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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 March 31, 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: 470,702,914 shares outstanding at April 30, 2025.

NISOURCE INC.
FORM 10-Q QUARTERLY REPORT
FOR THE QUARTER ENDED MARCH 31, 2025
Table of Contents

|  |  | Page
| Defined Terms | 3
PART I | FINANCIAL INFORMATION |
| Item 1. | Financial Statements - unaudited |
|  | Condensed Statements of Consolidated Income (unaudited) | 8
|  | Condensed Statements of Consolidated Comprehensive Income (unaudited) | 9
|  | Condensed Consolidated Balance Sheets (unaudited) | 10
|  | Condensed Statements of Consolidated Cash Flows (unaudited) | 12
|  | Condensed Statements of Consolidated Equity (unaudited) | 13
|  | Notes to Condensed Consolidated Financial Statements (unaudited) | 15
| Item 2. | Management’s Discussion and Analysis of Financial Condition and Results of Operations | 35
| Item 3. | Quantitative and Qualitative Disclosures About Market Risk | 57
| Item 4. | Controls and Procedures | 57
PART II | OTHER INFORMATION |
| Item 1. | Legal Proceedings | 58
| Item 1A. | Risk Factors | 58
| Item 2. | Unregistered Sales of Equity Securities and Use of Proceeds | 58
| Item 3. | Defaults Upon Senior Securities | 58
| Item 4. | Mine Safety Disclosures | 58
| Item 5. | Other Information | 58
| Item 6. | Exhibits | 59
| Signature | 60

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. |
NIPSCO | Northern Indiana Public Service Company LLC |
NIPSCO Holdings I | NIPSCO Holdings I LLC |
NIPSCO Holdings II | NIPSCO Holdings II LLC |
NIPSCO Generation | NIPSCO Generation 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 |
Dunns Bridge II | Dunn's Bridge II Solar Generation LLC |
Gibson | Gibson Solar Generation LLC |
Fairbanks | Fairbanks Solar Generation LLC |
Cavalry | Cavalry Solar Generation LLC |
Templeton | Templeton Wind Energy Center LLC |
Abbreviations and Other |  |
AFUDC | Allowance for funds used during construction |
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 |
Blackstone | Blackstone Infrastructure Partners L.P |
BTA | Build-transfer agreement |
CCRs | Coal Combustion Residuals |
CEP | Ohio Capital Expenditure Program |
CERCLA | Comprehensive Environmental Response Compensation and Liability Act (also known as Superfund) |
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 |
DSIC | Distribution System Improvement Charge |
DSM | Demand Side Management |

3

DEFINED TERMS |
EPA | United States Environmental Protection Agency |
EPS | Earnings per share |
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 |
GHG | Greenhouse gases |
GWh | Gigawatt hours |
IRA | Inflation Reduction Act of 2022 |
IRP | Ohio Infrastructure Replacement Program |
IURC | Indiana Utility Regulatory Commission |
JV | Joint Venture |
LIFO | Last In, First Out |
LIHEAP | Low Income Heating Energy Assistance Program |
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 |
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 |

4

DEFINED TERMS |
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 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;
5

•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 Item 1, "Business," Item 1A, "Risk Factors" section of our Annual Report on Form 10-K for the fiscal year ended December 31, 2024, and Part I, Item 2, "Management’s Discussion and Analysis of Financial Condition and Results of Operations," of this report, some of which risks are beyond our control.
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
6

Index | Page
Condensed Statements of Consolidated Income (unaudited) | 8
Condensed Statements of Consolidated Comprehensive Income (unaudited) | 9
Condensed Consolidated Balance Sheets (unaudited) | 10
Condensed Statements of Consolidated Cash Flows (unaudited) | 12
Condensed Statements of Consolidated Equity (unaudited) | 13
Notes to Condensed Consolidated Financial Statements (unaudited) | 15
1. Basis of Accounting Presentation | 15
2. Recent Accounting Pronouncements | 15
3. Revenue Recognition | 16
4. Noncontrolling Interests | 19
5. Earnings Per Share | 20
6. Equity | 21
7. Short-Term Borrowings | 22
8. Long-Term Debt | 22
9. Regulatory Matters | 23
10. Risk Management Activities | 23
11. Fair Value | 25
12. Income Taxes | 28
13. Pension and Other Postemployment Benefits | 28
14. Other Commitments and Contingencies | 28
15. Accumulated Other Comprehensive Loss | 31
16. Business Segment Information | 31
17. Other, Net | 33
18. Supplemental Disclosures of Cash Flow Information | 34

7

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

| Three Months Ended March 31, |  |
(in millions, except per share amounts) | 2025 |  | 2024 |  |  |  |
Operating Revenues |  |  |  |  |  |
Customer revenues | $ | 2,149.5 |  |  | $ | 1,643.0 |  |  |  |  |
Other revenues | 33.7 |  |  | 63.3 |  |  |  |  |
Total Operating Revenues | 2,183.2 |  |  | 1,706.3 |  |  |  |  |
Operating Expenses |  |  |  |  |  |  |
Cost of energy | 647.5 |  |  | 425.0 |  |  |  |  |
Operation and maintenance | 427.8 |  |  | 378.4 |  |  |  |  |
Depreciation and amortization | 258.6 |  |  | 242.1 |  |  |  |  |
Loss on impairment of assets | 0.3 |  |  | — |  |  |  |  |
Other taxes | 89.6 |  |  | 77.4 |  |  |  |  |
Total Operating Expenses | 1,423.8 |  |  | 1,122.9 |  |  |  |  |
Operating Income | 759.4 |  |  | 583.4 |  |  |  |  |
Other Income (Deductions) |  |  |  |  |  |  |
Interest expense, net | (132.8) |  |  | (116.3) |  |  |  |  |
Other, net | 5.8 |  |  | 9.2 |  |  |  |  |
Total Other Deductions, Net | (127.0) |  |  | (107.1) |  |  |  |  |
Income before Income Taxes | 632.4 |  |  | 476.3 |  |  |  |  |
Income Taxes | 105.7 |  |  | 76.0 |  |  |  |  |
Net Income | 526.7 |  |  | 400.3 |  |  |  |  |
Net income attributable to noncontrolling interest | 51.9 |  |  | 35.3 |  |  |  |  |
Net Income Attributable to NiSource | 474.8 |  |  | 365.0 |  |  |  |  |
Preferred dividends | — |  |  | (6.7) |  |  |  |  |
Preferred redemption premium | — |  |  | (14.0) |  |  |  |  |
Net Income Available to Common Shareholders | $ | 474.8 |  |  | $ | 344.3 |  |  |  |  |
Earnings Per Share |  |  |  |  |  |  |
Basic Earnings Per Share | $ | 1.01 |  |  | $ | 0.77 |  |  |  |  |
Diluted Earnings Per Share | $ | 1.00 |  |  | $ | 0.77 |  |  |  |  |
Basic Average Common Shares Outstanding | 470.4 |  |  | 447.9 |  |  |  |  |
Diluted Average Common Shares | 472.5 |  |  | 449.4 |  |  |  |  |

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
8

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

| Three Months Ended March 31, |  |
(in millions, net of taxes) | 2025 |  | 2024 |  |  |  |
Net Income | $ | 526.7 |  |  | $ | 400.3 |  |  |  |  |
Other comprehensive income: |  |  |  |  |  |  |
Net unrealized gain (loss) on available-for-sale debt securities(1) | 0.8 |  |  | (0.3) |  |  |  |  |
Reclassification adjustment for cash flow hedges | (0.1) |  |  | (0.1) |  |  |  |  |
Unrecognized pension and OPEB benefit(2) | 0.5 |  |  | 0.2 |  |  |  |  |
Total other comprehensive income (loss) | 1.2 |  |  | (0.2) |  |  |  |  |
Comprehensive Income | $ | 527.9 |  |  | $ | 400.1 |  |  |  |  |

(1)Net unrealized gain (loss) on available-for-sale debt securities, net of $0.2 million tax expense and $0.1 million tax benefit in the first quarter of 2025 and 2024, respectively.
(2)Unrecognized pension and OPEB benefit, net of $0.1 million of tax expense and $0.1 million tax expense in the first quarter of 2025 and 2024, respectively.
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 Consolidated Balance Sheets (unaudited)

(in millions) | March 31, 2025 |  | December 31, 2024
ASSETS |  |  |
Property, Plant and Equipment |  |  |
Plant | $ | 35,312.5 |  |  | $ | 34,152.9 |
Accumulated depreciation and amortization | (8,822.6) |  |  | (8,699.0) |
Net Property, Plant and Equipment(1) | 26,489.9 |  |  | 25,453.9 |
Investments and Other Assets |  |  |
Unconsolidated affiliates | 6.8 |  |  | 6.5 |
Available-for-sale debt securities (amortized cost of $85.5 and $91.9, allowance for credit losses of $0.2 and $0.1, respectively) | 81.2 |  |  | 86.7 |
Other investments | 84.6 |  |  | 85.5 |
Total Investments and Other Assets | 172.6 |  |  | 178.7 |
Current Assets |  |  |
Cash and cash equivalents | 259.4 |  |  | 156.6 |
Restricted cash | 44.3 |  |  | 42.0 |
Accounts receivable | 1,135.3 |  |  | 987.9 |
Allowance for credit losses | (29.6) |  |  | (23.7) |
Accounts receivable, net | 1,105.7 |  |  | 964.2 |
Gas storage | 42.8 |  |  | 179.6 |
Materials and supplies, at average cost | 183.0 |  |  | 173.3 |
Electric production fuel, at average cost | 35.5 |  |  | 36.2 |
Exchange gas receivable | 70.2 |  |  | 45.7 |
Regulatory assets | 268.0 |  |  | 319.9 |
Prepayments | 138.2 |  |  | 138.5 |
Other current assets | 37.5 |  |  | 24.2 |
Total Current Assets(1) | 2,184.6 |  |  | 2,080.2 |
Other Assets |  |  |
Regulatory assets | 2,162.3 |  |  | 2,157.4 |
Goodwill | 1,485.9 |  |  | 1,485.9 |
Deferred charges and other | 609.8 |  |  | 432.0 |
Total Other Assets | 4,258.0 |  |  | 4,075.3 |
Total Assets | $ | 33,105.1 |  |  | $ | 31,788.1 |

(1)Includes $1,307.1 million and $1,323.8 million at March 31, 2025 and December 31, 2024, respectively, of net property, plant and equipment assets and $62.0 million and $65.0 million at March 31, 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.
10

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

(in millions, except share amounts) | March 31, 2025 |  | December 31, 2024 |
CAPITALIZATION AND LIABILITIES |  |  |  |
Capitalization |  |  |  |
Stockholders’ Equity |  |  |  |
Common stock - $0.01 par value,750,000,000 shares authorized; 470,618,280 and 469,822,472 shares outstanding, respectively | $ | 4.7 |  |  | $ | 4.7 |  |
Treasury stock | (99.9) |  |  | (99.9) |  |
Additional paid-in capital | 9,522.6 |  |  | 9,521.5 |  |
Retained deficit | (501.4) |  |  | (711.7) |  |
Accumulated other comprehensive loss | (29.2) |  |  | (30.4) |  |
Total NiSource Stockholders’ Equity | 8,896.8 |  |  | 8,684.2 |  |
Noncontrolling interest in consolidated subsidiaries | 2,049.2 |  |  | 1,984.1 |  |
Total Stockholders’ Equity | 10,946.0 |  |  | 10,668.3 |  |
Long-term debt, excluding amounts due within one year | 12,833.1 |  |  | 12,074.5 |  |
Total Capitalization | 23,779.1 |  |  | 22,742.8 |  |
Current Liabilities |  |  |  |
Current portion of long-term debt | 1,281.0 |  |  | 1,281.2 |  |
Short-term borrowings | 771.0 |  |  | 604.6 |  |
Accounts payable | 726.3 |  |  | 863.1 |  |
Dividends payable - common stock | 134.4 |  |  | — |  |
Customer deposits and credits | 143.2 |  |  | 268.8 |  |
Taxes accrued | 215.9 |  |  | 173.4 |  |
Interest accrued | 142.3 |  |  | 157.0 |  |
Asset retirement obligations | 50.7 |  |  | 84.6 |  |
Exchange gas payable | 59.1 |  |  | 91.8 |  |
Regulatory liabilities | 233.5 |  |  | 150.5 |  |
Accrued compensation and employee benefits | 141.5 |  |  | 268.2 |  |
Other accruals | 343.0 |  |  | 170.2 |  |
Total Current Liabilities(1) | 4,241.9 |  |  | 4,113.4 |  |
Other Liabilities |  |  |  |
Deferred income taxes | 2,353.9 |  |  | 2,281.6 |  |
Accrued liability for postretirement and postemployment benefits | 204.0 |  |  | 207.5 |  |
Regulatory liabilities | 1,461.7 |  |  | 1,431.2 |  |
Asset retirement obligations | 727.8 |  |  | 698.6 |  |
Other noncurrent liabilities and deferred credits | 336.7 |  |  | 313.0 |  |
Total Other Liabilities(1) | 5,084.1 |  |  | 4,931.9 |  |
Commitments and Contingencies (Refer to Note 14, "Other Commitments and Contingencies") |  |  |  |
Total Capitalization and Liabilities | $ | 33,105.1 |  |  | $ | 31,788.1 |  |

(1)Includes $51.5 million and $53.7 million at March 31, 2025 and December 31, 2024, respectively, of current liabilities and $53.8 million and $58.3 million at March 31, 2025 and December 31, 2024, respectively, of other liabilities, and finance leases of $40.3 million and $40.4 million at March 31, 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.
11

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

Three Months Ended March 31, (in millions) | 2025 |  | 2024
Operating Activities |  |  |
Net Income | $ | 526.7 |  |  | $ | 400.3 |
Adjustments to Reconcile Net Income to Net Cash from Operating Activities: |  |  |
Depreciation and amortization | 258.6 |  |  | 242.1 |
Deferred income taxes and investment tax credits | 91.3 |  |  | 61.6 |
Payments for asset retirement obligations | (10.4) |  |  | (12.0) |
Other adjustments | 7.1 |  |  | 7.8 |
Changes in Assets and Liabilities: |  |  |
Components of working capital(1) | (205.3) |  |  | (235.2) |
Regulatory assets/liabilities | 10.3 |  |  | 18.4 |
Deferred charges and other noncurrent assets | — |  |  | (18.0) |
Other noncurrent liabilities and deferred credits | 8.1 |  |  | (8.8) |
Net Cash Flows from Operating Activities | 686.4 |  |  | 456.2 |
Investing Activities |  |  |
Capital expenditures | (637.3) |  |  | (589.5) |
Milestone payments to renewable generation asset developer | (554.2) |  |  | (110.6) |
Advanced deposits | (125.3) |  |  | — |
Other investing activities | (35.9) |  |  | (22.9) |
Net Cash Flows used for Investing Activities | (1,352.7) |  |  | (723.0) |
Financing Activities |  |  |
Proceeds from issuance of long-term debt | 741.5 |  |  | 644.4 |
Repayments of finance lease obligations | (5.5) |  |  | (7.2) |
Repayment of short-term debt (maturity > 90 days) | — |  |  | (1,650.0) |
Net change in commercial paper and other short-term borrowings | 166.4 |  |  | (176.3) |
Issuance of common stock, net of issuance costs | 3.2 |  |  | 2.7 |
Redemption of preferred stock | — |  |  | (486.1) |
Preferred stock redemption premium | — |  |  | (14.0) |
Equity costs, premiums and other debt related costs | (15.4) |  |  | (57.6) |
Contributions from NIPSCO minority interest holders | 34.8 |  |  | — |
Distributions to tax equity partners | (4.1) |  |  | (3.0) |
Distribution to NIPSCO minority interest holders | (17.5) |  |  | — |
Dividends paid - common stock | (132.0) |  |  | (118.6) |
Dividends paid - preferred stock | — |  |  | (8.1) |
Net Cash Flows from (used for) Financing Activities | 771.4 |  |  | (1,873.8) |
Change in cash, cash equivalents and restricted cash | 105.1 |  |  | (2,140.6) |
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 | $ | 303.7 |  |  | $ | 140.5 |
(1) Refer to Note 18, "Supplemental Disclosures of Cash Flow Information," for additional information.

Reconciliation to Balance Sheet

Three Months Ended March 31, (in millions) | 2025
Cash and cash equivalents | 259.4
Restricted cash | 44.3
Total Cash, Cash Equivalents and Restricted Cash | 303.7

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 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 January 1, 2025 | $ | 4.7 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,521.5 |  |  | $ | (711.7) |  |  | $ | (30.4) |  |  | $ | 1,984.1 |  |  | $ | 10,668.3 |
Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | — |  |  | — |  |  | — |  |  | — |  |  | 474.8 |  |  | — |  |  | 51.9 |  |  | 526.7 |
Other comprehensive gain, net of tax | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 1.2 |  |  | — |  |  | 1.2 |
Dividends: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock ($0.56 per share) | — |  |  | — |  |  | — |  |  | — |  |  | (264.5) |  |  | — |  |  | — |  |  | (264.5) |
Noncontrolling Interests: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contributions from noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 34.8 |  |  | 34.8 |
Distributions to noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (21.6) |  |  | (21.6) |
Stock issuances (redemptions): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | — |  |  | — |  |  | 1.7 |  |  | — |  |  | — |  |  | — |  |  | 1.7 |
Long-term incentive plan | — |  |  | — |  |  | — |  |  | (3.3) |  |  | — |  |  | — |  |  | — |  |  | (3.3) |
401(k) and profit sharing | — |  |  | — |  |  | — |  |  | 2.7 |  |  | — |  |  | — |  |  | — |  |  | 2.7 |
Balance as of March 31, 2025 | $ | 4.7 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 9,522.6 |  |  | $ | (501.4) |  |  | $ | (29.2) |  |  | $ | 2,049.2 |  |  | $ | 10,946.0 |
(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 January 1, 2024 | $ | 4.5 |  |  | $ | 486.1 |  |  | $ | (99.9) |  |  | $ | 8,879.5 |  |  | $ | (967.0) |  |  | $ | (33.6) |  |  | $ | 1,866.7 |  |  | $ | 10,136.3 |
Comprehensive Income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | — |  |  | — |  |  | — |  |  | — |  |  | 365.0 |  |  | — |  |  | 35.3 |  |  | 400.3 |
Other comprehensive loss, net of tax | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (0.2) |  |  | — |  |  | (0.2) |
Dividends: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock ($0.53 per share) | — |  |  | — |  |  | — |  |  | — |  |  | (237.6) |  |  | — |  |  | — |  |  | (237.6) |
Preferred stock (See Note 6) | — |  |  | — |  |  | — |  |  | — |  |  | (8.1) |  |  | — |  |  | — |  |  | (8.1) |
Noncontrolling Interests: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions to noncontrolling interests | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (3.0) |  |  | (3.0) |
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 | — |  |  | — |  |  | — |  |  | 1.4 |  |  | — |  |  | — |  |  | — |  |  | 1.4 |
Long-term incentive plan | — |  |  | — |  |  | — |  |  | 3.3 |  |  | — |  |  | — |  |  | — |  |  | 3.3 |
401(k) and profit sharing | — |  |  | — |  |  | — |  |  | 2.6 |  |  | — |  |  | — |  |  | — |  |  | 2.6 |
Balance as of March 31, 2024 | $ | 4.5 |  |  | $ | — |  |  | $ | (99.9) |  |  | $ | 8,886.8 |  |  | $ | (861.7) |  |  | $ | (33.8) |  |  | $ | 1,899.0 |  |  | $ | 9,794.9 |

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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 January 1, 2025 | — |  |  | 473,785 |  |  | (3,963) |  |  | 469,822 |
Issued: |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | 46 |  |  | — |  |  | 46 |
Long-term incentive plan | — |  |  | 682 |  |  | — |  |  | 682 |
401(k) and profit sharing | — |  |  | 68 |  |  | — |  |  | 68 |
Balance as of March 31, 2025 | — |  |  | 474,581 |  |  | (3,963) |  |  | 470,618 |
| Preferred |  | Common
Shares (in thousands) | Shares |  | Shares |  | Treasury |  | Outstanding
Balance as of January 1, 2024 | 40 |  |  | 451,345 |  |  | (3,963) |  |  | 447,382 |
Issued: |  |  |  |  |  |  |
Employee stock purchase plan | — |  |  | 53 |  |  | — |  |  | 53 |
Long-term incentive plan | — |  |  | 663 |  |  | — |  |  | 663 |
401(k) and profit sharing | — |  |  | 100 |  |  | — |  |  | 100 |
Redeemed: |  |  |  |  |  |  |
Series B and B-1 Preferred Stock | (40) |  |  | — |  |  | — |  |  | — |
Balance as of March 31, 2024 | — |  |  | 452,161 |  |  | (3,963) |  |  | 448,198 |

The accompanying Notes to Condensed Consolidated Financial Statements (unaudited) are an integral part of these statements.
14

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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 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 Chief Operating Decision Maker ("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 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 is effective for annual periods beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. The Company 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.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
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):
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Three months ended March 31, 2025 (in millions) | Columbia Operations |  | NIPSCO Operations |  | Corporate and Other |  | Total
Gas Distribution |  |  |  |  |  |  |
Residential | $ | 851.2 |  |  | $ | 291.4 |  |  | $ | — |  |  | $ | 1,142.6 |
Commercial | 306.5 |  |  | 103.1 |  |  | — |  |  | 409.6 |
Industrial | 47.9 |  |  | 31.4 |  |  | — |  |  | 79.3 |
Off-system | 22.3 |  |  | — |  |  | — |  |  | 22.3 |
Wholesale | 1.1 |  |  | — |  |  | — |  |  | 1.1 |
Miscellaneous(1) | 10.9 |  |  | 4.7 |  |  | — |  |  | 15.6 |
Subtotal | $ | 1,239.9 |  |  | $ | 430.6 |  |  | $ | — |  |  | $ | 1,670.5 |
Electric Generation and Power Delivery |  |  |  |  |  |  |
Residential | $ | — |  |  | $ | 167.9 |  |  | $ | — |  |  | $ | 167.9 |
Commercial | — |  |  | 160.1 |  |  | — |  |  | 160.1 |
Industrial | — |  |  | 142.6 |  |  | — |  |  | 142.6 |
Wholesale | — |  |  | 7.6 |  |  | — |  |  | 7.6 |
Public Authority | — |  |  | 2.2 |  |  | — |  |  | 2.2 |
Miscellaneous(1) | — |  |  | (1.4) |  |  | — |  |  | (1.4) |
Subtotal | $ | — |  |  | $ | 479.0 |  |  | $ | — |  |  | $ | 479.0 |
Total Customer Revenues(2) | 1,239.9 |  |  | 909.6 |  |  | — |  |  | 2,149.5 |
Other Revenues(3) | 0.7 |  |  | 31.8 |  |  | 1.2 |  |  | 33.7 |
Total Operating Revenues | $ | 1,240.6 |  |  | $ | 941.4 |  |  | $ | 1.2 |  |  | $ | 2,183.2 |
(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 March 31, 2024 (in millions) | Columbia Operations |  | NIPSCO Operations |  | Corporate and Other |  | Total
Gas Distribution |  |  |  |  |  |  |
Residential | $ | 628.0 |  |  | $ | 212.1 |  |  | $ | — |  |  | $ | 840.1 |
Commercial | 220.4 |  |  | 74.7 |  |  | — |  |  | 295.1 |
Industrial | 40.1 |  |  | 23.8 |  |  | — |  |  | 63.9 |
Off-system | 12.8 |  |  | — |  |  | — |  |  | 12.8 |
Wholesale | 0.8 |  |  | — |  |  | — |  |  | 0.8 |
Miscellaneous(1) | 8.2 |  |  | 7.9 |  |  | — |  |  | 16.1 |
Subtotal | $ | 910.3 |  |  | $ | 318.5 |  |  | $ | — |  |  | $ | 1,228.8 |
Electric Generation and Power Delivery |  |  |  |  |  |  |
Residential | $ | — |  |  | $ | 143.8 |  |  | $ | — |  |  | $ | 143.8 |
Commercial | — |  |  | 142.9 |  |  | — |  |  | 142.9 |
Industrial | — |  |  | 115.9 |  |  | — |  |  | 115.9 |
Wholesale | — |  |  | 6.3 |  |  | — |  |  | 6.3 |
Public Authority | — |  |  | 2.1 |  |  | — |  |  | 2.1 |
Miscellaneous(1) | — |  |  | 3.2 |  |  | — |  |  | 3.2 |
Subtotal | $ | — |  |  | $ | 414.2 |  |  | $ | — |  |  | $ | 414.2 |
Total Customer Revenues(2) | 910.3 |  |  | 732.7 |  |  | — |  |  | 1,643.0 |
Other Revenues(3) | 43.4 |  |  | 19.7 |  |  | 0.2 |  |  | 63.3 |
Total Operating Revenues | $ | 953.7 |  |  | $ | 752.4 |  |  | $ | 0.2 |  |  | $ | 1,706.3 |
(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 opening and closing balances of customer receivables for the three months ended March 31, 2025 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 March 31, 2025 | 777.4 |  |  | 299.5 |  |  |

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 March 31, 2025 and December 31, 2024 are presented in the table below:

(in millions) | Columbia Operations |  | NIPSCO Operations |  |  |  | Corporate and Other |  | Total
Balance as of January 1, 2025 | $ | 9.8 |  |  | $ | 13.9 |  |  |  |  | $ | — |  |  | $ | 23.7 |
Current period provisions | 9.1 |  |  | 4.1 |  |  |  |  | — |  |  | 13.2 |
Write-offs charged against allowance | (7.8) |  |  | (2.6) |  |  |  |  | — |  |  | (10.4) |
Recoveries of amounts previously written off | 2.9 |  |  | 0.2 |  |  |  |  | — |  |  | 3.1 |
Balance as of March 31, 2025 | $ | 14.0 |  |  | $ | 15.6 |  |  |  |  | $ | — |  |  | $ | 29.6 |

(in millions) | Columbia Operations |  | NIPSCO Operations |  |  |  | Corporate and Other |  | Total
Balance as of January 1, 2024 | $ | 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) | March 31, 2025 |  | December 31, 2024
Net property, plant and equipment | $ | 1,307.1 |  |  | $ | 1,323.8 |
Current assets | 62.0 |  |  | 65.0 |
Total assets(1) | 1,369.1 |  |  | 1,388.8 |
Current liabilities | 51.5 |  |  | 53.7 |
Asset retirement obligations | 53.8 |  |  | 58.3 |
Finance lease obligations | 40.3 |  |  | 40.4 |
Total liabilities(1)(2) | $ | 145.6 |  |  | $ | 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 March 31, 2025.
Voting Interest Entities. We retain a controlling financial interest in NIPSCO Holdings II and its subsidiaries and consolidate their financial results. During the first quarter of 2025, we received $34.8 million of contributions and we made $17.5 million of distributions to our NIPSCO minority interest holders based on their relative ownership percentages. There were no contributions or distributions made during the first quarter of 2024.
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 March 31, |  |
(in millions, except per share amounts) | 2025 |  | 2024 |  |  |  |
Numerator: |  |  |  |  |  |  |
Net Income Available to Common Shareholders | $ | 474.8 |  |  | $ | 344.3 |  |  |  |  |
Less: Income allocated to participating securities | 0.8 |  |  | 0.3 |  |  |  |  |
Net Income Available to Common Shareholders - Basic | 474.0 |  |  | 344.0 |  |  |  |  |
Net Income Available to Common Shareholders - Diluted | $ | 474.0 |  |  | $ | 344.0 |  |  |  |  |
Denominator: |  |  |  |  |  |  |
Average common shares outstanding - Basic | 470.4 |  |  | 447.9 |  |  |  |  |
Dilutive potential common shares: |  |  |  |  |  |  |
Shares contingently issuable under employee stock plans | 1.4 |  |  | 0.9 |  |  |  |  |
Shares restricted under employee stock plans | 0.7 |  |  | 0.4 |  |  |  |  |
ATM forward sale agreements | — |  |  | 0.2 |  |  |  |  |
Average Common Shares - Diluted | 472.5 |  |  | 449.4 |  |  |  |  |
Earnings per common share: |  |  |  |  |  |  |
Basic | $ | 1.01 |  |  | $ | 0.77 |  |  |  |  |
Diluted | $ | 1.00 |  |  | $ | 0.77 |  |  |  |  |

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 allows 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. We may settle the forward sale agreement in shares, cash or net shares by December 31, 2025. Had we settled all the shares under the forward sale agreement at March 31, 2025, we would have received approximately $79.8 million, based on a net price of $39.92 per share.
In March 2025, we executed a forward sale agreement, which allows 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. We may settle the forward sale agreement in shares, cash or net shares by December 31, 2025. Had we settled all the shares under the forward sale agreement at March 31, 2025, we would have received approximately $69.7 million, based on a net price of $40.80 per share.
As of March 31, 2025, the ATM program (inclusive of the forward sale agreements) had approximately $147.5 million of equity available for issuance. The program expires on December 31, 2025.
Series B and B-1 Preferred Stock. Dividends declared per share for the Series B Preferred Stock were zero and $406.25 during the three months ended March 31, 2025 and 2024, respectively.
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.
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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, provide for issuance of letters of credit and also for 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 March 31, 2025 and December 31, 2024.
Commercial Paper Program. Our commercial paper program has a program limit of $1.85 billion. We had $521.0 million and $604.6 million of commercial paper outstanding with weighted-average interest rates of 4.75% and 4.73% as of March 31, 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 August 2025 and May 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 March 31, 2025, the maximum amount of debt that could be borrowed related to our accounts receivable programs was $375.0 million.
We had $250.0 million and zero of short-term borrowings related to the securitization transactions as of March 31, 2025 and December 31, 2024, respectively.
For the three months ended March 31, 2025, $250.0 million was recorded as cash flows from financing activities related to the change in short-term borrowings due to securitization transactions. For the three months ended March 31, 2024, $337.6 million was recorded as cash flows 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.
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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, after notice and hearing, issue an order modifying its February 13, 2023 order that approved a power purchase agreement related to the Templeton project and allow for NIPSCO to fully own the Templeton project. A final order expected in October 2025.
NIPSCO Generation filing. In January 2025, NIPSCO Generation, a subsidiary of NIPSCO Holdings II, 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. An order is expected in the third quarter of 2025.
NIPSCO Electric rate case filing. On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC. Under the Settlement Agreement, new rates are implemented in 2 steps, with implementation of Step 1 rates effective no later than September 2025 and Step 2 rates to be effective 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:

| March 31, 2025 |  | December 31, 2024
(in millions) | Assets |  | Liabilities |  | Assets |  | Liabilities
Current(1) |  |  |  |  |  |  |
Derivatives not designated as hedging instruments | $ | 31.5 |  |  | $ | 2.2 |  |  | $ | 9.1 |  |  | $ | 2.3 |
Total | $ | 31.5 |  |  | $ | 2.2 |  |  | $ | 9.1 |  |  | $ | 2.3 |
Noncurrent(2) |  |  |  |  |  |  |
Derivatives not designated as hedging instruments | $ | 20.2 |  |  | $ | 1.4 |  |  | $ | 17.9 |  |  | $ | 1.2 |
Total | $ | 20.2 |  |  | $ | 1.4 |  |  | $ | 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).
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 March 31, 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 $48.1 million and $23.5 million at March 31, 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
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
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 March 31, 2025 and December 31, 2024, we had 73.3 MMDth and 77.8 MMDth, respectively, of net energy derivative volumes outstanding related to our natural gas hedges.
NIPSCO has received IURC approval 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 March 31, 2025, the remaining terms of these instruments range from one to two years. Likewise, Columbia of Pennsylvania has received approval for a 24-month rolling hedge program. The hedging program was executed in December 2023, with an effective date of April 1, 2024 and will continue in perpetuity. The program is designed to financially hedge approximately 20% of the customers' annual demand. 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) | March 31, 2025 |  | December 31, 2024
Regulatory Assets |  |  |
Losses on commodity price risk programs | $ | 3.7 |  |  | $ | 6.5 |
Regulatory Liabilities |  |  |
Gains on commodity price risk programs | 59.7 |  |  | 28.7 |

Our derivative instruments measured at fair value as of March 31, 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 March 31, 2025 and December 31, 2024 we had no active interest rate swap positions. The overall net loss related to our multiple settled interest rate swaps is recorded in AOCI. We amortize the net loss over the life of the debt associated with these swaps as we recognize interest expense. These amounts are immaterial for the three months ended March 31, 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 March 31, 2025 and December 31, 2024:

Recurring Fair Value Measurements March 31, 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 March 31, 2025
Assets |  |  |  |  |  |  |
U.S. Treasury debt securities(1) | $ | 41.5 |  |  | $ | — |  |  | $ | — |  |  | $ | 41.5 |
Risk management assets | — |  |  | 51.7 |  |  | — |  |  | 51.7 |
Available-for-sale debt securities | — |  |  | 81.2 |  |  | — |  |  | 81.2 |
Total | $ | 41.5 |  |  | $ | 132.9 |  |  | $ | — |  |  | $ | 174.4 |
Liabilities |  |  |  |  |  |  |
Risk management liabilities | $ | — |  |  | $ | 3.6 |  |  | $ | — |  |  | $ | 3.6 |
Total | $ | — |  |  | $ | 3.6 |  |  | $ | — |  |  | $ | 3.6 |

(1) Treasury bills are presented in "Cash and cash equivalents" and "Restricted cash" on the Consolidated Balance Sheets.

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.
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.
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.
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. We use a similar model
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
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.
Credit risk is considered in the fair value calculation of derivative instruments that are not exchange-traded. Credit exposures are adjusted to reflect collateral agreements that reduce exposures. As of March 31, 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.
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.
26

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

March 31, 2025 (in millions) | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses(1) |  | Allowance for Credit Losses |  | Fair Value
Available-for-sale debt securities |  |  |  |  |  |  |  |  |
Corporate/Other debt securities | $ | 85.5 |  |  | $ | 0.6 |  |  | $ | (4.7) |  |  | $ | (0.2) |  |  | $ | 81.2 |
Total | $ | 85.5 |  |  | $ | 0.6 |  |  | $ | (4.7) |  |  | $ | (0.2) |  |  | $ | 81.2 |
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 Corporate/Other debt securities in an unrealized loss position without an allowance for credit losses is $63.7 million at March 31, 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 $0.0 million and $0.4 million for the three months ended March 31, 2025 and 2024, respectively.
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 March 31, 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 March 31, 2025 |  | Estimated Fair Value as of March 31, 2025 |  | Carrying Amount as of Dec. 31, 2024 |  | Estimated Fair Value as of Dec. 31, 2024
Long-term debt (including current portion) | $ | 14,114.1 |  |  | $ | 13,292.4 |  |  | $ | 13,355.7 |  |  | $ | 12,505.2 |

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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 March 31, 2025 and 2024 were 16.7% and 16.0%, 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 0.7% in 2025 compared to 2024 is primarily driven by higher state income taxes and an increase to pretax income, which reduced the relative impact of permanent differences.
As of March 31, 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.
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. The majority of 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 three months ended March 31, 2025 and 2024, we contributed $0.5 million and $0.7 million, respectively to our pension plans and $4.9 million and $5.4 million, respectively to our OPEB plans.
The following table provides the components of the plans' actuarially determined net periodic benefit cost for the three months ended March 31, 2025 and 2024:

| Pension Benefits |  | OPEB
Three Months Ended March 31, (in millions) | 2025 |  | 2024 |  | 2025 |  | 2024
Components of Net Periodic Benefit Cost(1) |  |  |  |  |  |  |
Service cost | $ | 4.9 |  |  | $ | 5.4 |  |  | $ | 1.0 |  |  | $ | 1.3 |
Interest cost | 16.0 |  |  | 16.3 |  |  | 5.6 |  |  | 5.4 |
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 |
Total Net Periodic Benefit Cost | $ | 4.2 |  |  | $ | 5.1 |  |  | $ | 2.4 |  |  | $ | 3.1 |
(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).

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 March 31, 2025 and December 31, 2024, we had issued stand-by letters of credit of $9.4 million for the benefit of third parties.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
We provide guarantees related to our future performance under BTAs for our renewable generation projects. At March 31, 2025 and December 31, 2024, our guarantees for multiple BTAs totaled $465.4 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 March 31, 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 $61.7 million.
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 March 31, 2025 and December 31, 2024, we had recorded a liability of $90.4 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 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 complete an annual refresh of the model in the second quarter of each fiscal year. Our total estimated liability related to the facilities subject to remediation was $83.8 million and $86.4 million at March 31, 2025 and December 31, 2024, respectively.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
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 $16.3 million 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. Facility evaluations for CCRMUs are required by February 2026 and 2027. 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.
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, has filed a CPCN with the IURC, seeking approval of the full ownership BTA structure. Other than Templeton BTA, NIPSCO has received IURC approval for all of its BTAs. In addition to IURC approval, NIPSCO's purchase obligation under certain BTAs is dependent on timely completion of construction. Certain agreements require NIPSCO to make partial payments upon the developer's completion of significant construction milestones. With respect to BTAs for which tax equity partnerships are utilized, once the tax equity partner has earned its negotiated rate of return and we have reached the agreed upon contractual date, NIPSCO has the option to purchase at fair market value the remaining interest in the JV from the tax equity partner.
In January 2025, Fairbanks achieved mechanical completion, resulting in NIPSCO making a $336.6 million payment to the developer. The company recorded a liability totaling $144.1 million on the Condensed Consolidated Balance Sheets (unaudited) as other accruals, which will be paid to the developer upon substantial completion. In January 2025, Dunns Bridge II achieved substantial completion, resulting in NIPSCO making a $217.6 million payment to the developer in February 2025.
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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 January 1, 2025 | $ | (4.0) |  |  | $ | (13.2) |  |  | $ | (13.2) |  |  | $ | (30.4) |
Other comprehensive income before reclassifications | 0.8 |  |  | — |  |  | 0.3 |  |  | 1.1 |
Amounts reclassified from accumulated other comprehensive loss | — |  |  | (0.1) |  |  | 0.2 |  |  | 0.1 |
Net current-period other comprehensive income (loss) | 0.8 |  |  | (0.1) |  |  | 0.5 |  |  | 1.2 |
Balance as of March 31, 2025 | $ | (3.2) |  |  | $ | (13.3) |  |  | $ | (12.7) |  |  | $ | (29.2) |

(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 January 1, 2024 | $ | (7.3) |  |  | $ | (12.8) |  |  | $ | (13.5) |  |  | $ | (33.6) |
Other comprehensive loss before reclassifications | (0.6) |  |  | (0.2) |  |  | (0.1) |  |  | (0.9) |
Amounts reclassified from accumulated other comprehensive loss | 0.3 |  |  | 0.1 |  |  | 0.3 |  |  | 0.7 |
Net current-period other comprehensive income (loss) | (0.3) |  |  | (0.1) |  |  | 0.2 |  |  | (0.2) |
Balance as of March 31, 2024 | $ | (7.6) |  |  | $ | (12.9) |  |  | $ | (13.3) |  |  | $ | (33.8) |

(1)All amounts are net of tax. Amounts in parentheses indicate debits.
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 fully 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 Chief Operating Decision Maker, the CEO, who utilizes it to assess performance and allocation 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.
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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)

Three Months Ended March 31, 2025 |  |
(in millions) | Columbia Operations |  | NIPSCO Operations |  | Total of Reportable Segments |  |  |  |
Operating Revenues |  |  |  |  |  |  |  |  |
External Revenue | $ | 1,240.6 |  |  | $ | 941.4 |  |  | $ | 2,182.0 |  |  |  |  |
Intersegment Revenue | 3.2 |  |  | 0.3 |  |  | 3.5 |  |  |  |  |
Total Operating Revenue | $ | 1,243.8 |  |  | $ | 941.7 |  |  | $ | 2,185.5 |  |  |  |  |
Cost of energy | 379.8 |  |  | 267.7 |  |  | 647.5 |  |  |  |  |
O&M | 243.0 |  |  | 202.0 |  |  | 445.0 |  |  |  |  |
Depreciation | 108.2 |  |  | 141.3 |  |  | 249.5 |  |  |  |  |
Total other taxes | 67.0 |  | 18.5 |  | 85.5 |  |  |  |  |
Other segment items(1) | — |  |  | 0.3 |  |  | 0.3 |  |  |  |  |
Operating Income | $ | 445.8 |  |  | $ | 311.9 |  |  | $ | 757.7 |  |  |  |  |

(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.

Three Months Ended March 31, 2024 |  |
(in millions) | Columbia Operations |  | NIPSCO Operations |  | Total of Reportable Segments |  |  |  |
Operating Revenues |  |  |  |  |  |  |  |  |
External Revenue | $ | 953.7 |  |  | $ | 752.4 |  |  | $ | 1,706.1 |  |  |  |  |
Intersegment Revenue | 3.2 |  |  | 0.3 |  |  | 3.5 |  |  |  |  |
Total Operating Revenue | 956.9 |  |  | 752.7 |  |  | 1,709.6 |  |  |  |  |
Cost of energy | 228.8 |  |  | 196.2 |  |  | 425.0 |  |  |  |  |
O&M | 210.7 |  |  | 191.3 |  |  | 402.0 |  |  |  |  |
Depreciation | 98.2 |  |  | 132.7 |  |  | 230.9 |  |  |  |  |
Total other taxes | 57.2 |  | 16.1 |  | 73.3 |  |  |  |
Operating Income | $ | 362.0 |  |  | $ | 216.4 |  |  | $ | 578.4 |  |  |  |  |

The following table provides information about the assets of our reportable segments included in the Condensed Consolidated Balance Sheet (unaudited):

(in millions) | March 31, 2025 |  | December 31, 2024
Assets |  |  |
Columbia Operations | $ | 14,962.2 |  |  | $ | 14,769.5 |
NIPSCO Operations | 16,807.4 |  |  | 15,823.5 |
Corporate and Other | 1,335.5 |  |  | 1,195.1 |
Consolidated Assets | $ | 33,105.1 |  |  | $ | 31,788.1 |

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ITEM 1. FINANCIAL STATEMENTS (continued)
NiSource Inc.
Notes to Condensed Consolidated Financial Statements (unaudited) (continued)
To reconcile the segment tables above to consolidated NiSource:

Three Months Ended March 31, 2025
(in millions) | Total Reportable Segments |  | Corporate and Other |  | Eliminations |  | Consolidated NiSource
Total Operating Revenue | $ | 2,185.5 |  |  | $ | 145.4 |  |  | $ | (147.7) |  |  | $ | 2,183.2 |
Operating Income | 757.7 |  |  | 1.7 |  |  | — |  |  | 759.4 |

Three Months Ended March 31, 2024
(in millions) | Total Reportable Segments |  | Corporate and Other |  | Eliminations |  | Consolidated NiSource
Total Operating Revenue | $ | 1,709.6 |  |  | $ | 140.1 |  |  | $ | (143.4) |  |  | $ | 1,706.3 |
Operating Income | 578.4 |  |  | 5.0 |  |  | — |  |  | 583.4 |

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

| Three Months Ended March 31, |  |
(in millions) | 2025 |  | 2024 |  |  |  |
Interest income | $ | 2.0 |  |  | $ | 2.5 |  |  |  |  |
AFUDC equity | 9.2 |  |  | 11.3 |  |  |  |  |
Pension and other postretirement non-service cost | (3.8) |  |  | (2.2) |  |  |  |  |
Miscellaneous | (1.6) |  |  | (2.4) |  |  |  |  |
Total Other, net | $ | 5.8 |  |  | $ | 9.2 |  |  |  |  |

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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 Statements of Consolidated Cash flows (unaudited):

| Three Months Ended March 31, |  |
(in millions) | 2025 |  | 2024 |  |  |  |
Accounts receivable | $ | (141.5) |  |  | $ | 16.4 |  |  |  |  |
Inventories | 127.7 |  |  | 173.8 |  |  |  |  |
Accounts payable | (59.3) |  |  | (90.6) |  |  |  |  |
Customer deposits and credits | (125.6) |  |  | (104.9) |  |  |  |  |
Taxes accrued | 34.2 |  |  | 7.5 |  |  |  |  |
Interest accrued | (14.8) |  |  | 12.4 |  |  |  |  |
Exchange gas receivable/payable | 40.9 |  |  | (114.0) |  |  |  |  |
Other accruals | 28.6 |  |  | (7.4) |  |  |  |  |
Prepayments and other current assets | (20.0) |  |  | (67.7) |  |  |  |  |
Accrued compensation and employee benefits | (75.5) |  |  | (60.7) |  |  |  |  |
Total change in working capital | $ | (205.3) |  |  | $ | (235.2) |  |  |  |  |

Three Months Ended March 31, (in millions) | 2025 |  | 2024
Non-cash transactions: |  |  |
Capital expenditures included in current liabilities | $ | 394.2 |  |  | $ | 239.7 |
Dividends declared but not paid | 134.4 |  |  | 119.0 |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
NiSource Inc.

Index | Page
Executive Summary | 36
Summary of Consolidated Financial Results | 38
Results and Discussion of Segment Operations | 39
Columbia Operations | 40
NIPSCO Operations | 43
Liquidity and Capital Resources | 48
Regulatory, Environmental and Safety Matters | 52
Market Risk Disclosures | 55
Other Information | 56

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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 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, which are summarized for financial reporting purposes into two primary reportable segments: Columbia Operations and NIPSCO Operations. Refer to ''Note 16, "Business Segment Information," 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.
Energy Transition: We continue to advance our energy transition strategy, primarily through the continuation and enhancement of existing programs, such as retiring and replacing 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 March 31, 2025, we have placed in service owned renewable and storage projects, developed under BTAs, with combined nameplate capacities of 1,500 MW and 101 MW respectively. Renewable PPA projects with a combined nameplate capacity of 600 MW have also been placed in service. In addition, renewable BTA projects with combined nameplate capacities of 650 MW, and renewable PPA projects with a combined nameplate capacity of 600 MW were under development as of March 31, 2025, all of which have received IURC approval, with the exception of the Templeton project, which is currently pending approval. The capacity figure for BTA projects in development includes the Templeton project. 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. In 2024, the IURC approved full ownership of the Cavalry, Dunns Bridge II, Fairbanks and Gibson and the cost of the Fairbanks project as contemplated in contractual actions. Full ownership of these projects allows NIPSCO to leverage provisions of the IRA, monetize renewable tax credits more effectively, and provide enhanced benefits to customers as compared to the previous tax equity partnership structure approved by the IURC. We remain on track to retire R.M Schahfer's remaining two coal units by the end of 2025. For additional information, see "Results and Discussion of Operations - NIPSCO Operations," in this Management's Discussion, and see item 1A. Risk Factors in this Quarterly Report on Form 10-Q.
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. In 2024, Sugar Creek completed an Advanced Gas Path Tech upgrade that enhanced its overall production capabilities. 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. In October 2024, we received approval for the issuance of a CPCN for an approximately 400 MW natural gas peaking generation facility from the IURC to replace R.M. Schahfer's existing peaking facilities. The planned retirement of the two vintage gas peaking facilities at the R.M. Schahfer Generating Station is also expected to occur by the end of 2028. Final retirement dates for these units, as well as Michigan City, will be subject to MISO approval.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
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, new EPA emissions rules, and evolving MISO resource accreditation rules. Customer interest related to data center development in our northern Indiana service territory has accelerated. 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 are evaluating the potential for data center development in our service territory, including ways to effectively manage the potential power demand, generation sources, and transmission capabilities to meet potential load growth from any data center customer, while at the same time focusing on our environmental goals. We expect the management of large load growth would require new generation resources. 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. We are making progress towards our transformation goals with a successful completion of the first phase of our WAM program, an enterprise resource planning system that will optimize the scheduling, dispatch, and execution of our field operations. This phase of the program implemented the solution within our electric distribution and transmission operations, while remaining phases for gas distribution operations and generation operations are anticipated to be completed by the end of 2025. In addition to transforming technology to enhance our employee and customer experiences, 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 see increasing prices associated with certain materials and supplies and are tracking the potential impact of new and proposed 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.
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".
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
Summary of Consolidated Financial Results
A summary of our consolidated financial results for the three months ended March 31, 2025 and 2024 are presented below:

| Three Months Ended March 31, |  |
(in millions, except per share amounts) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  |  |  |  |  |
Operating Revenues | $ | 2,183.2 |  |  | $ | 1,706.3 |  |  | $ | 476.9 |  |  |  |  |  |  |
Operating Expenses |  |  |  |  |  |  |  |  |  |  |
Cost of energy | 647.5 |  |  | 425.0 |  |  | (222.5) |  |  |  |  |  |  |
Other Operating Expenses | 776.3 |  |  | 697.9 |  |  | (78.4) |  |  |  |  |  |  |
Total Operating Expenses | 1,423.8 |  |  | 1,122.9 |  |  | (300.9) |  |  |  |  |  |  |
Operating Income | 759.4 |  |  | 583.4 |  |  | 176.0 |  |  |  |  |  |  |
Total Other Deductions, Net | (127.0) |  |  | (107.1) |  |  | (19.9) |  |  |  |  |  |  |
Income Taxes | 105.7 |  |  | 76.0 |  |  | (29.7) |  |  |  |  |  |  |
Net Income | 526.7 |  |  | 400.3 |  |  | 126.4 |  |  |  |  |  |  |
Net income attributable to noncontrolling interest | 51.9 |  |  | 35.3 |  |  | (16.6) |  |  |  |  |  |  |
Net Income Attributable to NiSource | 474.8 |  |  | 365.0 |  |  | 109.8 |  |  |  |  |  |  |
Preferred dividends and redemption premium | — |  |  | (20.7) |  |  | 20.7 |  |  |  |  |  |  |
Net Income Available to Common Shareholders | 474.8 |  |  | 344.3 |  |  | 130.5 |  |  |  |  |  |  |
Earnings Per Share |  |  |  |  |  |  |  |  |  |  |
Basic Earnings Per Share | $ | 1.01 |  |  | $ | 0.77 |  |  | $ | 0.24 |  |  |  |  |  |  |
Diluted Earnings Per Share | $ | 1.00 |  |  | $ | 0.77 |  |  | $ | 0.23 |  |  |  |  |  |  |

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 months ended March 31, 2025 was primarily due to higher revenues driven by our capital investments, partially offset by higher operating expenses, including increased depreciation expense attributed to our net plant balances and higher interest expense. See Note 6, "Equity," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for additional information.
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.
We continue to monitor and evaluate the impacts of final or proposed income tax regulations issued on provisions of the IRA including but not limited to renewable energy tax credits.
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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 fully 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.
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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 months ended March 31, 2025 and 2024 are presented below.

| Three Months Ended March 31, |  |
(in millions) | 2025 |  | 2024 |  | Favorable (Unfavorable) |  |  |  |  |  |
Operating Revenues | $ | 1,243.8 |  |  | $ | 956.9 |  |  | $ | 286.9 |  |  |  |  |  |  |
Operating Expenses |  |  |  |  |  |  |  |  |  |  |
Cost of energy | 379.8 |  |  | 228.8 |  |  | (151.0) |  |  |  |  |  |  |
Operation and maintenance | 243.0 |  |  | 210.7 |  |  | (32.3) |  |  |  |  |  |  |
Depreciation and amortization | 108.2 |  |  | 98.2 |  |  | (10.0) |  |  |  |  |  |  |
Other taxes | 67.0 |  |  | 57.2 |  |  | (9.8) |  |  |  |  |  |  |
Total Operating Expenses | 798.0 |  |  | 594.9 |  |  | (203.1) |  |  |  |  |  |  |
Operating Income | $ | 445.8 |  |  | $ | 362.0 |  |  | $ | 83.8 |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  |
Residential | $ | 858.0 |  |  | $ | 665.8 |  |  | $ | 192.2 |  |  |  |  |  |  |
Commercial | 308.1 |  |  | 225.3 |  |  | 82.8 |  |  |  |  |  |  |
Industrial | 48.2 |  |  | 40.4 |  |  | 7.8 |  |  |  |  |  |  |
Off-System | 22.3 |  |  | 12.7 |  |  | 9.6 |  |  |  |  |  |  |
Other | 7.2 |  |  | 12.7 |  |  | (5.5) |  |  |  |  |  |  |
Total | $ | 1,243.8 |  |  | $ | 956.9 |  |  | $ | 286.9 |  |  |  |  |  |  |
Sales and Transportation (MMDth) |  |  |  |  |  |  |  |  |  |  |
Residential | 90.8 |  |  | 77.0 |  |  | 13.8 |  |  |  |  |  |  |
Commercial | 61.9 |  |  | 54.3 |  |  | 7.6 |  |  |  |  |  |  |
Industrial | 72.1 |  |  | 68.5 |  |  | 3.6 |  |  |  |  |  |  |
Off-System | 5.9 |  |  | 7.3 |  |  | (1.4) |  |  |  |  |  |  |
Other | 0.2 |  |  | 0.2 |  |  | — |  |  |  |  |  |  |
Total | 230.9 |  |  | 207.3 |  |  | 23.6 |  |  |  |  |  |  |
Heating Degree Days(1) | 2,670 |  |  | 2,284 |  |  | 386 |  |  |  |  |  |  |
Normal Heating Degree Days(1) | 2,666 |  |  | 2,739 |  |  | (73) |  |  |  |  |  |  |
% Warmer than Normal | — | % |  | (17) | % |  |  |  |  |  |  |  |
% Colder than prior year | 17 | % |  |  |  |  |  |  |  |  |  |
Columbia Operations Customers |  |  |  |  |  |  |  |  |  |  |
Residential | 2,233,968 |  |  | 2,222,345 |  |  | 11,623 |  |  |  |  |  |  |
Commercial | 189,918 |  |  | 189,394 |  |  | 524 |  |  |  |  |  |  |
Industrial | 1,988 |  |  | 1,980 |  |  | 8 |  |  |  |  |  |  |
Other | 5 |  |  | 5 |  |  | — |  |  |  |  |  |  |
Total | 2,425,879 |  | 2,413,724 |  |  |  |  |  |  |  |

(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 months ended March 31, 2025 compared to the same period in 2024 are presented below.

| Favorable (Unfavorable)
Changes in Operating Revenues (in millions) | Three Months Ended March 31, 2025 vs 2024 |  |  |  |
New rates from base rate proceedings and regulatory capital programs | $ | 73.2 |  |  |  |  |
The effects of weather in 2025 compared to 2024 | 27.2 |  |  |  |  |
The effects of customer growth | 1.6 |  |  |  |  |
The effects of customer usage | (6.3) |  |  |  |  |
Other | (0.2) |  |  |  |  |
Change in operating revenues (before cost of energy and other tracked items) | $ | 95.5 |  |  |  |  |
Operating revenues offset in operating expense |  |  |  |  |
Higher cost of energy billed to customers | 151.0 |  |  |  |  |
Higher tracker deferrals within operation and maintenance, depreciation, and tax | 40.4 |  |  |  |  |
Total change in operating revenues | $ | 286.9 |  |  |  |  |

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 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 three months ended March 31, 2025, compared to the same period in 2024, is primarily attributable to an increase for residential and commercial customers due to 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 months ended March 31, 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 March 31, 2025 vs 2024 |  |  |  |
Higher depreciation and amortization expense | $ | (10.0) |  |  |  |  |
Higher employee and administrative related expenses | (6.0) |  |  |  |  |
Higher property tax | (3.0) |  |  |  |  |
Other | 7.3 |  |  |  |  |
Change in operating expenses (before cost of energy and other tracked items) | $ | (11.7) |  |  |  |  |
Operating expenses offset in operating revenue |  |  |  |  |
Higher cost of energy billed to customers | (151.0) |  |  |  |  |
Higher tracker deferrals within operation and maintenance, depreciation, and tax | (40.4) |  |  |  |  |
Total change in operating expense | $ | (203.1) |  |  |  |  |

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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 months ended March 31, 2025 and 2024 are presented below.

|  |  | Three Months Ended March 31,
(in millions) |  |  |  |  |  |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
NIPSCO Operations |  |  |  |  |  |  |  |  |  |  |
Operating Revenues |  |  |  |  |  |  | $ | 941.7 |  |  | $ | 752.7 |  |  | $ | 189.0 |
Operating Expenses |  |  |  |  |  |  |  |  |  |  |
Cost of energy |  |  |  |  |  |  | 267.7 |  |  | 196.2 |  |  | (71.5) |
Operation and maintenance |  |  |  |  |  |  | 202.0 |  |  | 191.3 |  |  | (10.7) |
Depreciation and amortization |  |  |  |  |  |  | 141.3 |  |  | 132.7 |  |  | (8.6) |
Loss on impairment |  |  |  |  |  |  | 0.3 |  |  | — |  |  | (0.3) |
Other taxes |  |  |  |  |  |  | 18.5 |  |  | 16.1 |  |  | (2.4) |
Total Operating Expenses |  |  |  |  |  |  | 629.8 |  |  | 536.3 |  |  | (93.5) |
Operating Income |  |  |  |  |  |  | $ | 311.9 |  |  | $ | 216.4 |  |  | $ | 95.5 |
|  |  | Three Months Ended March 31,
(in millions) |  |  |  |  |  |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
NIPSCO Electric |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | $ | 167.9 |  |  | $ | 143.8 |  |  | $ | 24.1 |
Commercial |  |  |  |  |  |  | 160.1 |  |  | 142.9 |  |  | 17.2 |
Industrial |  |  |  |  |  |  | 142.8 |  |  | 116.1 |  |  | 26.7 |
Wholesale and Other |  |  |  |  |  |  | 30.4 |  |  | 31.2 |  |  | (0.8) |
Total |  |  |  |  |  |  | $ | 501.2 |  |  | $ | 434.0 |  |  | $ | 67.2 |
Sales (GWh) |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 810.4 |  |  | 764.9 |  |  | 45.5 |
Commercial |  |  |  |  |  |  | 884.8 |  |  | 878.7 |  |  | 6.1 |
Industrial |  |  |  |  |  |  | 2,136.0 |  |  | 1,832.7 |  |  | 303.3 |
Wholesale and Other |  |  |  |  |  |  | 180.5 |  |  | 172.6 |  |  | 7.9 |
Total |  |  |  |  |  |  | 4,011.7 |  |  | 3,648.9 |  |  | 362.8 |
NIPSCO Electric Customers |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 431,351 |  |  | 428,035 |  |  | 3,316 |
Commercial |  |  |  |  |  |  | 59,286 |  |  | 58,883 |  |  | 403 |
Industrial |  |  |  |  |  |  | 2,112 |  |  | 2,120 |  |  | (8) |
Wholesale and Other |  |  |  |  |  |  | 707 |  |  | 711 |  |  | (4) |
Total |  |  |  |  |  |  | 493,456 |  |  | 489,749 |  |  | 3,707 |

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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 March 31,
(in millions) |  |  |  |  |  |  | 2025 |  | 2024 |  | Favorable (Unfavorable)
NIPSCO Gas |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | $ | 298.7 |  |  | $ | 212.1 |  |  | $ | 86.6 |
Commercial |  |  |  |  |  |  | 105.1 |  |  | 74.7 |  |  | 30.4 |
Industrial |  |  |  |  |  |  | 31.4 |  |  | 23.8 |  |  | 7.6 |
Other |  |  |  |  |  |  | 5.3 |  |  | 8.1 |  |  | (2.8) |
Total |  |  |  |  |  |  | $ | 440.5 |  |  | $ | 318.7 |  |  | $ | 121.8 |
Sales and Transportation Volumes (MMDth) |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 32.7 |  |  | 28.6 |  |  | 4.1 |
Commercial |  |  |  |  |  |  | 20.3 |  |  | 17.7 |  |  | 2.6 |
Industrial |  |  |  |  |  |  | 73.8 |  |  | 70.2 |  |  | 3.6 |
Total |  |  |  |  |  |  | 126.8 |  |  | 116.5 |  |  | 10.3 |
Heating Degree Days |  |  |  |  |  |  | 3,015 |  |  | 2,643 |  |  | 372 |
Normal Heating Degree Days |  |  |  |  |  |  | 3,079 |  |  | 3,141 |  |  | (62) |
% Warmer than Normal |  |  |  |  |  |  | (2) | % |  | (16) | % |  |
% Colder than prior year |  |  |  |  |  |  | 14 | % |  |  |  |
NIPSCO Gas Customers |  |  |  |  |  |  |  |  |  |  |
Residential |  |  |  |  |  |  | 803,206 |  |  | 797,326 |  |  | 5,880 |
Commercial |  |  |  |  |  |  | 66,699 |  |  | 66,485 |  |  | 214 |
Industrial |  |  |  |  |  |  | 2,721 |  |  | 2,784 |  |  | (63) |
Total |  |  |  |  |  |  | 872,626 |  |  | 866,595 |  |  | 6,031 |

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.
The underlying reasons for changes in our operating revenues for the three months ended March 31, 2025 compared to the same period in 2024 are presented below.

| Favorable (Unfavorable)
Changes in Operating Revenues (in millions) | Three Months Ended March 31, 2025 vs 2024 |  |
New rates from base rate proceedings, regulatory capital and DSM programs | $ | 82.1 |  |  |
The effects of weather in 2025 compared to 2024 | 28.2 |  |  |
The effects of customer usage | 3.8 |  |  |
The effects of customer growth | 3.4 |  |  |
Renewable JV revenue, fully offset by JV operating expense and noncontrolling interest net income (loss) | (4.1) |  |  |
Other | (0.1) |  |  |
Change in operating revenues (before cost of energy and other tracked items) | $ | 113.3 |  |  |
Operating revenues offset in operating expense |  |  |
Higher cost of energy billed to customers | 71.5 |  |  |
Higher tracker deferrals within operation and maintenance, depreciation and tax | 4.2 |  |  |
Total change in operating revenues | $ | 189.0 |  |  |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
NIPSCO Operations
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 weather normalization mechanisms. 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 March 31, 2025 compared to the same period in 2024 was primarily attributable to increased residential and industrial usage.
The increase in total volumes sold to gas customers for the three months ended March 31, 2025 compared to the same period in 2024 was primarily attributable to increases for residential and commercial customers 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 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 months ended March 31, 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.
NIPSCO Operations

| Favorable (Unfavorable)
Changes in Operating Expenses (in millions) | Three Months Ended March 31, 2025 vs 2024 |  |
Higher depreciation and amortization expense driven by new base rates | $ | (9.2) |  |  |
Higher outside services expenses | (4.0) |  |  |
Higher environmental remediation costs | (2.5) |  |  |
Higher employee and administrative expenses | (2.0) |  |  |
Other | (1.0) |  |  |
Change in operating expenses (before cost of energy and other tracked items) | $ | (18.7) |  |  |
Operating expenses offset in operating revenue |  |  |
Higher cost of energy billed to customers | (71.5) |  |  |
Higher tracker deferrals within operation and maintenance, depreciation and tax | (3.3) |  |  |
Total change in operating expense | $ | (93.5) |  |  |

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, which 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 evaluating the impacts of federal and state executive orders on its generation transition plans.
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. 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 will have an associated nameplate capacity, and payments under the PPAs will not begin until the associated generation facility is constructed by the owner/seller. NIPSCO has also executed several BTAs with developers to construct renewable generation facilities.
Since 2020, two wind PPA projects and six owned projects (two wind, two solar and two solar plus storage) have been placed into service totaling 2,201 MW of nameplate capacity, including Dunns Bridge II which was placed into service in January 2025. See "Executive Summary - Energy Transition" in this Management's Discussion for additional information. We expect the majority of our remaining BTA and PPA projects to be placed in service between 2025 and 2027.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
NIPSCO Operations

Remaining Renewables Projects | Transaction Type | Technology | Nameplate Capacity (MW) | Storage Capacity (MW) |  |  |
Fairbanks | BTA | Solar | 250 | — |  |  |
Gibson | BTA | Solar | 200 | — |  |  |
Templeton | BTA(1) | Wind | 200 | — |  |  |
Appleseed | 20 year PPA | Solar | 200 | — |  |  |
Green River | 20 year PPA | Solar | 200 | — |  |  |
Carpenter | 20 year PPA | Wind | 200 | — |  |  |

(1) Pending regulatory approval.
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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. Sources of financing activities for the quarter ended March 31, 2025 are as follows:
ATM program
•As of December 31, 2024 the ATM program had approximately $297.7 million of equity available for issuance through December 31, 2025.
◦In February 2025, we executed a forward sale agreement, which allows 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 March 2025, we executed a forward sale agreement, which allows 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.
◦As of March 31, 2025, the ATM program (inclusive of the forward sale agreements) had approximately $147.5 million of equity available for issuance.
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.
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:

| Three Months Ended March 31,
(in millions) | 2025 |  | 2024 |  | Change in 2025 vs 2024
Cash from (used for): |  |  |  |  |
Operating Activities | $ | 686.4 |  |  | $ | 456.2 |  |  | $ | 230.2 |
Investing Activities | (1,352.7) |  |  | (723.0) |  |  | (629.7) |
Financing Activities | 771.4 |  |  | (1,873.8) |  |  | 2,645.2 |

Operating Activities
The increase in cash from operating activities was primarily driven by year over year change in exchange gas receivables, higher net income, accounts payable, prepayments and other current assets, partially offset by higher accounts receivables due to colder weather.
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.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
We remain on track to make capital investments totaling $4.0 billion to $4.3 billion during the 2025 period. We also expect to invest approximately $19.4 billion during the 2025-2029 period, including capital investments to support our generation transition strategy. These forecasted capital investments are subject to continuing review and adjustment. Actual capital expenditures may vary from these estimates.
Regulatory Capital Programs. We are in the process of upgrading and modernizing 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 all six 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 - 2024 | $ | 763.3 |  | 4/21-12/23 | 2/26/2024 | 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 - 2024 | $ | 81.9 |  | 1/23-12/24 | 10/13/2023 | Replacement of mains and inclusion of system safety investments. |
NIPSCO - Electric(2) | TDSIC - 5 | $ | 346.9 |  | 7/22-3/24 | 5/28/2024 | New or replacement projects undertaken for the purpose of safety, reliability, system modernization or economic development. |
NIPSCO - Electric(2) | TDSIC - 6 | $ | 555.0 |  | 7/22-9/24 | 11/26/2024 | New or replacement projects undertaken for the purpose of safety, reliability, system modernization or economic development. |
NIPSCO - Electric(3) | GCT - 1 | $ | 149.4 |  | 9/23-10/25 | 12/16/2024 | New gas peaker generation project costs forecasted through Oct. 2025. |
NIPSCO - Gas(4) | TDSIC - 8 | $ | 8.3 |  | 1/23-2/24 | 4/30/2024 | New or replacement projects undertaken for the purpose of safety, reliability, system modernization or economic development. |
NIPSCO - Gas(4) | FMCA - 3 | $ | 27.0 |  | 1/23-6/24 | 8/27/2024 | Project costs to comply with federal mandates. |
Pending Commission Approval |
Columbia of Kentucky(5) | SMRP - 2025 | $ | 128.5 |  | 1/23-12/25 | 10/15/2024 | Replacement of mains and inclusion of system safety investments. |
NIPSCO - Gas | FMCA - 4 | $ | 9.4 |  | 6/24-12/24 | 2/25/2025 | Project costs to comply with federal mandates. |
Columbia of Ohio | CEP - 2025 | $ | 1,030.0 |  | 4/21-12/24 | 2/27/2025 | Assets not included in the IRP or PHMSA IRP. |

(1)Programs do not include any costs already included in base rates.
(2)TDSIC-5 was effective October 2024 through March 2025. An order was received for TDSIC-6 on March 26, 2025, and billing began in April 2025.
(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.
(4)The capital investment remaining after the Step 2 Compliance Filing, on February 13, 2025, is $5.8 million for TDSIC-8 and $2.3 million for FMCA-3.
(5)Rates went into effect January 2, 2025, subject to refund.
NIPSCO Gas filed a 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.
Financing Activities
Common Stock. Refer to Note 6, "Equity," in the Notes to the Condensed Consolidated Financial Statements (unaudited) for information on common stock.
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
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.
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 March 31, 2025 and December 31, 2024:

(in millions) | March 31, 2025 | December 31, 2024
Current Liquidity |  |
Revolving Credit Facility | $ | 1,850.0 |  | $ | 1,850.0 |
Accounts Receivable Programs(1) | 375.0 |  | 175.0 |
Less: |  |
Commercial Paper | 521.0 |  | 604.6 |
Accounts Receivable Programs Utilized | 250.0 |  | — |
Letters of Credit Outstanding Under Credit Facility | 0.5 |  | 9.4 |
Add: |  |
Cash and Cash Equivalents | 259.4 |  | 156.6 |
Net Available Liquidity | $ | 1,712.9 |  | $ | 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 March 31, 2025, the ratio was 53.8%.
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 March 31, 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 March 31, 2025, the collateral requirement that would be required in the event of a downgrade below the ratings trigger levels would amount to approximately $146.1 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 March 31, 2025, 470,618,280 shares of common stock were outstanding and no 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. Except for our March 2025 debt issuance, there were no additional material changes from year-end during the three months ended March 31, 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.
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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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
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 also received approval and 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) | None specified | $ | 40.5 |  | $ | 25.8 |  | April 29, 2022 | October 2022
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) | 9.80 | % | $ | 291.8 |  | $ | 261.9 |  | September 19, 2022 | August 2023
Pending Rate Cases |  |  |  |  |
NIPSCO - Electric(5) | In process | $ | 368.7 |  | In process | September 12, 2024 | September 2025
Columbia of Virginia(6) | In process | $ | 37.2 |  | In process | April 29, 2024 | October 2024
Columbia of Pennsylvania | 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 9.70% 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 2 steps, with implementation of Step 1 rates effective in August 2023 and Step 2 rates effective in March 2024.
(5)On February 7, 2025, NIPSCO and certain intervening parties filed a Joint Stipulation and Settlement Agreement with the IURC reflecting an annual revenue increase of $257.0 million. New rates proposed to be implemented in 2 steps, with implementation of Step 1 rates effective no later than September 2025 and Step 2 rates to be effective no later than March 2026.
(6)Rates are effective on an as filed basis and subject to refund. Columbia of Virginia and certain intervening parties, filed a Joint Stipulation and Proposed Recommendation for settlement on December 5, 2024, for an annual revenue increase of $28.2 million, net of SAVE. A hearing examiner’s report was received on February 27, 2025 recommending the adoption of Joint Stipulation and Proposed Recommendation without modification.
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. Specific areas of focus for upcoming rulemaking include 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.
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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
We continue to evaluate and monitor PHMSA legislation and regulations but cannot predict the impact of changing pipeline safety regulations on our business at this time.
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. 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.
Regarding federal policies, we continue to monitor the status of climate change-related legislation and regulation, including the IIJA and IRA and the potential forthcoming budget reconciliation legislation from Congress in 2025. We have identified and pursued potential opportunities associated with the IIJA and the IRA that align with our strategy. These opportunities include tax incentives for renewable generation and storage projects, tax credit transferability and grant funding for grid resiliency, hydrogen hubs and leak detection. The new federal administration has signaled through executive actions a desire to roll-back several climate-related policies including funding for IIJA and IRA programs. We continue to evaluate and monitor how these changes will impact our business.
In May 2024, the EPA published final GHG standards and guidelines for fossil fuel-fired power plants. The rules are not expected to impact NIPSCO’s existing electric generation, but, depending on the outcome of ongoing litigation and potential future changes to the rules, may impose certain operational limitations on other existing and new electric generation. Through the 2024 NIPSCO IRP process, we assessed that cost to electric customers would be approximately $675 million greater due to these rules.
We also continue to monitor evolving state policies related to GHG emissions. 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 updated 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. Columbia of Maryland is advocating for compliance pathways that use RNG, hydrogen, new technologies and emissions offsets. 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. Separately, the PSC has also initiated a proceeding related to Near-Term, Priority Actions and Comprehensive, Long-Term Planning for Maryland's Gas Companies. 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.
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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
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 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 signification 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 as of March 31, 2025 and December 31, 2024.
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 $2.5 million for the three months ended March 31, 2025 and $2.6 million for the three months ended March 31, 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
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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS (continued)
NiSource Inc.
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 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 March 31, 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 to provide reasonable assurance that financial information was processed, recorded and reported accurately.
Changes in Internal Controls
There have been no changes in our internal control over financial reporting during the most recently completed quarter covered by this report that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.
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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. There have been no material changes to such risk factors.
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
Director and Officer Trading Arrangements
During the quarter ended March 31, 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.

(4.4) | Form of 5.850% Notes due 2055 (incorporated by reference to Exhibit 4.1 to the NiSource Inc. Form 8-K filed on March 27, 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: | May 7, 2025 | By: | /s/ Gunnar J. Gode
|  |  | Gunnar J. Gode
|  |  | Vice President, Chief Accounting Officer (Principal Accounting Officer)

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