originally filed on May 27, 2025 and refiled on July 2, 2025, due to the Electric Rate Case Order. The refiling adjusted the capital in the tracker to go down from $744.7 million to $315.6 million.
(3)Capital investment is based on a projected amount. The capital investment has not all been incurred to date and represents a forecasted average for the billing period.
NIPSCO Gas filed an FMCA CPCN on April 21, 2025. The petition is seeking recovery of spend incurred related to certain federally mandated Pipeline Safety IV Compliance Plan costs. The request includes $244.1 million of estimated capital, including indirect costs and AFUDC. An order was received on October 22, 2025 granting the CPCN requested.
Financing Activities
Common Stock. Refer to Note 6, "Equity," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for information on common stock.
Long-Term Debt. Refer to Note 8, "Long-Term Debt," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for information on long-term debt activity.
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NiSource Inc.
Short-Term Debt. Refer to Note 7, "Short-Term Borrowings," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for information on short-term debt activity.
Noncontrolling Interest. Refer to Note 4, "Noncontrolling Interests," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for information on contributions and distributions from noncontrolling interests.
Sources of Liquidity
The following table displays our liquidity position as of September 30, 2025 and December 31, 2024:

(in millions) | September 30, 2025 | December 31, 2024
Current Liquidity |  |
Revolving Credit Facility | $ | 1,850.0 |  | $ | 1,850.0 |
Accounts Receivable Programs(1) | 245.0 |  | 175.0 |
Less: |  |
Commercial Paper | 1,060.0 |  | 604.6 |
Accounts Receivable Programs Utilized | 200.0 |  | — |
Letters of Credit Outstanding Under Credit Facility | 25.0 |  | 9.4 |
Add: |  |
Cash and Cash Equivalents | 95.0 |  | 156.6 |
Net Available Liquidity | $ | 905.0 |  | $ | 1,567.6 |

(1)Represents the lesser of the seasonal limit or maximum borrowings supportable by the underlying receivables.
Debt Covenants. We are subject to a financial covenant under our revolving credit facility, which requires us to maintain a debt to capitalization ratio that does not exceed 70.0%. As of September 30, 2025, the ratio was 54.7%.
Credit Ratings. The credit rating agencies periodically review our ratings, taking into account factors such as our capital structure and earnings profile. The following table includes our and NIPSCO's credit ratings and ratings outlook as of September 30, 2025. There were no changes to the below credit ratings or outlooks since February 2020.
A credit rating is not a recommendation to buy, sell, or hold securities, and may be subject to revision or withdrawal at any time by the assigning rating organization.

| S&P | Moody's | Fitch
| Rating | Outlook | Rating | Outlook | Rating | Outlook
NiSource | BBB+ | Stable | Baa2 | Stable | BBB | Stable
NIPSCO | BBB+ | Stable | Baa1 | Stable | BBB | Stable
Commercial Paper | A-2 | Stable | P-2 | Stable | F2 | Stable

Certain of our subsidiaries have agreements that contain ''ratings triggers'' that require increased collateral if our credit rating or the credit ratings of certain of our subsidiaries are below investment grade. These agreements are primarily for insurance purposes and for the physical purchase or sale of power. As of September 30, 2025, the collateral requirement that would be required in the event of a downgrade below the ratings trigger levels would amount to approximately $141.8 million. In addition to agreements with ratings triggers, there are other agreements that contain ''adequate assurance'' or ''material adverse change'' provisions that could necessitate additional credit support such as letters of credit and cash collateral to transact business.
Equity. Our authorized capital stock consists of 770,000,000 shares, $0.01 par value, 750,000,000 are common stock and 20,000,000 are preferred stock. As of September 30, 2025, 477,136,079 shares of common stock were outstanding and no shares of preferred stock were outstanding.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Contractual Obligations. A summary of contractual obligations is included in the Company's Annual Report on Form 10-K for the year ended December 31, 2024. We will be required to make substantial cash payments under supply and other agreements, including the EPC Contracts, although we may terminate the EPC Contracts for convenience and make associated termination payments if the Data Center Contract is terminated or the underlying assets are not approved by the IURC. The expected payments under the EPC Contracts and other contracts relating to our data center developments and potential future data center developments are included in the estimated amounts set forth in row “Capital Investments (Data Center Contract)” in the table included under “Investing Activities” above. Except for these items and our March and June 2025 debt issuances, there were no additional material changes from year-end during the nine months ended September 30, 2025. Refer to Note 8, "Long-Term Debt," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for additional information regarding the debt issuances. Refer to “Executive Summary - NIPSCO Data Center Contract and Strategy” and Footnote 14, Commitments and Contingencies for additional information regarding the EPC Contracts and equipment supply contracts.
Guarantees, Indemnities and Other Off Balance Sheet Arrangements. We and certain of our subsidiaries enter into various agreements providing financial or performance assurance to third parties on behalf of certain subsidiaries as a part of normal business. Such agreements include guarantees and stand-by letters of credit. Refer to Note 14, "Other Commitments and Contingencies," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for additional information about such arrangements.
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NiSource Inc.
Regulatory, Environmental and Safety Matters
Cost Recovery and Trackers
Comparability of our line item operating results is impacted by regulatory trackers that allow for the recovery in rates of certain costs such as those described below. Increases in the costs that are subject to approved regulatory tracker mechanisms generally lead to increased regulatory assets, which ultimately result in a corresponding increases in operating revenues and expenses and, therefore, have essentially no impact on total operating income results. Certain approved regulatory tracker mechanisms allow for abbreviated regulatory proceedings in order for the operating companies to quickly implement revised rates and recover associated costs.
A portion of the Columbia Operations' and NIPSCO Operations' revenue is related to the recovery of gas costs, the review and recovery of which occurs through standard regulatory proceedings. All states in our operating area require periodic review of actual gas procurement activity to determine prudence and to confirm the recovery of prudently incurred energy commodity costs supplied to customers.
We recognize that energy efficiency reduces emissions, conserves natural resources and saves our customers money. Our gas distribution companies offer programs such as energy efficiency upgrades, home checkups and weatherization services. The increased efficiency of natural gas appliances and improvements in home building codes and standards contributes to a long-term trend of declining average use per customer. While we are looking to expand offerings so the energy efficiency programs can benefit as many customers as possible, our gas distribution operations utilities have pursued changes in rate design to more effectively match recoveries with costs incurred. Columbia of Ohio has adopted a straight fixed variable rate design for residential and small commercial customers that closely links the recovery of fixed costs with fixed charges. Columbia of Maryland and Columbia of Virginia have regulatory approval for weather and revenue normalization adjustments for certain customer classes, which adjust monthly revenues that exceed or fall short of approved levels. Columbia of Pennsylvania continues to operate its pilot residential weather normalization adjustment and also has a fixed customer charge. This weather normalization adjustment only adjusts revenues when actual weather compared to normal varies by more than 3%. Columbia of Kentucky charges certain customer classes a mix of fixed and weather normalized volumetric rates during the peak heating season. NIPSCO Gas and Electric include a fixed customer charge for residential and small commercial and industrial customer classes. NIPSCO Gas has implemented a weather normalization adjustment for certain of its customer classes.
A portion of the NIPSCO Operations' revenue is related to the recovery of fuel costs to generate power and the fuel costs related to purchased power. These costs are recovered through a FAC, which is updated quarterly to reflect actual costs incurred to supply electricity to customers.
While increased efficiency of electric appliances and improvements in home building codes and standards have similarly impacted the average use per electric customer in recent years, NIPSCO expects future growth in per customer usage as a result of increasing electric applications, such as electric vehicles. These ongoing changes in use of electricity will likely lead to development of innovative rate designs, and NIPSCO will continue efforts to design rates that increase the certainty of recovery of fixed costs.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Regulatory, Environmental and Safety Matters
Rate Case Actions
The following table describes current rate case actions as applicable in each of our jurisdictions net of tracker impacts:

(in millions) |  |  |  |
Company | Approved ROE | Requested Incremental Revenue | Approved Incremental Revenue | Filing Date | Rates Effective
Approved Rate Cases |  |  |  |
Columbia of Pennsylvania(1) | None specified | $ | 124.1 |  | $ | 74.0 |  | March 15, 2024 | December 2024
Columbia of Maryland | 9.80 | % | $ | 10.7 |  | $ | 7.8 |  | September 24, 2024 | April 2025
Columbia of Kentucky | 9.75 | % | $ | 23.8 |  | $ | 14.3 |  | May 16, 2024 | January 2025
Columbia of Virginia(2) | 9.75 | % | $ | 37.2 |  | $ | 28.2 |  | April 29, 2024 | October 2024
Columbia of Ohio | 9.60 | % | $ | 221.4 |  | $ | 68.3 |  | June 30, 2021 | March 2023
NIPSCO - Gas(3) | 9.75 | % | $ | 161.9 |  | $ | 120.9 |  | October 25, 2023 | August 2024
NIPSCO - Electric(4) | 9.75 | % | $ | 368.7 |  | $ | 257.0 |  | September 12, 2024 | July 2025
Pending Rate Cases |  |  |  |  |
Columbia of Pennsylvania(5) | In process | $ | 110.5 |  | In process | March 20, 2025 | December 2025

(1)No approved ROE is identified for this matter since the approved revenue increase is the result of a black box settlement under which parties agree upon the amount of increase.
(2)The approved rate case resulted in a black box settlement, representing a settlement to a specific revenue increase but not a specified ROE. The settlement provides use of a 9.75% ROE for future SAVE filings.
(3)New rates were implemented in 2 steps, with implementation of Step 1 rates effective in August 2024 and Step 2 rates effective in February 2025.
(4)New rates were implemented in multiple steps, with implementation of Step 1 rates effective in July 2025 and Step 2 rates effective no later than March 2026.
(5)In October 2025, a Recommended Decision (RD) was issued by the Administrative Law Judges (ALJs) for the PUC to deny the request of Columbia Gas to increase base rates. Alternatively, the ALJs recommended that Columbia Gas be granted a $66.4 million revenue increase, effective for service rendered on and after January 1, 2026. Columbia Gas filed Exceptions to the ALJs’ RD, proposing an increase of at least $74.2 million, effective on and after December 19, 2025. A Final Order from the PUC is expected in the fourth quarter of 2025.
PHMSA Legislation and Regulations
To fulfill our vision of being a trusted energy provider, we follow safety practices required by regulations and we implement our Safety Management System ("SMS"). SMS serves as the framework to identify and reduce risks and ensure consistent safety processes, procedures and operations across the organization.
As directed by law in the Protecting Our Infrastructure of Pipelines and Enhancing Safety (PIPES) Act of 2020, PHMSA has revised, and continues to revise, the pipeline safety regulations focused on public safety and environmental hazard mitigation. The PIPES Act of 2020 specifically includes leak detection and repair criteria (the "LDAR" rule) and regulations that require operators to upgrade their existing low-pressure regulating stations with enhanced safeguards and update distribution integrity management plans, emergency response plans, and operation and maintenance plans (the Safety of Gas Distribution Pipelines, or "SGDP" rule).
In May 2023, PHMSA proposed regulatory revisions under the PIPES Act of 2020 to minimize methane emissions and improve public safety. Under these proposed revisions, our subsidiaries would be required to detect and repair an increased number of gas leaks, reduce the time to repair leaks, increase leak survey, and expand our existing advanced leak detection program. In January 2025, PHMSA withdrew the final LDAR rule and it has not gone into effect.
In September 2023, PHMSA proposed additional regulatory revisions under the PIPES Act of 2020 to enhance distribution system safety through equipment and procedural expectations in the form of the SGDP rule. Operators will be required to incorporate additional protections for low pressure distribution systems that prevent over-pressurization, amend construction procedures designed to minimize the risk of incidents caused by system over-pressurization, and update distribution integrity management programs to cover and prepare for over-pressurization incidents. PHMSA did not progress the SGDP rulemaking in 2024.
We continue to evaluate and monitor PHMSA-related legislation and regulations but cannot predict the impact of changing pipeline safety regulations on our business at this time.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Regulatory, Environmental and Safety Matters
Environmental and Climate Change Issues
On March 12, 2025, the EPA announced it will undertake 31 deregulatory actions to advance the administration’s policy priorities as directed by various executive orders. These actions will address multiple existing water, waste, air and climate regulations including, but not limited to, GHG rules and the Legacy CCR Rule. On July 22, 2025, the EPA proposed a rule that, if finalized, would extend the deadline to submit Part 1 Facility Evaluation Reports from February 2026 to February 2027. On July 29, 2025, the EPA proposed rescinding the 2009 Endangerment Finding, the scientific and legal foundation for federal GHG regulations under the Clean Air Act. NiSource will continue to monitor these matters and assess the impacts to our business as regulations are proposed and finalized, or as otherwise required by law.
Physical Climate Risks. Increased frequency of severe and extreme weather events associated with climate change could materially impact our facilities, energy sales, and results of operations. We are unable to predict these events. However, we perform assessments of physical risk, including physical climate risk, to our business. More extreme and volatile temperatures, increased storm intensity and flooding, and more volatile precipitation leading to changes in lake and river levels are among the weather events that are most likely to impact our business. Efforts to mitigate these physical risks continue to be implemented.
Transition Climate Risks and Opportunities. We actively engage with and monitor the impact that proposed legislative and regulatory programs related to GHG emissions, at both the federal and state levels, would have on our business.
On June 11, 2025, the EPA proposed to repeal GHG emissions standards for fossil fuel-fired power plants that were finalized by the previous federal administration in May 2024. The proposed repeal would eliminate key requirements from the 2024 Carbon Pollution Standards, including capacity factor thresholds and carbon capture and storage (CCS) mandates. If finalized, this action would remove regulatory constraints that could significantly impact NIPSCO’s planned gas generation, allowing customers to avoid approximately $675 million in additional cost as contemplated through the 2024 NIPSCO IRP.
We also continue to monitor evolving state policies related to GHG emissions from our gas distribution companies. The Climate Solutions Now Act of 2022 requires Maryland to reduce GHG emissions by 60% by 2031 (from 2006 levels), and it requires the state to reach net zero emissions by 2045. The Maryland Department of the Environment ("MDE") adopted a plan to achieve its 2031 goal and is required to adopt a plan for their 2045 net zero goal by 2030. The Act also enacts a state policy to move to broader electrification of both existing buildings and new construction. In December 2024, the MDE issued final Building Energy Performance Standards, which would require net zero direct GHG emissions from large buildings by 2040 with interim targets, or payments of an alternative compliance fee. Under an executive order, Maryland is also developing a Clean Heat Standard and a Zero-Emission Heating Equipment Standard that are intended to transition gas appliances to electric heat pumps. In June 2025, the Public Service Commission ("PSC") issued an order directing its Staff to prepare proposed regulations by December 2025, eliminating Company contributions to main or service extensions to new residential and commercial customers. In August 2025, the PSC instituted formal proceedings to investigate issues pertaining to long-term natural gas company planning practices. One purpose of the proceedings is to ensure that planning is consistent with Maryland's climate goals. Columbia of Maryland cannot predict the final impact of these policies on our business at this time.
Net Zero Goal. In November 2022, we announced a goal of net zero GHG emissions by 2040 covering both Scope 1 and Scope 2 GHG emissions ("Net Zero Goal"). Our Net Zero Goal builds on GHG emission reductions achieved to-date. We plan to achieve our Net Zero Goal primarily through continuation and enhancement of existing programs, such as retiring and replacing coal-fired electric generation with low- or zero-emission electric generation, ongoing pipe replacement and modernization programs, and deployment of advanced leak-detection technologies. In addition, we plan to advance other low- and zero-emission energy resources and technologies, which may include hydrogen, renewable natural gas, long-duration storage, and/or deployment of carbon capture and utilization technologies, if and when these become technologically and economically feasible. Carbon offsets and renewable energy credits may also be used to support achievement of our Net Zero Goal. As of the end of 2024, we had reduced Scope 1 GHG emissions by approximately 72% from 2005 levels.
Our GHG emissions projections, including achieving a Net Zero Goal, are subject to various assumptions that involve risks and uncertainties, and did not include any assumptions related to data center development and associated load growth. We remain committed to our Net Zero Goal, however, certain of our interim goals may evolve as we assess and respond to business opportunities such as data centers. Achievement of our Net Zero Goal by 2040 will require supportive regulatory and legislative policies, favorable stakeholder environments and advancement of technologies that are not currently economically or
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Regulatory, Environmental and Safety Matters
technologically feasible to deploy at scale, as well as execution of our business plan. Otherwise, our actual results or ability to achieve our Net Zero Goal, including by 2040, may differ materially.
Market Risk Disclosures
Risk is an inherent part of our businesses. The extent to which we properly and effectively identify, assess, monitor and manage each of the various types of risk involved in our businesses is critical to our profitability. We seek to identify, assess, monitor and manage, in accordance with defined policies and procedures, the following principal market risks that are involved in our businesses: commodity price risk, interest rate risk and credit risk. We manage risk through a multi-faceted process with oversight by the Risk Management Committee that requires constant communication, judgment and knowledge of specialized products and markets. Our senior management takes an active role in the risk management process and has developed policies and procedures that require specific administrative and business functions to assist in the identification, assessment and control of various risks. These may include, but are not limited to market, operational, financial, compliance and strategic risk types. In recognition of the increasingly varied and complex nature of the energy business, our risk management process, policies and procedures continue to evolve and are subject to ongoing review and modification.
Commodity Price Risk
Our gas and electric subsidiaries have commodity price risk primarily related to the purchases of natural gas and power. To manage this market risk, our subsidiaries use derivatives, including commodity futures contracts, swaps, forwards and options. We do not participate in speculative energy trading activity.
Commodity price risk resulting from derivative activities at our rate-regulated subsidiaries is limited and does not bear significant exposure to earnings risk, since our current regulatory mechanisms allow recovery of prudently incurred purchased power, fuel and gas costs through the rate-making process, including gains or losses on these derivative instruments. These changes are included in the GCA and FAC regulatory rate-recovery mechanisms. If these mechanisms were to be adjusted or eliminated, these subsidiaries may begin providing services without the benefit of the traditional rate-making process and may be more exposed to commodity price risk. For additional information, see "Results and Discussion of Segment Operations" in this Management's Discussion.
Our subsidiaries are required to make cash margin deposits with their brokers to cover actual and potential losses in the value of outstanding exchange traded derivative contracts. The amount of these deposits, some of which are reflected in our restricted cash balance, may fluctuate significantly during periods of high volatility in the energy commodity markets.
Refer to Note 10, "Risk Management Activities," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for further information on our commodity price risk assets and liabilities.
Interest Rate Risk
We are exposed to interest rate risk as a result of changes in interest rates on borrowings under our revolving credit agreement, commercial paper program, and accounts receivable programs, which have interest rates that are indexed to short-term market interest rates. Based upon average borrowings and debt obligations subject to fluctuations in short-term market interest rates, an increase (or decrease) in short-term interest rates of 100 basis points (1%) would have increased (or decreased) interest expense by $1.8 million and $6.1 million for the three and nine months ended September 30, 2025 and $1.7 million and $6.9 million for the three and nine months ended September 30, 2024, respectively. We are also exposed to interest rate risk as a result of changes in benchmark rates that can influence the interest rates of future long-term debt issuances. From time to time we may enter into forward interest rate instruments to lock in long term interest costs and/ or rates.
Credit Risk
Due to the nature of the industry, credit risk is embedded in many of our business activities. Our extension of credit is governed by a Corporate Credit Risk Management Policy which establishes guidelines for documenting management approval levels for credit limits, evaluating creditworthiness, and credit risk mitigation efforts. Exposures to credit risks are monitored by the risk management function, which is independent of commercial operations. Credit risk arises due to the possibility that a customer, supplier or counterparty will not be able or willing to fulfill its obligations on a transaction on or before the settlement date. For derivative-related contracts, credit risk arises when counterparties are obligated to deliver or purchase defined commodity units of gas or power to us at a future date per execution of contractual terms and conditions. Exposure to credit risk is measured in
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
terms of both current obligations and the market value of forward positions net of any posted collateral such as cash and letters of credit.
The financial status of our banking partners is periodically assessed through traditional credit ratings provided by major credit rating agencies.
Other Information
Critical Accounting Estimates
A summary of our critical accounting estimates is included in the Company's Annual Report on Form 10-K for the year ended December 31, 2024. There were no material changes made as of September 30, 2025.
Recently Issued Accounting Pronouncements
Refer to Note 2, "Recent Accounting Pronouncements," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for additional information about recently issued and adopted accounting pronouncements.
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NiSource Inc.
ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
Quantitative and qualitative disclosures about market risk are reported in Item 2, "Management's Discussion and Analysis of Financial Condition and Results of Operations - Market Risk Disclosures."
ITEM 4. CONTROLS AND PROCEDURES
Evaluation of Disclosure Controls and Procedures
Our chief executive officer and our chief financial officer are responsible for evaluating the effectiveness of our disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)). Our disclosure controls and procedures are designed to provide reasonable assurance that the information required to be disclosed by us in reports that we file or submit under the Exchange Act is accumulated and communicated to our management, including our chief executive officer and chief financial officer, as appropriate, to allow timely decisions regarding required disclosure and is recorded, processed, summarized and reported within the time periods specified in the rules and forms of the SEC. Based upon that evaluation, our chief executive officer and chief financial officer concluded that, as of the end of the period covered by this report, our disclosure controls and procedures were effective at a reasonable assurance level.
Changes in Internal Controls
During the third quarter, we implemented the second and third phases of our three-phased Enterprise Asset Management ERP program. This implementation reflects our ongoing commitment to streamlining operations and enhancing logistics across the company. While there are inherent risks involved with the implementation of new systems and changes in internal controls associated with the transition to the new system, management believes it is adequately monitoring and managing the transition. Apart from this ERP implementation, there have been no changes in our internal control over financial reporting that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting during the most recently completed quarter covered by this report.
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NiSource Inc.
PART II
ITEM 1. LEGAL PROCEEDINGS
For a description of our legal proceedings, see Note 14, "Other Commitments and Contingencies - B. Legal Proceedings," in the Notes to the Condensed Consolidated Financial Statements (unaudited).
ITEM 1A. RISK FACTORS
Please refer to the risk factors set forth in Part I, Item 1A of the Annual Report on Form 10-K for the year ended December 31, 2024 and Part II, Item 1A of the Quarterly Report on Form 10-Q for the quarter ended June 30, 2025. There have been no material changes to such risk factors other than as set forth below.
Our construction of the Contract Assets involves significant risks. Construction delays, cost overruns or performance issues with the Contract Assets could reduce our returns under the Data Center Contract and could require us to obtain additional financing. Any further development of generation and transmission assets in connection with future data center contracts is expected to be subject to similar risks.
We expect to construct, through GenCo, 400 MW of new battery storage and a new power generation facility consisting of two 1,300 MW combined-cycle, natural gas-fired turbines, which are expected to reach commercial operation between 2028 and 2032, as well as related transmission and distribution assets (which will be constructed by NIPSCO). In addition, in order to perform under any further data center contracts, we expect that we will need to develop additional generation and transmission assets. Our return under the Data Center Contract will be, and our return under future data center contract is expected to be, affected by our ability to construct, develop and place into service these assets on time or at all and consistent with initial cost estimates, as well as the performance of these assets once constructed and placed into service.
We have not previously constructed generation assets of the type and scale contemplated by the Data Center Contract. Although we have engaged reputable EPC contractors to manage the construction of these new assets, our ability to complete the construction in a timely manner and within budget is contingent upon many variables and subject to substantial risks. These variables include, but are not limited to, the receipt, timing and terms of required regulatory approvals, including approvals from the IURC and FERC; the ability of key suppliers and contractors to timely satisfy their obligations under existing or future contracts and in compliance with the terms of such contracts, including the EPC Contracts and equipment supply contracts we have already entered into; the impact of new tariffs, if any, inflation and other trade or economic factors that may impact the cost of supplies and services; changes in law or regulation, including environmental compliance requirements; the availability of and ability of our contractors to hire and retain qualified labor and the cost of such labor; the impact of public health emergencies or natural disasters or other severe weather events; capital market conditions, including the availability of credit and our ability to obtain financing on acceptable terms (as discussed below); charges allocated to us by MISO with respect to these assets; and the impact of public involvement, intervention or litigation. In addition, our ability to complete construction of any additional generation and transmission assets developed to support future data center contracts will be subject to all or most of the foregoing risks.
Under the Data Center Contract, if the Contract Assets are delivered into service late or do not achieve certain other performance-related milestones, Customer is entitled to liquidated damages, which would be offset against NIPSCO’s billings to Customer and reduce the rate of return earned under the Data Center Contract. In addition, our actual costs to construct the Contract Assets may exceed the budget contemplated by the Data Center Contract, which could result from delays in construction or from other factors. Any such cost overruns will need to be funded initially by us, either through our cash flows from operating activities or additional debt or equity financing. Although our EPC contracts provide certain protections against cost overruns under those contracts, and any excess costs not recoverable through the EPC contracts are to be shared by us and Customer, any recoveries from our EPC contractors and/or Customer would occur over an extended period of time. The need for us to fund these expenses in the first instance may reduce our ability to use our operating cash flows for other purposes or may require us to obtain additional debt or equity financing, which may not be available on favorable terms or at all. These costs, if incurred, could negatively impact our return under the Data Center Contract or adversely affect our future results and financial condition. In addition, we expect that construction delays, performance shortfalls or cost overruns in connection with construction of generation and transmission assets supporting any future data center contracts could similarly have a negative effect on our return under such contracts and our financial condition.
We will be required to obtain significant additional financing in order to construct the Contract Assets and any generation or transmission assets we develop to support future data center contracts. Such financing may not be available on favorable terms, if at all.
In order to finance the construction of the Contract Assets, as well as any generation and transmission assets we develop to support future data center contracts, we expect to incur significant additional long-term debt and issue additional equity in NiSource, in addition to the financing we otherwise would seek to support investments in our existing businesses and refinance
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ITEM 1A. RISK FACTORS
NiSource Inc.
existing indebtedness. The LLC Agreement and Amended LLC Agreement will allow for additional capital contributions from affiliates of Blackstone to NIPSCO Holdings II and Generation Holdings II in connection with such Blackstone affiliates’ minority interest investments in those entities. In addition, we may consider other funding sources, structures, or partnerships as market conditions and strategic considerations evolve. The amount of additional long-term debt or NiSource equity needed to support construction of the Contract Assets and any generation and transmission assets to support future data center contracts could increase, potentially significantly, from our current expectations if we experience construction delays or cost overruns.
External factors such as inflation, monetary policy or other market conditions could impact our cost of borrowing and could make it more difficult to obtain the financing that is required to construct the Contract Assets on favorable terms, or at all. The issuance of additional debt could negatively impact our credit ratings and overall cost of capital, which could in turn adversely affect our future results and liquidity. In addition, an economic downturn or uncertainty, market turmoil, changes in interest rates, changes in tax policy, challenges faced by financial institutions, or a change in investor sentiment toward us or the utilities industry or the cloud-computing, artificial intelligence and data center industry generally could adversely affect our ability to raise the necessary capital. Reduced access to capital markets, increased borrowing costs, and/or lower equity valuation levels could jeopardize our ability to complete construction of the Contract Assets on-time and within budget, and could reduce future earnings per share and cash flows. In addition, any rise in interest rates may lead to higher borrowing costs, which may adversely impact reported earnings, cost of capital and capital holdings.
Pursuit of our partnership with Customer creates significant opportunity costs and reduces our strategic and financial flexibility in the near term.
We expect to incur significant indebtedness to fund our construction of the Contract Assets. Doing so will reduce our ability to incur further indebtedness to pursue other strategic opportunities, such as partnerships with other large data center customers or strategic mergers and acquisitions, while at the same time maintaining our investment grade credit ratings, which may require us to rely to a greater degree on equity financing in connection with future data center contracts and also may increase our reliance on equity financing for future investments in our existing traditionally regulated utility business, each of which could lead to substantial dilution of our existing shareholders. In addition, our credit rating agencies consider the percentage of our business comprised of traditionally regulated utility operations in their analysis of our credit quality.
In addition to these factors relating to our financing and credit ratings, our partnership with Customer is expected to employ a significant amount of our existing excess transmission infrastructure, which will limit our ability to use these assets for other opportunities, including additional data center opportunities. Furthermore, effectively overseeing the construction and financing of the Contract Assets will require significant time and attention of our management, which could detract from their oversight of our existing business and ability to pursue other strategic opportunities.
The return structure and risk profile of Data Center Contract and related development of the Contract Assets differ from those of NIPSCO’s traditionally regulated utility operations. Any future data center contracts we enter into are expected to have a comparable structure and risk profile.
NIPSCO’s and GenCo’s operations under the Data Center Contract will be, and under future data center contracts are expected to be, regulated by the IURC in a different way from the regulatory mechanisms applicable to NIPSCO’s historical operations, which could affect the manner in which we recover our investment costs and earn a return on our investment. NIPSCO’s electric utility rates historically have been determined and approved in regulatory proceedings with the IURC based on an analysis of NIPSCO’s costs to provide utility service and a return on, and recovery of, NIPSCO’s investment in the utility business. Through the IURC rate-making process, retail rates may be adjusted over time, and NIPSCO may request additional revenue, in order to cover ongoing costs and investment and earn an adequate return.
In contrast, the terms of the Data Center Contract were, and the terms of any future data center contracts will be, determined by commercial negotiation with Customer. In the case of the Data Center Contract, these terms include the charges that we receive from Customer, which are designed to allow us to recover the costs that we incur to construct and operate the Contract Assets and earn a return, and provisions that may result in adjustments to those charges such as, among other factors, those relating to certain liquidated damages that we may owe Customer in the event of construction delays or capacity shortfalls and the parties’ responsibility to share cost overruns, among other provisions. These terms do not guarantee a specific overall rate of return, and the overall return we earn under the Data Center Contract may ultimately be lower than that of NIPSCO’s traditional utility operations. The IURC will not regulate the commercial terms of the Data Center Contract and is not expected to regulate the commercial terms of any future data center contracts; however, the IURC is expected to maintain oversight under the Data Center Contract and any future data center contracts to ensure NIPSCO provides reliable service to Customer and any future data center customers at just and reasonable rates. In order to recover our investment costs and earn our return under the Data Center Contract and any future data center contracts, our subsidiaries must efficiently perform their own obligations and must look to the Customer or future customers (or, if applicable, any parent guarantor) to perform its obligations, rather than the IURC making use of its traditional rate-making process. In addition, under the Data Center Contract, NIPSCO has direct contractual obligations to the Customer to, among other things, construct the Contract Assets and deliver committed electric
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NiSource Inc.
capacity in fixed amounts by certain dates. We expect our subsidiaries to have similar contractual obligations to customers in connection with any future data center contracts. If disputes arise with data center customers, including the Customer, regarding provisions of a data center contract, including the Data Center Contract, or payments to be made or actions to be taken thereunder, we may be significantly disadvantaged as a result of, among other factors, the significance of such contracts to us and the greater resources (financial and otherwise) available to the relevant customer. Any dispute or litigation with a data center customer, including the Customer, could create significant demands on the attention of management and result in significant costs to us.
In addition, the IURC, through its review and approval of the Data Center Contract and PPA between NIPSCO and GenCo, will have ultimate authority over the implementation of these agreements. In this context, we will need to continuously assess the applicability of ASC Topic 980 over the life of the Data Center Contract. It is possible that significant construction overruns, capacity shortfalls or other events that could result in NIPSCO or GenCo owing liquidated damages could either preclude ongoing application of ASC Topic 980 or result in an immediate disallowance and impairment of the Contract Assets. In addition, early termination of the Data Center Contract, could result in such impairment and discontinuation of application of ASC Topic 980, unless the Contract Assets can be used to support new or existing customers. If we incur significant costs that we are not able to recover from Customer (for example, greater than expected purchases of market capacity or operations and maintenance costs significantly exceeding those contemplated by the Data Center Contract), this also could discontinue the application of ASC Topic 980 to the Data Center Contract and the Contract Assets. We expect any future data center contracts will be subject to comparable risks.
Our partnership with Customer exposes us to significant customer concentration risk.
Customer will be a significant customer of our electric utility operations. For example, the generating capacity of the Contract Assets, when fully delivered into service, is expected to be approximately equivalent to the generating capacity of all NIPSCO’s existing generating assets. However, Customer has the right to terminate the Data Center Contract for convenience following certain notice periods. If Customer terminates or defaults under the Data Center Contract or elects not to renew the Data Center Contract after the initial term, we may not be able to replace Customer’s demand or otherwise fully utilize the assets constructed in connection with the Data Center Contract. We also may not receive the same level of return with respect to any alternative use.
In addition, Customer has a one-time option (exercisable no later than March 31, 2029) to halve committed capacity under the Data Center Contract to 1,200 MW commencing January 31, 2032. If Customer elects to reduce the committed capacity under the Data Center Contract or to terminate the Data Center Contract during its initial term, we will not receive the full earnings we expect to receive over the life of the Data Center Contract. Although the Data Center Contract provides for reimbursement for our investment in the Contract Assets and related expenses in the event of a reduction in the committed capacity or early termination, the amount of any reimbursement is capped under the Data Center Contract, with the amount of the caps being based on cost estimates determined as of signing. Furthermore, our ability to collect any reimbursable amounts will depend upon the willingness and ability of the Customer or its parent guarantor to satisfy their payment obligations under the Data Center Contract and related guarantee. Accordingly, we may not be able to recover our full investment, which may adversely affect our future results and financial condition.
Any of the above outcomes could adversely affect our future results, financial conditions and results of operations. Termination of the Data Center Contract during its initial term or exercise by Customer of its one-time option to reduce capacity also may cause us reputational harm, which could, among other things, negatively affect our ability to source and execute contracts with additional data center customers.
Many factors, including those outside our and Customer’s control, could cause Customer to exercise its one-time option to reduce the committee capacity under the Data Center Contract or terminate the Data Center Contract during the initial term. Such factors include, for example: (i) construction delays, cost overruns or capacity shortfalls that occur in connection with our construction of the Contract Assets, (ii) similar problems that Customer may encounter in connection with constructing its data centers, (iii) any decrease or lessening of current cloud-computing or artificial intelligence demand trends or a change in the current supportive legal and regulatory environment (in Northern Indiana or elsewhere) with respect to cloud-computing or artificial intelligence, as well as other factors, which could negatively impact the demand for data centers, (iv) technological or other advances impacting the design and operation of data centers, which could reduce the amount of electricity needed to power data centers and (v) competing energy technologies could become a preferred source of energy for powering data centers.
Any future data center contracts our subsidiaries enter into may contain termination and/or capacity reduction provisions and related reimbursement comparable to the Data Center Contract, exposing us to risks comparable to those described above (the significance of which will be affected by the relative size of any such contract and the costs we incur to develop resources supporting such contract).
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ITEM 1A. RISK FACTORS
NiSource Inc.
In addition, as a result of the Data Center Contract, and any further agreements we may sign with data center companies, our stock price may experience increased volatility as a result of factors outside our control. For example, our stock price may be negatively affected as a result of any actual or perceived slowdown in the adoption of artificial intelligence technology, the regulation or proposed regulation of such technology, or actual or perceived changes in the strategic or financial position of our data center customers.
The long-term MISO capacity accreditation of capacity resources is uncertain. If the capacity resources that we construct to serve Customer or any future data center customers lose accreditation, we would need to construct additional generation assets to fulfill our obligations to such customers.
In recent years, MISO has implemented new capacity accreditation rules and continues to put forth new plans and proposals relating to its accreditation requirements. Recent MISO accreditation changes have affected both natural gas and battery storage generation resources, but battery storage has been more significantly impacted. It is possible that, under future MISO rules, the capacity accreditation for the capacity resources we construct to serve Customer will be eliminated or reduced, in which case we would need to replace or supplement the accredited generation capacity we are planning to build in order to fulfill our obligations to Customer under the Data Center Contract. This additional investment would be funded initially by us. Although under the terms of the Data Center Contract the costs of this additional investment would be shared by us and Customer, our recovery from Customer would occur over an extended period of time. We expect that we would need to obtain significant additional debt and equity financing to fund these investments, which may not be available on favorable terms or at all. These costs, if incurred, could negatively impact our return under the Data Center Contract or adversely affect our future results and financial condition. In addition, these activities would be subject to the construction and financing-related risks described above. Any generation assets we develop to support future data center contracts will be subject to similar risks relating to MISO accreditation, which, depending on the terms of our future data center contracts, may expose us to risks similar to those described above or additional risks.
ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS
None.
ITEM 3. DEFAULTS UPON SENIOR SECURITIES
None.
ITEM 4. MINE SAFETY DISCLOSURES
Not applicable.
ITEM 5. OTHER INFORMATION
Minority Equity Interest Sale
On October 28, 2025, NiSource issued a 19.9% indirect equity interest in NiSource’s wholly-owned subsidiary GenCo to BIP Orion Holdco L.P. and BIP Orion Holdco II L.P., affiliates of Blackstone (collectively, “Investor”), in exchange for $35.2 million. On October 28, 2025, simultaneously with issuance of the 19.9% indirect equity interest in GenCo, Investor, Generation Holdings I, Generation Holdings II and NiSource entered into an Amended and Restated Limited Liability Company Agreement of Generation Holdings II (the “LLC Agreement”).
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The LLC Agreement establishes, among other things, governance rights, exit rights, requirements for additional capital contributions, mechanics for distributions, and other arrangements for Generation Holdings II. Specifically, under the terms of the LLC Agreement, Investor will provide up to $1.325 billion in additional capital contributions over a seven-year period, which obligation is backed by an Equity Commitment Letter from Blackstone or an affiliate thereof. Under the LLC Agreement, Investor is entitled to appoint two directors to the board of directors of Generation Holdings II (the “Board”) so long as Investor (together with any approved affiliate) holds at least a 17.5% Percentage Interest (as defined in the LLC Agreement). Investor is expected to appoint two directors to the Board, such that the Board will be comprised of seven directors, two appointed by Investor and five appointed by NiSource. The LLC Agreement also contains certain investor protections, including, among other things, requiring Investor approval for Generation Holdings II to take certain major actions. In addition, the LLC Agreement contains certain terms surrounding transfer rights and other obligations applicable to both Investor and NiSource. Under the LLC Agreement, Generation Holdings II has agreed that, so long as Investor holds a 14.9% or greater Percentage Interest in Generation Holdings II, Generation Holdings II, NIPSCO Holdings II (as defined below) and/or their respective subsidiaries will be the exclusive vehicles for all power, storage and generation requirements for data center customers within NIPSCO’s service territory.
On October 28, 2025, the members of NIPSCO Holdings II entered into a Third Amended and Restated Limited Liability Company Agreement of NIPSCO Holdings II (the "Amended LLC Agreement"), which, among other changes, increased the amount and time period for additional mandatory capital contributions required to be contributed by Investor by $175 million and seven years, which obligation is backed by an Equity Commitment Letter from Blackstone or an affiliate thereof, and amended certain provisions to facilitate NIPSCO Holdings II and its subsidiaries’ provision of electric service to data center customers (and related activities) and their related contracts and arrangements with Generation Holdings II and its subsidiaries.
The foregoing descriptions of the LLC Agreement and the Amended LLC Agreement do not purport to be complete and are qualified in their entirety by reference to the terms and conditions of the LLC Agreement and Amended LLC Agreement, which are filed as Exhibits 10.1 and 10.2, respectively, and are incorporated by reference herein.
Director and Officer Trading Arrangements
During the quarter ended September 30, 2025, none of our directors or executive officers adopted or terminated a Rule 10b5-1 trading plan or adopted or terminated a non-Rule 10b5-1 trading arrangement (as defined in Item 408(c) of Regulation S-K).
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ITEM 6. EXHIBITS
NiSource Inc.

(10.1) | A mended and Restated Liability Com pany Agreement of Generation Holdings II LLC, dated October 28, 2025.* **
(10.2) | T hird Amended a nd Restated Liability Company Agreement of NIPSCO Holdings II LLC, dated October 28, 2025* **
(31.1) | Certification of Chief Executive Officer pursuant to Rule 13a-14(a)/15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.*
(31.2) | Certification of Chief Financial Officer pursuant to Rule 13a-14(a)/15d-14(a), as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.*
(32.1) | Certification of Chief Executive Officer pursuant to 18. U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (furnished herewith).*
(32.2) | Certification of Chief Financial Officer pursuant to 18. U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (furnished herewith).*
(101.INS) | Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.
(101.SCH) | Inline XBRL Schema Document
(101.CAL) | Inline XBRL Calculation Linkbase Document
(101.LAB) | Inline XBRL Labels Linkbase Document
(101.PRE) | Inline XBRL Presentation Linkbase Document
(101.DEF) | Inline XBRL Definition Linkbase Document
(104) | Cover page Interactive Data File (formatted as inline XBRL, and contained in Exhibit 101.)
* | Exhibit filed herewith.
** | Schedules and similar attachments to this Exhibit have been omitted pursuant to Item 601(a)(5) of Regulation S-K. The Company agrees to furnish supplementally a copy of any omitted schedule or exhibit to the U.S. Securities and Exchange Commission (the “SEC”) upon request

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SIGNATURE
NiSource Inc.
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

|  |  | NiSource Inc. |
|  |  | (Registrant)
Date: | October 29, 2025 | By: | /s/ Gunnar J. Gode
|  |  | Gunnar J. Gode
|  |  | Senior Vice President, Chief Accounting and Tax Officer (Principal Accounting Officer)

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