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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 JUNE 30, 2025
OR
☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
Commission file number 1-7933
Aon plc
(Exact Name of Registrant as Specified in Its Charter)

IRELAND |  | 98-1539969
(State or other jurisdiction of |  | (I.R.S. Employer
incorporation or organization) |  | Identification No.)

15 George's Quay, Dublin 2, Ireland |  | D02 VR98
(Address of principal executive offices) |  | (Zip Code)

+353 1 266 6000
(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
Class A Ordinary Shares $0.01 nominal value |  | AON |  | New York Stock Exchange
Guarantees of Aon plc’s 3.875% Senior Notes due 2025 |  | AON25 |  | New York Stock Exchange
Guarantees of Aon plc’s 2.875% Senior Notes due 2026 |  | AON26 |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.85% Senior Notes due 2027 |  | AON27 |  | New York Stock Exchange
Guarantees of Aon North America, Inc.’s 5.125% Senior Notes due 2027 |  | AON27B |  | New York Stock Exchange
Guarantees of Aon North America, Inc.’s 5.150% Senior Notes due 2029 |  | AON29 |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.05% Senior Notes due 2031 |  | AON31 |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.60% Senior Notes due 2031 |  | AON31A |  | New York Stock Exchange
Guarantees of Aon North America, Inc.’s 5.300% Senior Notes due 2031 |  | AON31B |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 5.00% Senior Notes due 2032 |  | AON32 |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 5.35% Senior Notes due 2033 |  | AON33 |  | New York Stock Exchange
Guarantees of Aon North America, Inc.’s 5.450% Senior Notes due 2034 |  | AON34 |  | New York Stock Exchange
Guarantees of Aon plc’s 4.25% Senior Notes due 2042 |  | AON42 |  | New York Stock Exchange
Guarantees of Aon plc’s 4.45% Senior Notes due 2043 |  | AON43 |  | New York Stock Exchange
Guarantees of Aon plc’s 4.60% Senior Notes due 2044 |  | AON44 |  | New York Stock Exchange
Guarantees of Aon plc’s 4.75% Senior Notes due 2045 |  | AON45 |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.90% Senior Notes due 2051 |  | AON51 |  | New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 3.90% Senior Notes due 2052 |  | AON52 |  | New York Stock Exchange
Guarantees of Aon North America, Inc.’s 5.750% Senior Notes due 2054 |  | AON54 |  | New York Stock Exchange

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 ☒ 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 ☒ 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 | ☒ |  | Accelerated filer | ☐ |
Non-accelerated filer | ☐ |  | Smaller reporting company | ☐ |
|  |  | Emerging growth 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 ☒
Number of class A ordinary shares of Aon plc, $0.01 nominal value, outstanding as of July 24, 2025: 215,626,597

INFORMATION CONCERNING FORWARD-LOOKING STATEMENTS
This report contains certain statements related to future results, or states our intentions, beliefs, and expectations or predictions for the future, all of which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995, 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”). Forward-looking statements represent management’s expectations or forecasts of future events. These statements include statements about our plans, objectives, strategies, financial performance and outlook, trends, prospects or other future events and involve known and unknown risks that are difficult to predict. Forward-looking statements are typically identified by words such as “anticipate,” “believe,” “estimate,” “expect,” “forecast,” “project,” “positioned,” “intend,” “plan,” “probably,” “potential,” “looking forward,” “continue,” and other similar terms, and future or conditional tense verbs like “could,” “may,” “might,” “should,” “will,” and “would.” You can also identify forward-looking statements by the fact that they do not relate strictly to historical or current facts. For example, we may use forward-looking statements when addressing topics such as: market and industry conditions, including competitive and pricing trends; changes in our business strategies and methods of generating revenue; the development and performance of our services and products; changes in the composition or level of our revenues; our cost structure and the outcome of cost-saving or restructuring initiatives, including the impacts of the Accelerating Aon United Program; the outcome of contingencies; dividend policy; the expected impact of acquisitions, dispositions, and other significant transactions or the termination thereof; litigation and regulatory matters; pension obligations; cash flow and liquidity; expected effective tax rate; expected foreign currency translation impacts; potential changes in laws or future actions by regulators; and the impact of changes in accounting rules. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results depending on a variety of factors. Potential factors, which may be revised or supplemented in subsequent reports filed or furnished with the Securities and Exchange Commission, that could impact results include:
•changes in the competitive environment, due to macroeconomic conditions or otherwise, or damage to our reputation;
•fluctuations in currency exchange, interest, or inflation rates that could impact our financial condition or results;
•changes in global equity and fixed income markets that could affect the return on invested assets;
•changes in the funded status of our various defined benefit pension plans and the impact of any increased pension funding resulting from those changes;
•the level of our debt and the terms thereof reducing our flexibility or increasing borrowing costs;
•rating agency actions that could limit our access to capital and our competitive position;
•our global tax rate being subject to a variety of different factors, including the adoption and implementation in the European Union, the United States, the United Kingdom, or other countries of the Organization for Economic Co-operation and Development tax proposals or other pending proposals in those and other countries, which could create volatility in that tax rate;
•changes in our accounting estimates and assumptions on our financial statements;
•limits on our subsidiaries’ ability to pay dividends or otherwise make payments to their respective parent entities;
•the impact of legal proceedings and other contingencies, including those arising from acquisition or disposition transactions, errors and omissions and other claims against us (including proceedings and contingencies relating to transactions for which capital was arranged by Vesttoo Ltd. or related to actions we may take in being responsible for making decisions on behalf of clients in our investment businesses or in other advisory services that we currently provide, or may provide in the future);
•the impact of, and potential challenges in complying with, laws and regulations of the jurisdictions in which we operate, particularly given the global nature of our operations and the possibility of differing or conflicting laws and regulations, or the application or interpretation thereof, across such jurisdictions;
•the impact of any regulatory investigations brought in Ireland, the United Kingdom, the United States, and other countries;
•failure to protect intellectual property rights or allegations that we have infringed on the intellectual property rights of others;
•general economic and political conditions in the countries in which we do business around the world;
3

•the failure to retain, attract and develop experienced and qualified personnel;
•international risks associated with our global operations, including geopolitical conflicts, tariffs, or changes in trade policies;
•the effects of natural or human-caused disasters, including the effects of health pandemics and the impacts of climate-related events;
•any system or network disruption or breach resulting in operational interruption or improper disclosure of confidential, personal, or proprietary data, and resulting liabilities or damage to our reputation;
•our ability to develop, implement, update, and enhance new technology;
•the actions taken by third parties that perform aspects of our business operations and client services;
•our ability to continue, and the costs and risks associated with growing, developing and integrating acquired business, and entering into new lines of business or products;
•our ability to secure regulatory approval and complete transactions, and the costs and risks associated with the failure to consummate proposed transactions;
•changes in commercial property and casualty markets, commercial premium rates or methods of compensation;
•our ability to develop and implement innovative growth strategies and initiatives intended to yield cost savings (including the Accelerating Aon United Program) and the ability to achieve such growth or cost savings;
•the effects of Irish law on our operating flexibility and the enforcement of judgments against us;
•adverse effects on the market price of Aon’s securities and/or operating results for any reason, including, without limitation, because of a failure to realize the expected be nefits of the acquisition of NFP (including anticipated revenue and growth synergies) in the expected timeframe, or at all; and
•significant integration costs in connection with the acquisition of NFP or unknown or inestimable liabilities.
Any or all of our forward-looking statements may turn out to be inaccurate, and there are no guarantees about our performance. The factors identified above are not exhaustive. Aon and its subsidiaries operate in a dynamic business environment in which new risks may emerge frequently. Accordingly, readers should not place undue reliance on forward-looking statements, which speak only as of the dates on which they are made. We are under no (and expressly disclaim any) obligation to update or alter any forward-looking statement that we may make from time to time, whether as a result of new information, future events, or otherwise.
Further information about factors that could materially affect Aon, including our results of operations and financial condition, is contained in our filings with the SEC, including the “Risk Factors” section in Part I, Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2024. These factors may be revised or supplemented in our subsequent periodic filings with the SEC.
4

Table of Contents

PART I - FINANCIAL INFORMATION
| Item 1. Financial Statements
| Aon plc Condensed Consolidated Statements of Income
| Aon plc Condensed Consolidated Statements of Comprehensive Income
| Aon plc Condensed Consolidated Statements of Financial Position
| Aon plc Condensed Consolidated Statements of Shareholders’ Equity
| Aon plc Condensed Consolidated Statements of Cash Flows
| Notes to Condensed Consolidated Financial Statements
| Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations
| Item 3. Quantitative and Qualitative Disclosures about Market Risk
| Item 4. Controls and Procedures
PART II - OTHER INFORMATION
| Item 1. Legal Proceedings
| Item 1A. Risk Factors
| Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
| Item 3. Defaults Upon Senior Securities
| Item 4. Mine Safety Disclosures
| Item 5. Other Information
| Item 6. Exhibits
| Signature
| Exhibit Index

5

The below definitions apply throughout this report unless the context requires otherwise:

Term | Definition
AAU | Accelerating Aon United Program
ASC | Accounting Standards Codification
CODM | Chief Operating Decision Maker
DCF | Discounted Cash Flow
E&O | Errors and Omissions
EBITDA | Earnings before Interest, Taxes, Depreciation, and Amortization
EMEA | Europe, the Middle East, and Africa
ESG | Environmental, Social, and Governance
E.U. | European Union
FASB | Financial Accounting Standards Board
FCA | Financial Conduct Authority
GAAP | U.S. Generally Accepted Accounting Principles
GHG | Greenhouse Gas
LOC | Letter of Credit
OECD | Organization for Economic Co-operation and Development
P&C | Property and Casualty
ROU | Right-of-Use
SEC | Securities and Exchange Commission
U.K. | United Kingdom
U.S. | United States
VIE | Variable Interest Entity

6

Part I Financial Information
Item 1. Financial Statements
Aon plc
Condensed Consolidated Statements of Income
(Unaudited)

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
(millions, except per share data) |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue |  |  |  |  |  |  |  |
Total revenue |  | $ | 4,155 |  |  | $ | 3,760 |  |  | $ | 8,884 |  |  | $ | 7,830 |
Expenses |  |  |  |  |  |  |  |
Compensation and benefits |  | 2,360 |  |  | 2,130 |  |  | 4,609 |  |  | 4,013 |
Information technology |  | 136 |  |  | 132 |  |  | 272 |  |  | 256 |
Premises |  | 85 |  |  | 82 |  |  | 167 |  |  | 153 |
Depreciation of fixed assets |  | 47 |  |  | 45 |  |  | 93 |  |  | 89 |
Amortization and impairment of intangible assets |  | 201 |  |  | 128 |  |  | 400 |  |  | 144 |
Other general expense |  | 373 |  |  | 455 |  |  | 819 |  |  | 803 |
Accelerating Aon United Program expenses |  | 94 |  |  | 132 |  |  | 204 |  |  | 251 |
Total operating expenses |  | 3,296 |  |  | 3,104 |  |  | 6,564 |  |  | 5,709 |
Operating income |  | 859 |  |  | 656 |  |  | 2,320 |  |  | 2,121 |
Interest income |  | — |  |  | 31 |  |  | 5 |  |  | 59 |
Interest expense |  | (212) |  |  | (225) |  |  | (418) |  |  | (369) |
Other income (expense) |  | 56 |  |  | 236 |  |  | 46 |  |  | 311 |
Income before income taxes |  | 703 |  |  | 698 |  |  | 1,953 |  |  | 2,122 |
Income tax expense |  | 109 |  |  | 160 |  |  | 377 |  |  | 491 |
Net income |  | 594 |  |  | 538 |  |  | 1,576 |  |  | 1,631 |
Less: Net income attributable to redeemable and nonredeemable noncontrolling interests |  | 15 |  |  | 14 |  |  | 32 |  |  | 36 |
Net income attributable to Aon shareholders |  | $ | 579 |  |  | $ | 524 |  |  | $ | 1,544 |  |  | $ | 1,595 |
Basic net income per share attributable to Aon shareholders |  | $ | 2.68 |  |  | $ | 2.47 |  |  | $ | 7.14 |  |  | $ | 7.75 |
Diluted net income per share attributable to Aon shareholders |  | $ | 2.66 |  |  | $ | 2.46 |  |  | $ | 7.10 |  |  | $ | 7.72 |
Weighted average ordinary shares outstanding - basic |  | 216.2 |  |  | 212.5 |  |  | 216.3 |  |  | 205.8 |
Weighted average ordinary shares outstanding - diluted |  | 217.3 |  |  | 213.3 |  |  | 217.6 |  |  | 206.7 |

See accompanying Notes to Condensed Consolidated Financial Statements (Unaudited).
7

Aon plc
Condensed Consolidated Statements of Comprehensive Income
(Unaudited)

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
(millions) |  | 2025 |  | 2024 |  | 2025 |  | 2024
Net income |  | $ | 594 |  |  | $ | 538 |  |  | $ | 1,576 |  |  | $ | 1,631 |
Less: Net income attributable to redeemable and nonredeemable noncontrolling interests |  | 15 |  |  | 14 |  |  | 32 |  |  | 36 |
Net income attributable to Aon shareholders |  | 579 |  |  | 524 |  |  | 1,544 |  |  | 1,595 |
Other comprehensive income (loss), net of tax: |  |  |  |  |  |  |  |
Change in fair value of financial instruments |  | 10 |  |  | 1 |  |  | 13 |  |  | 76 |
Foreign currency translation adjustments |  | 604 |  |  | (88) |  |  | 843 |  |  | (220) |
Postretirement benefit obligation |  | (1) |  |  | 13 |  |  | 46 |  |  | 39 |
Total other comprehensive income (loss) |  | 613 |  |  | (74) |  |  | 902 |  |  | (105) |
Less: Other comprehensive income attributable to noncontrolling interests |  | — |  |  | — |  |  | — |  |  | — |
Total other comprehensive income (loss) attributable to Aon shareholders |  | 613 |  |  | (74) |  |  | 902 |  |  | (105) |
Comprehensive income attributable to Aon shareholders |  | $ | 1,192 |  |  | $ | 450 |  |  | $ | 2,446 |  |  | $ | 1,490 |

See accompanying Notes to Condensed Consolidated Financial Statements (Unaudited).
8

Aon plc
Condensed Consolidated Statements of Financial Position

|  | (Unaudited) |  |
(millions, except nominal value) |  | June 30, 2025 |  | December 31, 2024
Assets |  |  |  |
Current assets |  |  |  |
Cash and cash equivalents |  | $ | 1,008 |  |  | $ | 1,085 |
Short-term investments |  | 379 |  |  | 219 |
Receivables, net |  | 4,905 |  |  | 3,803 |
Fiduciary assets |  | 20,677 |  |  | 17,566 |
Other current assets |  | 854 |  |  | 759 |
Total current assets |  | 27,823 |  |  | 23,432 |
Goodwill |  | 16,024 |  |  | 15,234 |
Intangible assets, net |  | 6,733 |  |  | 6,743 |
Fixed assets, net |  | 664 |  |  | 637 |
Operating lease right-of-use assets |  | 735 |  |  | 711 |
Deferred tax assets |  | 861 |  |  | 654 |
Prepaid pension |  | 598 |  |  | 556 |
Other non-current assets |  | 572 |  |  | 998 |
Total assets |  | $ | 54,010 |  |  | $ | 48,965 |
Liabilities, redeemable noncontrolling interests, and equity |  |  |  |
Liabilities |  |  |  |
Current liabilities |  |  |  |
Accounts payable and accrued liabilities |  | $ | 2,294 |  |  | $ | 2,905 |
Short-term debt and current portion of long-term debt |  | 1,837 |  |  | 751 |
Fiduciary liabilities |  | 20,677 |  |  | 17,566 |
Other current liabilities |  | 2,267 |  |  | 1,773 |
Total current liabilities |  | 27,075 |  |  | 22,995 |
Long-term debt |  | 15,451 |  |  | 16,265 |
Non-current operating lease liabilities |  | 705 |  |  | 685 |
Deferred tax liabilities |  | 363 |  |  | 319 |
Pension, other postretirement, and postemployment liabilities |  | 1,078 |  |  | 1,127 |
Other non-current liabilities |  | 1,249 |  |  | 1,144 |
Total liabilities |  | 45,921 |  |  | 42,535 |
Redeemable noncontrolling interests |  | 81 |  |  | 125 |
Equity |  |  |  |
Ordinary shares - $0.01 nominal value Authorized: 500.0 shares (issued: 2025 - 215.7; 2024 - 216.0) |  | 2 |  |  | 2 |
Additional paid-in capital |  | 13,258 |  |  | 13,173 |
Accumulated deficit |  | (1,574) |  |  | (2,309) |
Accumulated other comprehensive loss |  | (3,843) |  |  | (4,745) |
Total Aon shareholders' equity |  | 7,843 |  |  | 6,121 |
Nonredeemable noncontrolling interests |  | 165 |  |  | 184 |
Total equity |  | 8,008 |  |  | 6,305 |
Total liabilities, redeemable noncontrolling interests and equity |  | $ | 54,010 |  |  | $ | 48,965 |

See accompanying Notes to Condensed Consolidated Financial Statements (Unaudited).
9

Aon plc
Condensed Consolidated Statements of Shareholders’ Equity
(Unaudited)

(millions) |  | Shares |  | Ordinary Shares and Additional Paid-in Capital |  | Accumulated Deficit |  | Accumulated Other Comprehensive Loss, Net of Tax |  | Non- redeemable Non- controlling Interests |  | Total
Balance at January 1, 2025 |  | 216.0 |  |  | $ | 13,175 |  |  | $ | (2,309) |  |  | $ | (4,745) |  |  | $ | 184 |  |  | $ | 6,305 |
Net income (1) |  | — |  |  | — |  |  | 965 |  |  | — |  |  | 21 |  |  | 986 |
Shares issued - employee stock compensation plans |  | 0.7 |  |  | (111) |  |  | — |  |  | — |  |  | — |  |  | (111) |
Shares repurchased |  | (0.6) |  |  | — |  |  | (250) |  |  | — |  |  | — |  |  | (250) |
Share-based compensation expense |  | — |  |  | 147 |  |  | — |  |  | — |  |  | — |  |  | 147 |
Dividends to shareholders ($0.675 per share) |  | — |  |  | — |  |  | (146) |  |  | — |  |  | — |  |  | (146) |
Net change in fair value of financial instruments |  | — |  |  | — |  |  | — |  |  | 3 |  |  | — |  |  | 3 |
Net foreign currency translation adjustments |  | — |  |  | — |  |  | — |  |  | 239 |  |  | — |  |  | 239 |
Net postretirement benefit obligation |  | — |  |  | — |  |  | — |  |  | 47 |  |  | — |  |  | 47 |
Dividends paid to nonredeemable noncontrolling interests on subsidiary common stock |  | — |  |  | — |  |  | — |  |  | — |  |  | (14) |  |  | (14) |
Remeasurement of redemption value of redeemable noncontrolling interest |  | — |  |  | (11) |  |  | — |  |  | — |  |  | — |  |  | (11) |
Balance at March 31, 2025 |  | 216.1 |  |  | $ | 13,200 |  |  | $ | (1,740) |  |  | $ | (4,456) |  |  | $ | 191 |  |  | $ | 7,195 |
Net income (2) |  | — |  |  | — |  |  | 579 |  |  | — |  |  | 14 |  |  | 593 |
Shares issued - employee stock compensation plans |  | 0.3 |  |  | (49) |  |  | (1) |  |  | — |  |  | — |  |  | (50) |
Shares repurchased |  | (0.7) |  |  | — |  |  | (250) |  |  | — |  |  | — |  |  | (250) |
Share-based compensation expense |  | — |  |  | 119 |  |  | — |  |  | — |  |  | — |  |  | 119 |
Dividends to shareholders ($0.745 per share) |  | — |  |  | — |  |  | (162) |  |  | — |  |  | — |  |  | (162) |
Net change in fair value of financial instruments |  | — |  |  | — |  |  | — |  |  | 10 |  |  | — |  |  | 10 |
Net foreign currency translation adjustments |  | — |  |  | — |  |  | — |  |  | 604 |  |  | — |  |  | 604 |
Net postretirement benefit obligation |  | — |  |  | — |  |  | — |  |  | (1) |  |  | — |  |  | (1) |
Purchases of subsidiary shares from nonredeemable noncontrolling interests |  | — |  |  | (9) |  |  | — |  |  | — |  |  | — |  |  | (9) |
Dividends paid to nonredeemable noncontrolling interests on subsidiary common stock |  | — |  |  | — |  |  | — |  |  | — |  |  | (40) |  |  | (40) |
Remeasurement of redemption value of redeemable noncontrolling interest |  | — |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | (1) |
Balance at June 30, 2025 |  | 215.7 |  |  | $ | 13,260 |  |  | $ | (1,574) |  |  | $ | (3,843) |  |  | $ | 165 |  |  | $ | 8,008 |

(1)The Company’s Net income totaled $982 million for the quarter ended March 31, 2025, which included $4 million of Net loss related to redeemable noncontrolling interests.
(2)The Company’s Net income totaled $594 million for the quarter ended June 30, 2025, which included $1 million of Net gain related to redeemable noncontrolling interests.
10

(millions) |  | Shares |  | Ordinary Shares and Additional Paid-in Capital |  | Accumulated Deficit |  | Accumulated Other Comprehensive Loss, Net of Tax |  | Non-redeemable Non- controlling Interests |  | Total
Balance at January 1, 2024 |  | 198.6 |  |  | $ | 6,946 |  |  | $ | (3,399) |  |  | $ | (4,373) |  |  | $ | 84 |  |  | $ | (742) |
Net income |  | — |  |  | — |  |  | 1,071 |  |  | — |  |  | 22 |  |  | 1,093 |
Shares issued - employee stock compensation plans |  | 0.8 |  |  | (104) |  |  | — |  |  | — |  |  | — |  |  | (104) |
Shares repurchased |  | (0.8) |  |  | — |  |  | (250) |  |  | — |  |  | — |  |  | (250) |
Share-based compensation expense |  | — |  |  | 130 |  |  | — |  |  | — |  |  | — |  |  | 130 |
Dividends to shareholders ($0.615 per share) |  | — |  |  | — |  |  | (122) |  |  | — |  |  | — |  |  | (122) |
Net change in fair value of financial instruments |  | — |  |  | — |  |  | — |  |  | 75 |  |  | — |  |  | 75 |
Net foreign currency translation adjustments |  | — |  |  | — |  |  | — |  |  | (132) |  |  | — |  |  | (132) |
Net postretirement benefit obligation |  | — |  |  | — |  |  | — |  |  | 26 |  |  | — |  |  | 26 |
Purchases of subsidiary shares from nonredeemable noncontrolling interests |  | — |  |  | (1) |  |  | — |  |  | — |  |  | — |  |  | (1) |
Dividends paid to nonredeemable noncontrolling interests on subsidiary common stock |  | — |  |  | — |  |  | — |  |  | — |  |  | (1) |  |  | (1) |
Balance at March 31, 2024 |  | 198.6 |  |  | $ | 6,971 |  |  | $ | (2,700) |  |  | $ | (4,404) |  |  | $ | 105 |  |  | $ | (28) |
Net income (1) |  | — |  |  | — |  |  | 524 |  |  | — |  |  | 12 |  |  | 536 |
Shares issued - NFP Transaction |  | 19.0 |  |  | 5,882 |  |  | — |  |  | — |  |  | — |  |  | 5,882 |
Shares issued - employee stock compensation plans |  | 0.4 |  |  | (45) |  |  | — |  |  | — |  |  | — |  |  | (45) |
Shares repurchased |  | (0.8) |  |  | — |  |  | (250) |  |  | — |  |  | — |  |  | (250) |
Share-based compensation expense |  | — |  |  | 117 |  |  | — |  |  | — |  |  | — |  |  | 117 |
Dividends to shareholders ($0.675 per share) |  | — |  |  | — |  |  | (148) |  |  | — |  |  | — |  |  | (148) |
Net change in fair value of financial instruments |  | — |  |  | — |  |  | — |  |  | 1 |  |  | — |  |  | 1 |
Net foreign currency translation adjustments |  | — |  |  | — |  |  | — |  |  | (88) |  |  | — |  |  | (88) |
Net postretirement benefit obligation |  | — |  |  | — |  |  | — |  |  | 13 |  |  | — |  |  | 13 |
Purchases of subsidiary shares from nonredeemable noncontrolling interests |  | — |  |  | — |  |  | — |  |  | — |  |  | 86 |  |  | 86 |
Dividends paid to nonredeemable noncontrolling interests on subsidiary common stock |  | — |  |  | — |  |  | — |  |  | — |  |  | (35) |  |  | (35) |
Adjustments to redeemable noncontrolling interests |  | — |  |  | (13) |  |  | — |  |  | — |  |  | — |  |  | (13) |
Balance at June 30, 2024 |  | 217.2 |  |  | $ | 12,912 |  |  | $ | (2,574) |  |  | $ | (4,478) |  |  | $ | 168 |  |  | $ | 6,028 |

(1)The Company’s Net income totaled $538 million for the quarter ended June 30, 2024, which included $2 million of Net income related to redeemable noncontrolling interests.
See accompanying Notes to Condensed Consolidated Financial Statements (Unaudited).
11

Aon plc
Condensed Consolidated Statements of Cash Flows
(Unaudited)

|  | Six Months Ended June 30,
(millions) |  | 2025 |  | 2024
Cash flows from operating activities |  |  |  |
Net income |  | $ | 1,576 |  |  | $ | 1,631 |
Adjustments to reconcile net income to cash provided by operating activities: |  |  |  |
Gain from sales of businesses |  | — |  |  | (257) |
Depreciation of fixed assets |  | 93 |  |  | 89 |
Amortization and impairment of intangible assets |  | 400 |  |  | 144 |
Share-based compensation expense |  | 266 |  |  | 247 |
Deferred income taxes |  | (242) |  |  | (122) |
Other, net |  | (111) |  |  | (112) |
Change in assets and liabilities: |  |  |  |
Receivables, net |  | (902) |  |  | (959) |
Accounts payable and accrued liabilities |  | (738) |  |  | (251) |
Accelerating Aon United Program liabilities |  | 15 |  |  | 61 |
Current income taxes |  | (73) |  |  | 60 |
Pension, other postretirement and postemployment liabilities |  | (12) |  |  | (17) |
Other assets and liabilities |  | 664 |  |  | 308 |
Cash provided by operating activities |  | 936 |  |  | 822 |
Cash flows from investing activities |  |  |  |
Proceeds from investments |  | 71 |  |  | 146 |
Purchases of investments |  | (42) |  |  | (91) |
Net purchases (sales) of short-term investments - non fiduciary |  | (153) |  |  | 189 |
Acquisition of businesses, net of cash and funds held on behalf of clients |  | (143) |  |  | (2,780) |
Sale of businesses, net of cash and funds held on behalf of clients |  | 119 |  |  | 352 |
Capital expenditures |  | (120) |  |  | (101) |
Cash used for investing activities |  | (268) |  |  | (2,285) |
Cash flows from financing activities |  |  |  |
Share repurchase |  | (500) |  |  | (500) |
Proceeds from issuance of shares |  | 33 |  |  | 27 |
Cash paid for employee taxes on withholding shares |  | (194) |  |  | (176) |
Commercial paper issuances, net of repayments |  | 480 |  |  | (591) |
Issuance of debt |  | — |  |  | 7,926 |
Repayment of debt |  | (300) |  |  | (4,328) |
Increase in fiduciary liabilities, net of fiduciary receivables |  | 569 |  |  | 283 |
Cash dividends to shareholders |  | (308) |  |  | (269) |
Redeemable and nonredeemable noncontrolling interests, and other financing activities |  | (153) |  |  | (108) |
Cash provided by (used for) financing activities |  | (373) |  |  | 2,264 |
Effect of exchange rates on cash and cash equivalents and funds held on behalf of clients |  | 696 |  |  | (202) |
Net increase in cash and cash equivalents and funds held on behalf of clients |  | 991 |  |  | 599 |
Cash, cash equivalents and funds held on behalf of clients at beginning of period |  | 8,333 |  |  | 7,722 |
Cash, cash equivalents and funds held on behalf of clients at end of period |  | $ | 9,324 |  |  | $ | 8,321 |
Reconciliation of cash and cash equivalents and funds held on behalf of clients: |  |  |  |
Cash and cash equivalents |  | $ | 1,008 |  |  | $ | 974 |
Cash and cash equivalents and funds held on behalf of clients classified as held for sale |  | 1 |  |  | 38 |
Funds held on behalf of clients |  | 8,315 |  |  | 7,309 |
Total cash and cash equivalents and funds held on behalf of clients |  | $ | 9,324 |  |  | $ | 8,321 |
Supplemental disclosures: |  |  |  |
Interest paid |  | $ | 416 |  |  | $ | 256 |
Income taxes paid, net of refunds |  | $ | 692 |  |  | $ | 553 |

See accompanying Notes to Condensed Consolidated Financial Statements (Unaudited).
12

Notes to Condensed Consolidated Financial Statements (Unaudited)
1. Basis of Presentation
The accompanying Condensed Consolidated Financial Statements and Notes thereto have been prepared in accordance with U.S. GAAP. The Condensed Consolidated Financial Statements include the accounts of Aon plc and all of its controlled subsidiaries (“Aon” or the “Company”). Intercompany accounts and transactions have been eliminated. The Condensed Consolidated Financial Statements include, in the opinion of management, all adjustments (consisting of normal recurring adjustments and reclassifications) necessary to present fairly the Company’s consolidated financial position, results of operations, and cash flows for all periods presented.
Certain information and disclosures normally included in the Consolidated Financial Statements prepared in accordance with U.S. GAAP have been condensed or omitted. The Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024. The results for the three and six months ended June 30, 2025 are not necessarily indicative of operating results that may be expected for the full year ending December 31, 2025.
Use of Estimates
The preparation of the accompanying Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosures of contingent assets and liabilities at the date of the Condensed Consolidated Financial Statements, and the reported amounts of reserves and expenses. These estimates and assumptions are based on management’s best estimates and judgments. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment. Management believes its estimates to be reasonable given the current facts available. Aon adjusts such estimates and assumptions when facts and circumstances dictate. Illiquid credit markets, volatile equity markets, and foreign currency exchange rate movements increase the uncertainty inherent in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in estimates resulting from continuing changes in the economic environment would, if applicable, be reflected in the Condensed Consolidated Financial Statements in future periods.
2. Accounting Principles and Practices
New Accounting Pronouncements
Accounting Standards Issued But Not Yet Adopted
Improvements to Income Tax Disclosures
In December 2023, the FASB issued new accounting guidance under ASC 740, Income Taxes, which requires additional income tax disclosures on an annual basis, including disaggregation of information presented within the reconciliation of the expected tax to the reported tax by specific categories, with certain reconciling items 5% or greater broken out by nature and/or jurisdiction. The new guidance also requires disclosure of income taxes paid, net of refunds, broken out by federal, state/local and foreign, including disclosure of individual jurisdictions when greater than 5% of total net income taxes paid. The new guidance is effective for annual periods beginning the year ended December 31, 2025. The Company is evaluating the transition approach as well as the impact the disclosures will have on the Notes to Consolidated Financial Statements.
Disaggregation of Income Statement Expenses
In November 2024, the FASB issued new accounting guidance under ASC 220, Income Statement — Reporting Comprehensive Income, which requires more detailed information about certain expenses in commonly presented expense captions including inventory, employee compensation, depreciation, and amortization. The new guidance also requires disclosure of total selling expenses and, on an annual basis, an entity’s definition of selling expenses. The new guidance is effective for Aon for the year ended December 31, 2027, with early adoption permitted. Entities may apply the new guidance on a prospective basis, with the option for retrospective application. Aon is currently evaluating the transition approach and the impact the guidance will have on the Notes to Consolidated Financial Statements.
Securities and Exchange Commission Final Rules
The Enhancement and Standardization of Climate-Related Disclosures for Investors
In March 2024, the SEC adopted final rules to enhance and standardize climate-related disclosures. The final rules would require the Company to provide certain climate-related information in Item 7, Management’s Discussion and Analysis
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regarding material climate-related risks, activities to mitigate or adapt to such risks, information regarding oversight and management of climate-related risks, information on climate-related targets or goals, and disclosure of Scope 1 and 2 GHG emissions. Additionally, within the Notes to Consolidated Financial Statements, the Company would be required to disclose the financial statement effects of severe weather events and other natural conditions. The final rules were to be effective for Aon for the year ended December 31, 2025, with the exception of GHG emissions disclosures which were to be effective for Aon for the year ended December 31, 2026. The final rules have been subject to several legal challenges. On April 4, 2024, the SEC voluntarily stayed the final rules pending judicial review, and on March 27, 2025, the SEC voted to end its legal defense of the final rules in Court of Appeals for the Eighth Circuit. The Eighth Circuit subsequently suspended the litigation until the SEC informed the court about whether it intends to review or reconsider the rules under administrative procedures and whether the SEC would enforce the rules if ultimately upheld. On July 23, 2025, the SEC filed a status report in response, stating that it does not intend to review or reconsider the rules under administrative procedures, and declined to say whether or not it would enforce the rules if ultimately upheld. The Company is monitoring the judicial process for resolution of the legal challenges and impacts on the disclosure requirements.
3. Revenue from Contracts with Customers
Disaggregation of Revenue
The following table summarizes revenue from contracts with customers by principal service line (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Commercial Risk Solutions |  | $ | 2,178 |  |  | $ | 2,015 |  |  | $ | 4,180 |  |  | $ | 3,823 |
Reinsurance Solutions |  | 688 |  |  | 635 |  |  | 1,877 |  |  | 1,802 |
Total Risk Capital (1) |  | 2,866 |  |  | 2,650 |  |  | 6,057 |  |  | 5,625 |
Health Solutions |  | 772 |  |  | 662 |  |  | 1,798 |  |  | 1,395 |
Wealth Solutions |  | 519 |  |  | 463 |  |  | 1,038 |  |  | 833 |
Total Human Capital (1) |  | 1,291 |  |  | 1,125 |  |  | 2,836 |  |  | 2,228 |
Eliminations |  | (2) |  |  | (15) |  |  | (9) |  |  | (23) |
Total revenue |  | $ | 4,155 |  |  | $ | 3,760 |  |  | $ | 8,884 |  |  | $ | 7,830 |

(1)Includes inter-segment revenue. Refer to Note 16 “Segment Information” for further information.
Consolidated revenue from contracts with customers by geographic area, which is attributed on the basis of where the services are performed, is as follows (in millions):

|  | Three Months Ended June 30, 2025
|  | Risk Capital |  | Human Capital |  | Corporate/Eliminations |  | Total
U.S. |  | $ | 1,324 |  |  | $ | 718 |  |  | $ | (2) |  |  | $ | 2,040 |
Americas other than U.S. |  | 285 |  |  | 110 |  |  | — |  |  | 395 |
U.K. |  | 411 |  |  | 199 |  |  | — |  |  | 610 |
Ireland |  | 24 |  |  | 22 |  |  | — |  |  | 46 |
Europe, Middle East, & Africa other than U.K. and Ireland |  | 469 |  |  | 165 |  |  | — |  |  | 634 |
Asia Pacific |  | 353 |  |  | 77 |  |  | — |  |  | 430 |
Total revenue |  | $ | 2,866 |  |  | $ | 1,291 |  |  | $ | (2) |  |  | $ | 4,155 |

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|  | Three Months Ended June 30, 2024
|  | Risk Capital |  | Human Capital |  | Corporate/Eliminations |  | Total
U.S. |  | $ | 1,217 |  |  | $ | 635 |  |  | $ | (15) |  |  | $ | 1,837 |
Americas other than U.S. |  | 260 |  |  | 102 |  |  | — |  |  | 362 |
U.K. |  | 379 |  |  | 169 |  |  | — |  |  | 548 |
Ireland |  | 20 |  |  | 15 |  |  | — |  |  | 35 |
Europe, Middle East, & Africa other than U.K. and Ireland |  | 428 |  |  | 138 |  |  | — |  |  | 566 |
Asia Pacific |  | 346 |  |  | 66 |  |  | — |  |  | 412 |
Total revenue |  | $ | 2,650 |  |  | $ | 1,125 |  |  | $ | (15) |  |  | $ | 3,760 |

|  | Six Months Ended June 30, 2025
|  | Risk Capital |  | Human Capital |  | Corporate/Eliminations |  | Total
U.S. |  | $ | 2,545 |  |  | $ | 1,506 |  |  | $ | (9) |  |  | $ | 4,042 |
Americas other than U.S. |  | 539 |  |  | 230 |  |  | — |  |  | 769 |
U.K. |  | 841 |  |  | 390 |  |  | — |  |  | 1,231 |
Ireland |  | 46 |  |  | 45 |  |  | — |  |  | 91 |
Europe, Middle East, & Africa other than U.K. and Ireland |  | 1,415 |  |  | 481 |  |  | — |  |  | 1,896 |
Asia Pacific |  | 671 |  |  | 184 |  |  | — |  |  | 855 |
Total revenue |  | $ | 6,057 |  |  | $ | 2,836 |  |  | $ | (9) |  |  | $ | 8,884 |

|  | Six Months Ended June 30, 2024
|  | Risk Capital |  | Human Capital |  | Corporate/Eliminations |  | Total
U.S. |  | $ | 2,295 |  |  | $ | 1,077 |  |  | $ | (23) |  |  | $ | 3,349 |
Americas other than U.S. |  | 487 |  |  | 198 |  |  | — |  |  | 685 |
U.K. |  | 790 |  |  | 341 |  |  | — |  |  | 1,131 |
Ireland |  | 36 |  |  | 32 |  |  | — |  |  | 68 |
Europe, Middle East, & Africa other than U.K. and Ireland |  | 1,356 |  |  | 419 |  |  | — |  |  | 1,775 |
Asia Pacific |  | 661 |  |  | 161 |  |  | — |  |  | 822 |
Total revenue |  | $ | 5,625 |  |  | $ | 2,228 |  |  | $ | (23) |  |  | $ | 7,830 |

Contract Costs
An analysis of the changes in the net carrying amount of costs to fulfill contracts with customers are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Balance at beginning of period |  | $ | 302 |  |  | $ | 269 |  |  | $ | 424 |  |  | $ | 370 |
Additions |  | 409 |  |  | 386 |  |  | 827 |  |  | 766 |
Amortization |  | (448) |  |  | (390) |  |  | (992) |  |  | (868) |
Impairment |  | — |  |  | — |  |  | — |  |  | — |
Foreign currency translation and other |  | 10 |  |  | (1) |  |  | 14 |  |  | (4) |
Balance at end of period |  | $ | 273 |  |  | $ | 264 |  |  | $ | 273 |  |  | $ | 264 |

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An analysis of the changes in the net carrying amount of costs to obtain contracts with customers are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Balance at beginning of period |  | $ | 208 |  |  | $ | 194 |  |  | $ | 207 |  |  | $ | 195 |
Additions |  | 14 |  |  | 18 |  |  | 27 |  |  | 32 |
Amortization |  | (40) |  |  | (14) |  |  | (53) |  |  | (27) |
Impairment |  | — |  |  | — |  |  | — |  |  | — |
Foreign currency translation and other |  | 5 |  |  | (2) |  |  | 6 |  |  | (4) |
Balance at end of period |  | $ | 187 |  |  | $ | 196 |  |  | $ | 187 |  |  | $ | 196 |

4. Accelerating Aon United Program
In the third quarter of 2023, Aon initiated a three-year restructuring program called the Accelerating Aon United Program (the “Program” or the “AAU Program”) with the purpose of streamlining the Company’s technology infrastructure, optimizing its leadership structure and resource alignment, and reducing its real estate footprint to align to its hybrid working strategy. The Program includes technology-related costs to facilitate streamlining and simplifying operations, headcount reduction costs, and costs associated with asset impairments, including real estate consolidation and technology costs. The Program is an investment in the Company’s 3x3 Plan that brings together the best of the firm through its Aon United strategy, delivered as Risk Capital and Human Capital, and Aon’s Client Leadership model, powered by Aon Business Services.
Program charges are recognized within Accelerating Aon United Program expenses on the accompanying Condensed Consolidated Statements of Income and consist of the following cost activities:
•Technology and other – includes costs associated with actions taken to rationalize applications and to optimize technology across the Company. These costs may include termination fees and other non-capitalizable costs associated with Program initiatives, which include professional service fees.
•Workforce optimization – includes costs associated with headcount reduction and other separation-related costs.
•Asset impairments – includes non-cash costs associated with impairment of assets, as they are identified, including ROU lease assets, leasehold improvements, and other capitalized assets no longer providing economic benefit.
The Program is currently expected to result in cumulative costs of $1.0 billion, consisting of approximately $0.9 billion of cash charges and approximately $0.1 billion of non-cash charges. For the three and six months ended June 30, 2025, total Program costs incurred were $94 million and $204 million, respectively. Over the life of the Program, the Risk Capital segment is expected to incur approximately $220 million of charges, while the Human Capital segment is expected to incur approximately $60 million of charges, with the remaining charges relating to corporate expenses.
Total Program costs incurred for the three and six months ended June 30, 2025 and 2024 are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Risk Capital |  | $ | 32 |  |  | $ | 49 |  |  | $ | 51 |  |  | $ | 92 |
Human Capital |  | 6 |  |  | 12 |  |  | 10 |  |  | 23 |
Corporate |  | 56 |  |  | 71 |  |  | 143 |  |  | 136 |
Total |  | $ | 94 |  |  | $ | 132 |  |  | $ | 204 |  |  | $ | 251 |

The Company’s unpaid liabilities for charges under the Program are primarily included in Accounts payable and accrued liabilities and Other non-current liabilities in the Condensed Consolidated Statements of Financial Position.
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The changes in the Company’s liabilities for the Program as of June 30, 2025 are as follows (in millions):

| Technology and other |  | Workforce optimization |  | Asset impairments |  | Total
Liability balance as of December 31, 2024 | $ | 17 |  |  | $ | 97 |  |  | $ | — |  |  | $ | 114 |
Charges | 100 |  |  | 100 |  |  | 4 |  |  | 204 |
Cash payments | (84) |  |  | (82) |  |  | — |  |  | (166) |
Foreign currency translation and other | — |  |  | 5 |  |  | — |  |  | 5 |
Non-cash charges | (2) |  |  | (17) |  |  | (4) |  |  | (23) |
Liability balance as of June 30, 2025 | $ | 31 |  |  | $ | 103 |  |  | $ | — |  |  | $ | 134 |
Total costs incurred from inception to date | $ | 240 |  |  | $ | 400 |  |  | $ | 88 |  |  | $ | 728 |

5. Cash and Cash Equivalents and Short-Term Investments
Cash and cash equivalents include cash balances and all highly liquid instruments with initial maturities of three months or less. Short-term investments consist of money market funds. The estimated fair value of Cash and cash equivalents and Short-term investments approximates their carrying values.
At June 30, 2025, Cash and cash equivalents and Short-term investments were $1.4 billion compared to $1.3 billion at December 31, 2024. Of the total balances, $158 million and $123 million were restricted as to their use at June 30, 2025 and December 31, 2024, respectively. Included within Short-term investments as of June 30, 2025 and December 31, 2024, were £66 million ($90 million at June 30, 2025 exchange rates) and £63 million ($79 million at December 31, 2024 exchange rates), respectively, of operating funds required to be held by the Company in the U.K. by the FCA, a U.K.-based regulator.
6. Other Financial Data
Condensed Consolidated Statements of Income Information
Other Income (Expense)
Other income (expense) consists of the following (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Extinguishment of debt |  | $ | — |  |  | $ | (6) |  |  | $ | — |  |  | $ | (6) |
Gain from sales of businesses |  | — |  |  | 257 |  |  | — |  |  | 257 |
Equity earnings |  | 3 |  |  | 1 |  |  | 1 |  |  | 3 |
Pension and other postretirement |  | (21) |  |  | (11) |  |  | (44) |  |  | (21) |
Foreign currency remeasurement |  | (38) |  |  | 5 |  |  | (54) |  |  | 9 |
Financial instruments and other (1) |  | 112 |  |  | (10) |  |  | 143 |  |  | 69 |
Total |  | $ | 56 |  |  | $ | 236 |  |  | $ | 46 |  |  | $ | 311 |

(1)During the three and six months ended June 30, 2025, an $88 million and $108 million gain was recognized, respectively, compared to $82 million recognized for the six months ended June 30, 2024, which was all recognized in the first quarter of 2024. These gains are related to deferred consideration from the affiliates of The Blackstone Group L.P. and the other designated purchasers related to a divestiture completed in a prior year period. Refer to Note 7 “Acquisitions and Dispositions of Businesses” for additional information.
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Condensed Consolidated Statements of Financial Position Information
Allowance for Doubtful Accounts
Changes in the net carrying amount of allowance for doubtful accounts are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Balance at beginning of period |  | $ | 74 |  |  | $ | 81 |  |  | $ | 75 |  |  | $ | 79 |
Provision |  | 3 |  |  | 6 |  |  | 6 |  |  | 11 |
Accounts written off, net of recoveries |  | (1) |  |  | — |  |  | (6) |  |  | (2) |
Foreign currency translation and other |  | 3 |  |  | — |  |  | 4 |  |  | (1) |
Balance at end of period |  | $ | 79 |  |  | $ | 87 |  |  | $ | 79 |  |  | $ | 87 |

Other Current Assets
The components of Other current assets are as follows (in millions):

As of | June 30, 2025 |  | December 31, 2024
Costs to fulfill contracts with customers (1) | $ | 273 |  |  | $ | 424 |
Prepaid expenses | 170 |  |  | 135 |
Taxes receivable | 89 |  |  | 43 |
Other (2) | 322 |  |  | 157 |
Total | $ | 854 |  |  | $ | 759 |

(1)Refer to Note 3 “Revenue from Contracts with Customers” for further information.
(2)Includes $1 million as of December 31, 2024 that was previously classified as “Assets held for sale” within Aon’s Annual Report on Form 10-K filed February 18, 2025. The prior year balance has been reclassified to conform to current year presentation.
Other Non-Current Assets
The components of Other non-current assets are as follows (in millions):

As of | June 30, 2025 |  | December 31, 2024
Costs to obtain contracts with customers (1) | $ | 187 |  |  | $ | 207 |
Investments | 101 |  |  | 90 |
Taxes receivable | 84 |  |  | 90 |
Other (2) (3) | 200 |  |  | 611 |
Total | $ | 572 |  |  | $ | 998 |

(1)Refer to Note 3 “Revenue from Contracts with Customers” for further information.
(2)Includes $9 million as of December 31, 2024 that was previously classified as “Leases” within Aon’s Annual Report on Form 10-K filed February 18, 2025. The prior year balance has been reclassified to conform to current year presentation.
(3)Includes $416 million as of December 31, 2024 of consideration paid into an escrow account related to the acquisition of Griffiths & Armour, which closed on January 1, 2025. Refer to Note 7 “Acquisitions and Dispositions of Businesses” for additional information.
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Other Current Liabilities
The components of Other current liabilities are as follows (in millions):

As of | June 30, 2025 |  | December 31, 2024
Deferred revenue (1) | $ | 385 |  |  | $ | 280 |
Leases | 185 |  |  | 191 |
Taxes payable | 166 |  |  | 260 |
Contingent consideration | 58 |  |  | 93 |
Other | 1,473 |  |  | 949 |
Total | $ | 2,267 |  |  | $ | 1,773 |

(1)During the three and six months ended June 30, 2025, revenue of $236 million and $466 million, respectively, was recognized in the Condensed Consolidated Statements of Income that was previously deferred. During the three and six months ended June 30, 2024, revenue of $199 million and $378 million, respectively, was recognized in the Condensed Consolidated Statements of Income that was previously deferred.
Other Non-Current Liabilities
The components of Other non-current liabilities are as follows (in millions):

As of | June 30, 2025 |  | December 31, 2024
Taxes payable | $ | 961 |  |  | $ | 885 |
Contingent consideration | 113 |  |  | 104 |
Compensation and benefits | 55 |  |  | 61 |
Deferred revenue | 34 |  |  | 30 |
Other | 86 |  |  | 64 |
Total | $ | 1,249 |  |  | $ | 1,144 |

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7. Acquisitions and Dispositions of Businesses
Completed Acquisitions
On January 1, 2025, the Company completed the acquisition of 100% of the partnership interests and share capital of Griffiths & Armour, an insurance broker in the United Kingdom.
In total, the Company completed two and nine acquisitions during the three and six months ended June 30, 2025, respectively. The Company completed one acquisition within Risk Capital and one within Human Capital during the three months ended June 30, 2025, and seven within Risk Capital and two within Human Capital, during the six months ended June 30, 2025. The Company completed eight acquisitions, five within Risk Capital and three within Human Capital, during the three and six months ended June 30, 2024. Acquisitions that impact multiple segments are categorized by the segment primarily impacted. The following table includes the preliminary fair values of consideration transferred, assets acquired, and liabilities assumed as a result of the Company’s acquisitions (in millions):

|  | Six Months Ended June 30, 2025
Consideration transferred: |  |
Cash (1) |  | $ | 631 |
Deferred and contingent consideration |  | 38 |
Aggregate consideration transferred |  | $ | 669 |
Assets acquired: |  |
Goodwill |  | 362 |
Intangible assets |  | 322 |
Other assets (2) |  | 126 |
Total assets acquired |  | 810 |
Liabilities assumed: |  |
Total liabilities assumed |  | 141 |
Net assets acquired |  | $ | 669 |

(1)Includes $416 million as of December 31, 2024 of consideration paid into an escrow account related to the acquisition of Griffiths & Armour, which closed on January 1, 2025.
(2)Includes Cash and cash equivalents of $33 million and $42 million in funds held on behalf of clients.
The results of operations of these acquisitions are included in the Condensed Consolidated Financial Statements as of the respective acquisition dates. The Company’s results of operations would not have been materially different if these acquisitions had been reported from the beginning of the period in which they were acquired.
Significant Prior Year Acquisitions
On April 25, 2024, the Company acquired 100% of the outstanding equity interests of NFP Intermediate Holdings A Corp. (the “NFP Transaction”) in a cash-and-stock merger for an aggregate U.S. GAAP purchase price totaling $9.1 billion, including approximately $3.2 billion used to settle indebtedness of NFP and cash consideration to the selling shareholders, and approximately 19 million class A ordinary shares with a fair value of approximately $5.9 billion, based on the Company’s closing stock price on April 25, 2024. In addition, the Company had other adjustments of $3.9 billion for cash and certain assumed liabilities. As part of the NFP Transaction, the Company acquired certain less-than-wholly owned entities, resulting in the recognition of noncontrolling interests, which are described further below.
The Company financed the NFP Transaction, in part, with the net proceeds from Senior Notes issued on March 1, 2024 totaling to an aggregate amount of $6.0 billion and proceeds from a $2.0 billion delayed draw term loan which was drawn on April 25, 2024. Refer to Note 9 “Debt” for further information.
Aon accounted for its business combinations under the acquisition method of accounting. The acquisition method requires the Company to measure identifiable assets acquired and liabilities assumed at their fair values as of the acquisition date, with the excess of the consideration transferred over those fair values recorded as goodwill. Determining the fair value of intangible assets acquired requires significant judgements, assumptions, and estimates about future events, which the Company believes are reasonable. Use of different estimates and judgements could produce materially different results. These estimates are refined over a measurement period, not to exceed one year from the acquisition date.
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The fair values of consideration transferred, assets acquired, liabilities assumed, and redeemable and nonredeemable noncontrolling interests are shown below, where purchase accounting and subsequent measurement period adjustments were finalized in the second quarter of 2025. The following table includes these amounts recognized as of June 30, 2025 as a result of the Company’s acquisition of NFP (in millions):

|  | NFP Acquisition |  |
Consideration transferred: |  |  |  |
Cash |  | $ | 3,247 |  |  |
Class A ordinary shares issued |  | 5,882 |  |  |
Aggregate consideration transferred |  | $ | 9,129 |  |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | $ | 294 |  |  |
Receivables |  | 329 |  |  |
Fiduciary assets (1) |  | 411 |  |  |
Goodwill |  | 6,838 |  |  |
Other intangible assets: |  |  |  |
Customer-related and contract-based |  | 5,950 |  |  |
Tradenames |  | 800 |  |  |
Technology and other |  | 25 |  |  |
Operating lease right-of-use assets |  | 138 |  |  |
Current assets |  | 82 |  |  |
Non-current assets |  | 108 |  |  |
Total assets acquired |  | 14,975 |  |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | $ | 283 |  |  |
Fiduciary liabilities |  | 411 |  |  |
Current liabilities |  | 241 |  |  |
Long-term debt |  | 3,422 |  |  |
Non-current operating lease liabilities |  | 125 |  |  |
Deferred tax liabilities (2) |  | 1,013 |  |  |
Non-current liabilities |  | 158 |  |  |
Total liabilities assumed |  | 5,653 |  |  |
Less: Fair value of redeemable noncontrolling interests (3) |  | (108) |  |  |
Less: Fair value of nonredeemable noncontrolling interests |  | (85) |  |  |
Net assets acquired |  | $ | 9,129 |  |  |

(1)Includes $277 million of funds held on behalf of clients.
(2)As of June 30, 2025, the NFP deferred tax liability related to the U.S. has been netted with the Aon deferred tax asset related to the U.S. and presented as a net deferred tax asset on the Consolidated Statements of Financial Position.
(3)The fair value of the noncontrolling interests acquired was estimated using a DCF model under the income approach and used estimated financial projections developed by management applying market participant assumptions.
Since the acquisition date, the Company made measurement period adjustments related to the NFP Transaction which primarily included the following:
•An increase in the fair value of customer-related and contract-based intangible assets of $125 million;
•A decrease in the fair value of acquired notes receivable of $107 million (recorded within other current assets and other non-current assets); and
•A $110 million decrease in deferred tax liabilities primarily as a result of adjustments to state deferred taxes and deferred taxes recorded on other measurement period adjustments;
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Collectively, these adjustments, along with other insignificant adjustments not described above, resulted in a $115 million decrease to goodwill. The measurement period adjustments had an insignificant impact on Net income for the six months ended June 30, 2025.
The purchase price related to the NFP Transaction exceeded the estimated fair value of the tangible and identifiable intangible assets acquired and liabilities assumed and, as a result of the purchase allocation, the Company recorded goodwill of approximately $6.8 billion, which is not deductible for tax purposes. The goodwill recognized is attributable primarily to anticipated growth opportunities and synergies as a result of the NFP Transaction which provides the Company with an expanded presence in the large and fast-growing middle-market. As of June 30, 2025, the company had allocated $2.6 billion of the acquired goodwill to Risk Capital and $4.2 billion of the acquired goodwill to Human Capital.
The fair value of the assets acquired and liabilities assumed in the NFP Transaction approximated their carrying values as of the acquisition date with the exception of customer-related and contract-based assets, tradename, technology, and contingent consideration obligations. Intangible assets acquired had a weighted average useful economic life of 19 years.
Supplemental Pro Forma Combined Information (Unaudited)
The following unaudited pro forma combined financial information presents the combined results of operations of the Company as if the NFP Transaction occurred on January 1, 2023. The unaudited pro forma financial information is presented for informational purposes only and is not indicative of the results of operations that would have been achieved if the NFP Transaction had taken place on the date indicated or of results that may occur in the future (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2024 | 2023 |  | 2024 | 2023
Revenue |  | $ | 3,910 |  | $ | 3,729 |  |  | $ | 8,528 |  | $ | 8,099 |
Net income attributable to Aon shareholders |  | 465 |  | 427 |  |  | 1,401 |  | 1,269 |

The unaudited pro forma financial information is based on historical information of the Company and NFP, along with certain material pro forma adjustments. The material pro forma adjustments primarily consist of (i) incremental amortization expense based on the preliminary fair values of the intangible assets acquired; (ii) interest expense to reflect Aon’s borrowings under the Senior Notes offering and delayed draw term loan; (iii) increased compensation expense relating to the issuance of certain cash and equity plans related to the NFP Transaction; (iv) nonrecurring transaction costs; (v) accounting policy alignment adjustments, and (vi) income tax impact of the aforementioned pro forma adjustments. In addition, the Company reflected pro forma adjustments related to measurement period adjustments.
Completed Dispositions
The Company completed one disposition within Human Capital in the three and six months ended June 30, 2025. The Company completed two dispositions, both within Risk Capital, during the three months ended June 30, 2024 and three dispositions, two within Risk Capital and one within Human Capital, during the six months ended June 30, 2024. Dispositions that impact multiple segments are categorized by the segment primarily impacted.
There were insignificant pretax gains recognized related to dispositions for the three and six months ended June 30, 2025. There were $257 million pretax gains recognized related to dispositions for the three and six months ended June 30, 2024. Gains recognized as a result of a disposition are included in Other income (expense) in the Condensed Consolidated Statements of Income.
Other Significant Activity
On May 1, 2017, the Company completed the sale of its benefits administration and business process outsourcing business (the “Divested Business”) to an entity controlled by affiliates of The Blackstone Group L.P. (the “Buyer”) and certain designated purchasers that are direct or indirect subsidiaries of the Buyer. The Buyer purchased all of the outstanding equity interests of the Divested Business, plus certain related assets and liabilities for a purchase price of $4.3 billion in cash paid at closing and deferred consideration of up to $500 million. During the three and six months ended June 30, 2025, the Company earned $88 million and $108 million, respectively, of deferred consideration from the Buyer and the other designated purchasers, compared to $82 million earned during the six months ended June 30, 2024, which was all earned in the first quarter of 2024. These gains are recorded in Other income (expense) in the Condensed Consolidated Statements of Income. In total, the Company has earned $192 million in deferred consideration related to this transaction as of June 30, 2025.
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8. Goodwill and Other Intangible Assets
The changes in the net carrying amount of goodwill for the six months ended June 30, 2025 are as follows (in millions):

| Risk Capital | Human Capital | Total
Balance as of December 31, 2024 | $ | 8,785 |  | $ | 6,449 |  | $ | 15,234 |
Goodwill related to current year acquisitions | 346 |  | 16 |  | 362 |
Measurement period adjustments related to prior year acquisitions | (11) |  | (17) |  | (28) |
Foreign currency translation and other | 301 |  | 155 |  | 456 |
Balance as of June 30, 2025 | $ | 9,421 |  | $ | 6,603 |  | $ | 16,024 |

Other intangible assets by asset class are as follows (in millions):

| June 30, 2025 |  | December 31, 2024
| Gross Carrying Amount |  | Accumulated Amortization and Impairment |  | Net Carrying Amount |  | Gross Carrying Amount |  | Accumulated Amortization and Impairment |  | Net Carrying Amount
Customer-related and contract-based | $ | 8,417 |  |  | $ | 2,448 |  |  | $ | 5,969 |  |  | $ | 7,994 |  |  | $ | 2,050 |  |  | $ | 5,944 |
Tradenames | 811 |  |  | 96 |  |  | 715 |  |  | 812 |  |  | 66 |  |  | 746 |
Technology and other | 369 |  |  | 320 |  |  | 49 |  |  | 366 |  |  | 313 |  |  | 53 |
Total | $ | 9,597 |  |  | $ | 2,864 |  |  | $ | 6,733 |  |  | $ | 9,172 |  |  | $ | 2,429 |  |  | $ | 6,743 |

The estimated future amortization for finite-lived intangible assets as of June 30, 2025 is as follows (in millions):

Remainder of 2025 | $ | 403 |
2026 | 739 |
2027 | 680 |
2028 | 625 |
2029 | 576 |
2030 | 528 |
Thereafter | 3,182 |
Total | $ | 6,733 |

9. Debt
Notes
In May 2025, Aon Global Limited’s €500 million ($585 million at June 30, 2025 exchange rates) 2.875% Senior Notes due May 2026 were classified as Short-term debt and current portion of long-term debt in the Consolidated Statement of Financial Position as the date of maturity is in less than one year. The Company expects to use cash flow from operations and available cash on hand to repay these Senior Notes.
In December 2024, Aon Global Limited’s $750 million 3.875% Senior Notes due December 2025 were classified as Short-term debt and current portion of long-term debt in the Consolidated Statement of Financial Position as the date of maturity is in less than one year. The Company expects to use cash flow from operations and available cash on hand to repay these Senior Notes.
In June 2024, Aon Global Limited’s $600 million 3.50% Senior Notes matured and were repaid in full.
On April 25, 2024, Aon North America, Inc. drew its $2 billion delayed draw term loan and used proceeds, together with the proceeds of the Senior Notes issued on March 1, 2024 described below, to pay a portion of cash consideration in connection with the acquisition of NFP, completed on April 25, 2024, (the “NFP Transaction”), to repay certain debt of NFP, and to pay related fees and expenses. The term loan matures on April 24, 2027 and is prepayable at any time. In the second quarter of 2025, Aon North America, Inc. repaid $300 million of the outstanding balance under the term loan facility, and as of June 30, 2025, has repaid $1.2 billion of the outstanding balance. The remaining outstanding balance is $800 million.
On April 2, 2024, Aon plc announced that its wholly owned subsidiary, Randolph Acquisition Corp., commenced cash tender offers for any and all of the outstanding 6.875% Senior Notes due 2028, 4.875% Senior Secured Notes due 2028, 7.500%
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Senior Secured Notes due 2030 and 8.500% Senior Secured Notes due 2031, each issued by NFP Corp. (together, the “NFP Notes”), upon the terms and subject to the conditions set forth in the Offer to Purchase and Consent Solicitation Statement, dated as of April 2, 2024. The total amount tendered pursuant to the tender offers was approximately $3.3 billion, excluding premiums. On April 26, 2024, Randolph Acquisition Corp. purchased those NFP Notes that were validly tendered and not validly withdrawn prior to April 15, 2024, effecting the early settlement of the offers (the “Early Settlement”). In addition, on April 16, 2024, NFP Corp. delivered notices of redemption of all NFP Notes not validly tendered pursuant to the offers and purchased at the Early Settlement, at a purchase price equal to the price paid to holders of the NFP Notes in connection with the Early Settlement, with a redemption date of April 26, 2024. As a result of the Early Settlement of the offers and the related redemption which occurred on April 26, 2024, no NFP Notes remain outstanding. Aon plc incurred $6 million of debt extinguishment charges in the second quarter of 2024 related to costs related to the NFP Transaction.
On March 1, 2024, Aon North America, Inc. issued $600 million 5.125% Senior Notes due in March 2027, $1 billion 5.150% Senior Notes due in March 2029, $650 million 5.300% Senior Notes due in March 2031, $1.75 billion 5.450% Senior Notes due in March 2034, and $2 billion 5.750% Senior Notes due in March 2054, totaling to an aggregate amount of $6 billion. The Company intends to use the net proceeds from the offering for general corporate purposes, including a portion of which was used to pay a portion of the cash consideration in connection with the NFP Transaction, to repay certain debt of NFP, and to pay related fees and expenses.
Revolving Credit Facilities
As of June 30, 2025, Aon plc had two primary committed credit facilities outstanding: its $1.0 billion multi-currency U.S. credit facility expiring in September 2027 and its $1.0 billion multi-currency U.S. credit facility expiring in October 2028. In aggregate, these two facilities provide $2.0 billion in available credit.
Each of these primary committed credit facilities includes customary representations, warranties, and covenants, including financial covenants that require Aon to maintain specified ratios of adjusted consolidated EBITDA to consolidated interest expense and consolidated debt to adjusted consolidated EBITDA, in each case, tested quarterly. Aon did not have borrowings under either of these primary committed credit facilities as of June 30, 2025 or December 31, 2024. Additionally, Aon was in compliance with the financial covenants and all other covenants contained therein during the rolling 12 months ended June 30, 2025 and December 31, 2024.
Commercial Paper
Aon Corporation has established a U.S. commercial paper program (the “U.S. Program”) and Aon Global Holdings plc has established a European multi-currency commercial paper program (the “European Program” and, together with the U.S. Program, the “Commercial Paper Programs”). Commercial paper may be issued in aggregate principal amounts of up to approximately $1.3 billion under the U.S. Program and €625 million ($731 million at June 30, 2025 exchange rates) under the European Program, not to exceed the amount of the Company’s committed credit facilities, which was $2.0 billion at June 30, 2025. The aggregate capacity of the Commercial Paper Program remains fully backed by the Company’s committed credit facilities. The U.S. Program was fully and unconditionally guaranteed by Aon plc, Aon Global Limited, Aon North America, Inc., and Aon Global Holdings plc and the European Program was fully and unconditionally guaranteed by Aon plc, Aon Global Limited, Aon North America, Inc., and Aon Corporation.
Commercial paper outstanding, which is included in Short-term debt and current portion of long-term debt in the Company’s Condensed Consolidated Statements of Financial Position, is as follows (in millions):

| June 30, 2025 | December 31, 2024
Commercial paper outstanding | $ | 501 |  | $ | — |

The weighted average commercial paper outstanding and its related interest rates are as follows (in millions, except percentages):

|  | Three Months Ended June 30, | Six Months Ended June 30,
|  | 2025 |  | 2024 | 2025 |  | 2024
Weighted average commercial paper outstanding |  | $ | 856 |  |  | $ | 34 |  | $ | 528 |  |  | $ | 207 |
Weighted average interest rate of commercial paper outstanding |  | 4.24 | % |  | 5.50 | % | 4.30 | % |  | 5.63 | %

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10. Income Taxes
The effective tax rate on Net income was 15.5% and 19.3% for the three and six months ended June 30, 2025, respectively. The effective tax rate on Net income was 22.9% and 23.1% for the three and six months ended June 30, 2024, respectively.
For the three and six months ended June 30, 2025, the tax rate was primarily driven by the geographical distribution of income and certain discrete items, including the tax benefit associated with the anticipated sale of certain assets and liabilities classified as held for sale and share-based payments partially offset by the unfavorable impact of other discrete items.
For the three and six months ended June 30, 2024, the tax rate was primarily driven by the geographical distribution of income and certain discrete items, including the favorable impacts of share-based payments offset by the unfavorable impact of discrete items.
11. Shareholders’ Equity
Ordinary Shares
Aon has a share repurchase program authorized by the Company’s Board of Directors (“the Repurchase Program”). The Repurchase Program was established in April 2012 with $5.0 billion in authorized repurchases, and was increased by $5.0 billion in authorized repurchases in each of November 2014, June 2017, and November 2020, and by $7.5 billion in February 2022 for a total of $27.5 billion in repurchase authorizations.
Under the Repurchase Program, the Company’s class A ordinary shares may be repurchased through the open market or in privately negotiated transactions, from time to time, based on prevailing market conditions, and will be funded from available capital.
The following table summarizes the Company’s share repurchase activity (in millions, except per share data):

| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Shares repurchased | 0.7 |  |  | 0.8 |  |  | 1.3 |  |  | 1.6 |
Average price per share | $ | 361.25 |  |  | $ | 298.09 |  |  | $ | 376.76 |  |  | $ | 304.20 |
Repurchase costs recorded to accumulated deficit | $ | 250 |  |  | $ | 250 |  |  | $ | 500 |  |  | $ | 500 |

At June 30, 2025, the remaining authorized amount for share repurchases under the Repurchase Program was approximately $1.8 billion. Under the Repurchase Program, the Company has repurchased a total of 173.5 million shares for an aggregate cost of approximately $25.7 billion.
Weighted Average Ordinary Shares
Weighted average ordinary shares outstanding are as follows (in millions):

| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Basic weighted average ordinary shares outstanding | 216.2 |  |  | 212.5 |  |  | 216.3 |  |  | 205.8 |
Dilutive effect of potentially issuable shares | 1.1 |  |  | 0.8 |  |  | 1.3 |  |  | 0.9 |
Diluted weighted average ordinary shares outstanding | 217.3 |  |  | 213.3 |  |  | 217.6 |  |  | 206.7 |

Potentially issuable shares are not included in the computation of Diluted net income per share attributable to Aon shareholders if their inclusion would be antidilutive. There were 0.4 million and 0.1 million shares excluded from the calculation for the three and six months ended June 30, 2025, respectively. There were 1.4 million and 0.6 million shares excluded from the calculation for the three and six months ended June 30, 2024, respectively.
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Accumulated Other Comprehensive Loss
Changes in Accumulated other comprehensive loss by component, net of related tax, are as follows (in millions):

| Change in Fair Value of Financial Instruments (1) |  | Foreign Currency Translation Adjustments |  | Postretirement Benefit Obligation (2) |  | Total
Balance at January 1, 2025 | $ | 74 |  |  | $ | (2,051) |  |  | $ | (2,768) |  |  | $ | (4,745) |
Other comprehensive income (loss) before reclassifications, net | 17 |  |  | 843 |  |  | (7) |  |  | 853 |
Amounts reclassified from accumulated other comprehensive income |  |  |  |  |  |  |
Amounts reclassified from accumulated other comprehensive income (loss) | (6) |  |  | — |  |  | 72 |  |  | 66 |
Tax expense | 2 |  |  | — |  |  | (19) |  |  | (17) |
Amounts reclassified from accumulated other comprehensive income (loss), net | (4) |  |  | — |  |  | 53 |  |  | 49 |
Net current period other comprehensive income (loss) | 13 |  |  | 843 |  |  | 46 |  |  | 902 |
Balance at June 30, 2025 | $ | 87 |  |  | $ | (1,208) |  |  | $ | (2,722) |  |  | $ | (3,843) |

| Change in Fair Value of Financial Instruments (1) |  | Foreign Currency Translation Adjustments |  | Postretirement Benefit Obligation (2) |  | Total
Balance at January 1, 2024 | $ | 2 |  |  | $ | (1,584) |  |  | $ | (2,791) |  |  | $ | (4,373) |
Other comprehensive income (loss) before reclassifications, net | 75 |  |  | (220) |  |  | (13) |  |  | (158) |
Amounts reclassified from accumulated other comprehensive income |  |  |  |  |  |  |
Amounts reclassified from accumulated other comprehensive income | 2 |  |  | — |  |  | 70 |  |  | 72 |
Tax expense | (1) |  |  | — |  |  | (18) |  |  | (19) |
Amounts reclassified from accumulated other comprehensive income, net | 1 |  |  | — |  |  | 52 |  |  | 53 |
Net current period other comprehensive income (loss) | 76 |  |  | (220) |  |  | 39 |  |  | (105) |
Balance at June 30, 2024 | $ | 78 |  |  | $ | (1,804) |  |  | $ | (2,752) |  |  | $ | (4,478) |

(1)Reclassifications from this category included in Accumulated other comprehensive loss are recorded in Total revenue, Interest expense, and Compensation and benefits in the Condensed Consolidated Statements of Income. Refer to Note 13 “Derivatives and Hedging” for further information regarding the Company’s derivative and hedging activity.
(2)Reclassifications from this category included in Accumulated other comprehensive loss are recorded in Other income (expense) in the Condensed Consolidated Statements of Income.
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12. Employee Benefits
The following table provides the components of the net periodic (benefit) cost recognized in the Condensed Consolidated Statements of Income for Aon’s significant U.K., U.S., and other major pension plans, which are located in the Netherlands and Canada. Service cost is reported in Compensation and benefits and all other components are reported in Other income (expense) as follows (in millions):

| Three Months Ended June 30,
| U.K. |  | U.S. |  | Other
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Service cost | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Interest cost | 39 |  |  | 36 |  |  | 25 |  |  | 23 |  |  | 10 |  |  | 10 |
Expected return on plan assets, net of administration expenses | (45) |  |  | (47) |  |  | (30) |  |  | (35) |  |  | (14) |  |  | (14) |
Amortization of prior-service cost | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of net actuarial loss | 22 |  |  | 21 |  |  | 9 |  |  | 8 |  |  | 4 |  |  | 3 |
Net periodic cost (benefit) | $ | 16 |  |  | $ | 10 |  |  | $ | 4 |  |  | $ | (4) |  |  | $ | — |  |  | $ | (1) |
| Six Months Ended June 30,
| U.K. |  | U.S. |  | Other
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Service cost | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Interest cost | 76 |  |  | 71 |  |  | 51 |  |  | 46 |  |  | 19 |  |  | 19 |
Expected return on plan assets, net of administration expenses | (88) |  |  | (94) |  |  | (60) |  |  | (68) |  |  | (26) |  |  | (27) |
Amortization of prior-service cost | 1 |  |  | 1 |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of net actuarial loss | 44 |  |  | 41 |  |  | 18 |  |  | 15 |  |  | 7 |  |  | 6 |
Net periodic (benefit) cost | $ | 33 |  |  | $ | 19 |  |  | $ | 9 |  |  | $ | (7) |  |  | $ | — |  |  | $ | (2) |

Contributions
Assuming no additional contributions are agreed to with, or required by, the pension plan trustees, the Company expects to make total cash contributions of approximately $2 million, $76 million, and $10 million (at December 31, 2024 exchange rates) to its significant U.K., U.S., and other major pension plans, respectively, during 2025. The following table summarizes contributions made to the Company’s significant pension plans (in millions):

| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Contributions to U.K. pension plans | $ | 1 |  |  | $ | 1 |  |  | $ | 2 |  |  | $ | 2 |
Contributions to U.S. pension plans | 17 |  |  | 4 |  |  | 44 |  |  | 18 |
Contributions to other major pension plans | 6 |  |  | 5 |  |  | 8 |  |  | 7 |
Total contributions | $ | 24 |  |  | $ | 10 |  |  | $ | 54 |  |  | $ | 27 |

13. Derivatives and Hedging
The Company is exposed to market risks, including changes in foreign currency exchange rates and interest rates. To manage the risk related to these exposures, the Company enters into various derivative instruments that reduce these risks by creating offsetting exposures. The Company does not enter into derivative transactions for trading or speculative purposes.
Foreign Exchange Risk Management
The Company is exposed to foreign exchange risk when it earns revenues, pays expenses, enters into monetary intercompany transfers or other transactions denominated in a currency that differs from its functional currency. The Company uses foreign exchange derivatives, typically forward contracts, options and cross currency swaps, to reduce its overall exposure to the effects of currency fluctuations on cash flows. These exposures are hedged, on average, for less than two years. These derivatives are
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accounted for as hedges, and changes in fair value are recorded each period in Other comprehensive income (loss) in the Condensed Consolidated Statements of Comprehensive Income.
The Company also uses foreign exchange derivatives, typically forward contracts and options, to economically hedge the currency exposure of the Company’s global liquidity profile, including monetary assets or liabilities that are denominated in a non-functional currency of an entity, typically on a rolling 90-day basis, but may be for up to one year in the future. These derivatives are not accounted for as hedges, and changes in fair value are recorded each period in Other income (expense) in the Condensed Consolidated Statements of Income.
The notional and fair values of derivative instruments are as follows (in millions):

| Notional Amount |  | Net Amount of Derivative Assets Presented in the Statements of Financial Position (1) |  | Net Amount of Derivative Liabilities Presented in the Statements of Financial Position (2)
| June 30, 2025 |  | December 31, 2024 |  | June 30, 2025 |  | December 31, 2024 |  | June 30, 2025 |  | December 31, 2024
Foreign exchange contracts |  |  |  |  |  |  |  |  |  |  |
Accounted for as hedges | $ | 480 |  |  | $ | 597 |  |  | $ | 30 |  |  | $ | 25 |  |  | $ | — |  |  | $ | — |
Not accounted for as hedges (3) | 580 |  |  | 394 |  |  | 1 |  |  | — |  |  | — |  |  | 1 |
Total | $ | 1,060 |  |  | $ | 991 |  |  | $ | 31 |  |  | $ | 25 |  |  | $ | — |  |  | $ | 1 |

(1)Included within Other current assets ($26 million at June 30, 2025 and $15 million at December 31, 2024) or Other non-current assets ($5 million at June 30, 2025 and $10 million at December 31, 2024).
(2)Included within Other current liabilities ($1 million at December 31, 2024).
(3)These contracts typically are for 90-day durations and executed close to the last day of the most recent reporting month, thereby resulting in nominal fair values at the balance sheet date.
The amounts of derivative gains recognized in the Condensed Consolidated Financial Statements are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Gain recognized in Accumulated other comprehensive loss |  | $ | 20 |  |  | $ | 4 |  |  | $ | 22 |  |  | $ | 101 |

The amounts of derivative gains (losses) reclassified from Accumulated other comprehensive loss to the Condensed Consolidated Statements of Income are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Total revenue |  | $ | 7 |  |  | $ | 2 |  |  | $ | 5 |  |  | $ | (2) |
Interest expense |  | $ | 1 |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |
Total |  | $ | 8 |  |  | $ | 2 |  |  | $ | 6 |  |  | $ | (2) |

The Company estimates that approximately $15 million of pretax gains currently included within Accumulated other comprehensive loss will be reclassified into earnings in the next twelve months.
During the three and six months ended June 30, 2025, the Company recorded a gain of $24 million and $37 million, respectively, in Other income (expense) for foreign exchange derivatives not designated or qualifying as hedges. During the three and six months ended June 30, 2024, the Company recorded losses of $6 million and $9 million, respectively, in Other income (expense) for foreign exchange derivatives not designated or qualifying as hedges.
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14. Fair Value Measurements and Financial Instruments
Accounting standards establish a three-tier fair value hierarchy that prioritizes the inputs used in measuring fair values as follows:
•Level 1 — observable inputs such as quoted prices for identical assets in active markets;
•Level 2 — inputs other than quoted prices for identical assets in active markets, that are observable either directly or indirectly; and
•Level 3 — unobservable inputs in which there is little or no market data which requires the use of valuation techniques and the development of assumptions.
The following methods and assumptions are used to estimate the fair values of the Company’s financial instruments:
Money market funds consist of institutional prime, treasury, and government money market funds. The Company reviews treasury and government money market funds to obtain reasonable assurance that the fund net asset value is $1 per share, and reviews the floating net asset value of institutional prime money market funds for reasonableness.
Equity investments consist of equity securities and equity derivatives valued using the closing stock price on a national securities exchange. Over-the-counter equity derivatives are valued using observable inputs such as underlying prices of the underlying security and volatility. On a sample basis, the Company reviews the listing of Level 1 equity securities in the portfolio, agrees the closing stock prices to a national securities exchange, and independently verifies the observable inputs for Level 2 equity derivatives and securities.
Fixed income investments consist of certain categories of bonds and derivatives. Corporate, government, and agency bonds are valued by pricing vendors who estimate fair value using recently executed transactions and proprietary models based on observable inputs, such as interest rate spreads, yield curves, and credit risk. Asset-backed securities are valued by pricing vendors who estimate fair value using DCF models utilizing observable inputs based on trade and quote activity of securities with similar features. Fixed income derivatives are valued by pricing vendors using observable inputs such as interest rates and yield curves. The Company obtains an understanding of the models, inputs, and assumptions used in developing prices provided by its vendors through discussions with the fund managers. The Company independently verifies the observable inputs, as well as assesses assumptions used for reasonableness based on relevant market conditions and internal Company guidelines. If an assumption is deemed unreasonable, based on internal Company guidelines, it is then reviewed by management and the fair value estimate provided by the vendor is adjusted, if deemed appropriate. These adjustments do not occur frequently and historically are not material to the fair value estimates used in the Condensed Consolidated Financial Statements.
Derivatives are carried at fair value, based upon industry standard valuation techniques that use, where possible, current market-based or independently sourced pricing inputs, such as interest rates, currency exchange rates, or implied volatility.
Debt is carried at outstanding principal balance, less any unamortized issuance costs, discount or premium. Fair value is based on quoted market prices or estimates using DCF analyses based on current borrowing rates for similar types of borrowing arrangements.
The following tables present the categorization of the Company’s assets and liabilities that are measured at fair value on a recurring basis at June 30, 2025 and December 31, 2024 (in millions):

|  | Fair Value Measurements Using |
|  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) | Balance at June 30, 2025
Assets |  |  |  |  |  |  |
Money market funds (1) |  | $ | 4,129 |  |  | $ | — |  |  | $ | — |  | $ | 4,129 |
Other investments |  |  |  |  |  |  |
Government bonds |  | $ | — |  |  | $ | 1 |  |  | $ | — |  | $ | 1 |
Derivatives (2) |  |  |  |  |  |  |
Gross foreign exchange contracts |  | $ | — |  |  | $ | 63 |  |  | $ | — |  | $ | 63 |
Liabilities |  |  |  |  |  |  |
Derivatives (2) |  |  |  |  |  |  |
Gross foreign exchange contracts |  | $ | — |  |  | $ | 32 |  |  | $ | — |  | $ | 32 |

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|  | Fair Value Measurements Using |
|  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) | Balance at December 31, 2024
Assets |  |  |  |  |  |  |
Money market funds (1) |  | $ | 3,419 |  |  | $ | — |  |  | $ | — |  | $ | 3,419 |
Other investments |  |  |  |  |  |  |
Government bonds |  | $ | — |  |  | $ | 1 |  |  | $ | — |  | $ | 1 |
Derivatives (2) |  |  |  |  |  |  |
Gross foreign exchange contracts |  | $ | — |  |  | $ | 40 |  |  | $ | — |  | $ | 40 |
Liabilities |  |  |  | 0 |  |  |
Derivatives (2) |  |  |  |  |  |  |
Gross foreign exchange contracts |  | $ | — |  |  | $ | 16 |  |  | $ | — |  | $ | 16 |

(1)Included within Fiduciary assets or Short-term investments in the Condensed Consolidated Statements of Financial Position, depending on their nature and initial maturity.
(2)Refer to Note 13 “Derivatives and Hedging” for additional information regarding the Company’s derivatives and hedging activity.
There were no transfers of assets or liabilities between fair value hierarchy levels in the three and six months ended June 30, 2025 or 2024. The Company recognized no realized or unrealized gains or losses in the Condensed Consolidated Statements of Income during the three and six months ended June 30, 2025 or 2024 related to assets and liabilities measured at fair value using unobservable inputs.
The fair value of debt is classified as Level 2 of the fair value hierarchy. The following table provides the carrying value and fair value for the Company’s term debt (in millions):

| June 30, 2025 |  | December 31, 2024
| Carrying Value |  | Fair Value |  | Carrying Value |  | Fair Value
Current portion of long-term debt | $ | 1,334 |  |  | $ | 1,335 |  |  | $ | 749 |  |  | $ | 744 |
Long-term debt | $ | 15,451 |  |  | $ | 14,806 |  |  | $ | 16,265 |  |  | $ | 15,308 |

15. Claims, Lawsuits, and Other Contingencies
Legal
Aon and its subsidiaries are subject to numerous claims, tax assessments, lawsuits, and proceedings that arise in the ordinary course of business, which frequently include E&O claims. The damages claimed in these matters are or may be substantial, including, in many instances, claims for punitive, treble, or extraordinary damages. While Aon maintains meaningful E&O insurance and other insurance programs to provide protection against certain losses that arise in such matters, Aon has exhausted or materially depleted its coverage under some of the policies that protect the Company and, consequently, is self-insured or materially self-insured for some claims, including coverage from Aon’s self-insurance program. Accruals for these exposures, and related insurance receivables, when applicable, are included in the Condensed Consolidated Statements of Financial Position and have been recognized in Other general expense in the Condensed Consolidated Statements of Income to the extent that losses are deemed probable and are reasonably estimable. These amounts are adjusted from time to time as developments warrant. Matters that are not probable and reasonably estimable are not accrued for in the financial statements.
The Company’s contingencies and exposures are subject to significant uncertainties, and the determination of likelihood of a loss and estimating any such loss can be complex. The Company is therefore, in certain matters, unable to estimate the range of reasonably possible loss. Although management at present believes that the ultimate outcome of such matters, individually or in the aggregate, will not have a material adverse effect on the consolidated financial position of Aon, legal proceedings are subject to inherent uncertainties and unfavorable rulings or other events. Unfavorable resolutions could include substantial monetary or punitive damages imposed on Aon or its subsidiaries. If unfavorable outcomes of these matters were to occur, future results of operations or cash flows for any particular quarterly or annual period could be materially adversely affected. Certain significant legal proceedings involving us or our subsidiaries are described below.
Current Matters
Aon faces legal action arising out of a fatal plane crash in November 2016. Aon U.K. Limited placed an aviation civil liability reinsurance policy for the Bolivian insurer of the airline. After the crash, the insurer determined that there was no coverage
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under the airline’s insurance policy due to the airline’s breach of various policy conditions. In November 2018, the owner of the aircraft filed a claim in Bolivia against Aon, the airline, the insurer and the insurance broker. The claim is for $16 million plus any liability the owner has to third parties. In November 2019, a federal prosecutor in Brazil filed a public civil action naming three Aon entities as defendants, along with the airline, the insurer and the lead reinsurer. That claim seeks pecuniary damages for families affected by the crash in the sum of $300 million; or, in the alternative, $50 million; or, in the alternative, $25 million; plus “moral damages” of an equivalent sum. Separately, in March 2020, the Brazilian Federal Senate invited Aon to give evidence to a Parliamentary Commission of Inquiry in an investigation into the accident. Aon cooperated with that inquiry. In August 2020, 43 individuals (surviving passengers and estates of the deceased) filed a motion in the Circuit Court of the 11th Judicial Circuit in and for Miami-Dade County, Florida, seeking permission to commence proceedings against Aon (and the insurer and reinsurers) for claims totaling $844 million. In December 2022, the High Court in England granted an anti-suit injunction, restricting the 43 individuals who previously filed a motion in the Circuit Court of the 11th Judicial Circuit in and for Miami Dade County, Florida, from continuing litigation in the Circuit Court of the 11th Judicial Circuit against Aon. In June 2025, the 43 individuals filed a counterclaim against Aon in the UK seeking damages. The claim is alleged to be governed in the alternative by the laws of three different jurisdictions and asserts damages in the amount of $16.7 million. The claim alleges that certain aspects of the damages have yet to be calculated. Aon believes that it has meritorious defenses and intends to vigorously defend itself against the remaining claims.
Certain of the Company’s clients and counterparties have initiated or indicated that they may initiate legal proceedings against the Company following allegations in July 2023 that fraudulent letters of credit were issued in the name of third-party banks in connection with transactions for which capital was arranged by Vesttoo Ltd. (“Vesttoo”). Vesttoo was one of the third parties that identified capital providers to collateralize insurance and reinsurance obligations of the Company’s clients and counterparties, including in connection with property and casualty insurance, cyber insurance, and collateral protection insurance. In certain transactions in which Vesttoo identified third party capital providers to collateralize reinsurance obligations, including transactions in which the Company or its affiliates provided brokerage or other services, some letters of credit from third party banks are alleged to have been fraudulent. The pending or threatened legal proceedings against the Company by clients and counterparties – including by the liquidating trust formed to pursue claims on behalf of the Vesttoo bankruptcy estate – allege, among other theories of liability, that in certain circumstances the Company failed to comply with its alleged duty to procure appropriate letters of credit. In particular, on November 30, 2023, Clear Blue Insurance Company and certain of its affiliates filed a lawsuit in New York State Supreme Court against Aon plc and Aon Insurance Managers (Bermuda) Ltd. alleging such claims. While Aon has settled and/or is in discussions to settle certain claims, Aon believes that it has meritorious defenses and intends to vigorously defend itself against those claims that are not settled. In the fourth quarter of 2023, the Company recognized actual or anticipated legal settlement expenses in connection with these matters of $197 million, of which a potentially significant amount may be recoverable in future periods. Aon has sought and will continue to seek recourse against responsible third parties where appropriate. In addition, in August 2023, joint provisional liquidators were appointed over one of the Company’s subsidiaries in Bermuda with respect to segregated accounts that were impacted by the allegedly fraudulent letters of credit. The joint provisional liquidators were released from their appointment on July 3, 2024. Aon continues to cooperate with regulators in Bermuda, and other regulatory authorities could initiate investigations or proceedings against the Company or third parties.
Guarantees and Indemnifications
The Company provides a variety of guarantees and indemnifications to its customers and others. The maximum potential amount of future payments represents the notional amounts that could become payable under the guarantees and indemnifications if there were a total default by the guaranteed parties, without consideration of possible recoveries under recourse provisions or other methods. These amounts may bear no relationship to the expected future payments, if any, for these guarantees and indemnifications. Any anticipated amounts payable are included in the Condensed Consolidated Financial Statements, and are recorded at fair value.
The Company expects that, as prudent business interests dictate, additional guarantees and indemnifications may be issued from time to time.
Guarantee of Registered Securities
On June 22, 2023, Aon plc, Aon Global Limited, Aon Global Holdings plc, Aon Corporation, and Aon North America, Inc., and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Trustee”), as applicable, entered into supplemental indentures, each dated June 22, 2023, amending each of the following indentures (as amended, supplemented or modified from time to time) to add for the benefit of the holders of the instruments issued thereunder a full and unconditional guarantee of Aon North America, Inc. thereunder: (i) Second Amended and Restated Indenture, dated April 1, 2020, among Aon Corporation, Aon plc, Aon Global Limited, Aon Global Holdings plc and the Trustee (amending and restating the Amended and Restated Indenture, dated April 2, 2012, amending and restating the Indenture, dated January 13, 1997); (ii) Second Amended and Restated Indenture, dated April 1, 2020, among Aon Corporation, Aon plc, Aon Global Limited, Aon Global Holdings plc and
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the Trustee (amending and restating the Amended and Restated Indenture, dated April 2, 2012, amending and restating the Indenture, dated September 10, 2010); (iii) Amended and Restated Indenture, dated April 1, 2020, among Aon plc, Aon Corporation, Aon Global Limited, Aon Global Holdings plc and the Trustee (amending and restating the Indenture, dated December 12, 2012); (iv) Second Amended and Restated Indenture, dated April 1, 2020, among Aon plc, Aon Corporation, Aon Global Limited, Aon Global Holdings plc and the Trustee (amending and restating the Amended and Restated Indenture, dated May 20, 2015, amending and restating the Indenture, dated May 24, 2013); (v) Amended and Restated Indenture, dated April 1, 2020, among Aon plc, Aon Corporation, Aon Global Limited, Aon Global Holdings plc and the Trustee (amending and restating the Indenture, dated November 13, 2015); and (vi) Amended and Restated Indenture, dated April 1, 2020, among Aon Corporation, Aon plc, Aon Global Limited, Aon Global Holdings plc and the Trustee (amending and restating the Indenture, dated December 3, 2018).
On February 28, 2024, Aon plc, Aon Corporation, Aon Global Holdings plc, and Aon Global Limited (together with Aon plc, Aon Corporation and Aon Global Holdings, plc, the “Guarantors”), Aon North America, Inc. and the Trustee entered into an indenture and first supplemental indenture, each dated March 1, 2024, to add for the benefit of the holders of the instruments issued thereunder a full and unconditional guarantee by the Guarantors of the obligations of Aon North America, Inc. thereunder.
Letters of Credit
Aon has entered into a number of arrangements whereby the Company’s performance on certain obligations is guaranteed by a third party through the issuance of LOCs. The Company had total LOCs outstanding of approximately $126 million at June 30, 2025, and $124 million at December 31, 2024. These LOCs cover the beneficiaries related to certain of Aon’s U.S. and Canadian secure non-qualified pension plan schemes, reinsurance obligations related to Aon’s own E&O liability insurance program, and secure deductible retentions for Aon’s own workers compensation program. The Company has also obtained LOCs to cover contingent payments for taxes and other business obligations to third parties, and other guarantees for miscellaneous purposes at its international subsidiaries.
Premium Payments
The Company has certain contractual contingent guarantees for premium payments owed by clients to certain insurance companies. The maximum exposure with respect to such contractual contingent guarantees was approximately $161 million at June 30, 2025 compared to $162 million at December 31, 2024.
16. Segment Information
Reportable segments were determined using a management approach. They are consistent with how the CODM assesses the performance of the Company and allocates resources based on two segments: Risk Capital and Human Capital. This segmentation allows the CODM, who is our Chief Executive Officer and President, to align the assessment of performance and allocation of resources, based on segment operating income and operating margin, with how the Company addresses client need, accelerating its Aon United strategy through growth in Risk Capital and Human Capital and maximizing value for Aon and its shareholders.
Risk Capital supports clients through its Commercial Risk and Reinsurance solution lines. Commercial Risk includes insurance and specialty brokerage, global risk consulting, captives management, and Affinity programs. Reinsurance includes treaty reinsurance, facultative reinsurance, Strategy and Technology Group, and capital markets.
Human Capital supports clients through its Health and Wealth solution lines. Health includes consulting and brokerage, consumer benefits solutions, and talent advisory services. Wealth includes retirement consulting, pension administration, and investments consulting. Refer to Note 3 “Revenue from Contracts with Customers” for information on revenue by principal service line.
The Company does not present assets by reportable segment and this information is not used by the CODM to assess the performance of, or allocate resources to the Company’s reportable segments. As such, segment assets are not provided to the CODM.
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The following tables include information about our reportable segments, including total segment revenue, consolidated revenue, segment operating income, and income before income taxes:

| Three Months Ended June 30,
| Risk Capital |  | Human Capital |  | Corporate/Eliminations |  | Total Consolidated
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenue (1) | $2,866 |  | $2,650 |  | $1,291 |  | $1,125 |  | $(2) |  | $(15) |  | $4,155 |  | $3,760
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation and benefits | 1,541 |  | 1,390 |  | 796 |  | 710 |  | 23 |  | 30 |  | 2,360 |  | 2,130
Information technology | 88 |  | 93 |  | 45 |  | 39 |  | 3 |  | — |  | 136 |  | 132
Premises | 54 |  | 54 |  | 30 |  | 28 |  | 1 |  | — |  | 85 |  | 82
Other expenses (2) | 319 |  | 329 |  | 303 |  | 258 |  | 93 |  | 173 |  | 715 |  | 760
Total operating expenses | 2,002 |  | 1,866 |  | 1,174 |  | 1,035 |  | 120 |  | 203 |  | 3,296 |  | 3,104
Operating income | $864 |  | $784 |  | $117 |  | $90 |  | $(122) |  | $(218) |  | $859 |  | $656
Operating margin | 30.1% |  | 29.6% |  | 9.1% |  | 8.0% |  |  |  |  |  | 20.7% |  | 17.4%
Non-operating expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest income |  |  |  |  |  |  |  |  |  |  |  |  | — |  | 31
Interest expense |  |  |  |  |  |  |  |  |  |  |  |  | (212) |  | (225)
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  | 56 |  | 236
Income before income taxes |  |  |  |  |  |  |  |  |  |  |  |  | $703 |  | $698

| Six Months Ended June 30,
| Risk Capital |  | Human Capital |  | Corporate/Eliminations |  | Total Consolidated
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenue (1) | $6,057 |  | $5,625 |  | $2,836 |  | $2,228 |  | $(9) |  | $(23) |  | $8,884 |  | $7,830
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation and benefits | 3,002 |  | 2,744 |  | 1,570 |  | 1,237 |  | 37 |  | 32 |  | 4,609 |  | 4,013
Information technology | 178 |  | 182 |  | 90 |  | 74 |  | 4 |  | — |  | 272 |  | 256
Premises | 106 |  | 104 |  | 59 |  | 49 |  | 2 |  | — |  | 167 |  | 153
Other expenses (2) | 710 |  | 626 |  | 597 |  | 391 |  | 209 |  | 270 |  | 1,516 |  | 1,287
Total operating expenses | 3,996 |  | 3,656 |  | 2,316 |  | 1,751 |  | 252 |  | 302 |  | 6,564 |  | 5,709
Operating income | $2,061 |  | $1,969 |  | $520 |  | $477 |  | $(261) |  | $(325) |  | $2,320 |  | $2,121
Operating margin | 34.0% |  | 35.0% |  | 18.3% |  | 21.4% |  |  |  |  |  | 26.1% |  | 27.1%
Non-operating expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest income |  |  |  |  |  |  |  |  |  |  |  |  | 5 |  | 59
Interest expense |  |  |  |  |  |  |  |  |  |  |  |  | (418) |  | (369)
Other income (expense) |  |  |  |  |  |  |  |  |  |  |  |  | 46 |  | 311
Income before income taxes |  |  |  |  |  |  |  |  |  |  |  |  | $1,953 |  | $2,122

(1)Includes fiduciary investment income of $60 million and $125 million, respectively, in Risk Capital and less than $1 million and $2 million, respectively, in Human Capital for the three and six months ended June 30, 2025. Includes fiduciary investment income of $73 million and $151 million, respectively, in Risk Capital and $2 million and $3 million, respectively, in Human Capital for the three and six months ended June 30, 2024.
(2)Includes expenses related to Depreciation of fixed assets, Amortization and impairment of intangible assets, Accelerating Aon United Program expenses, and Other general expenses.
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Revenue
Reportable segment revenue includes inter-segment revenue of less than $1 million and $5 million, respectively, for Risk Capital and $2 million and $4 million, respectively, for Human Capital for the three and six months ended June 30, 2025, compared to $10 million and $16 million, respectively, for Risk Capital and $5 million and $7 million, respectively, for Human Capital for the three and six months ended June 30, 2024. This inter-segment revenue is eliminated as a Corporate adjustment to reconcile to the Company's Consolidated Total revenue.
Segment Operating Expenses
The Company’s segment operating expenses are generally attributed to the function of the business. Segment expenses exclude governance costs, post-retirement benefits, and other costs that are not directly attributable to a specific segment. These expenses are considered corporate expenses/eliminations.
Non-operating Expenses
The Company’s non-operating income (expenses) primarily consist of Interest income, Interest expense and Other income (expense) which are not allocated to our reportable segments, as the CODM assesses performance based on operating income results. Interest income represents income earned on Cash and cash equivalents and Short-term investments. Interest expense represents the cost of debt obligations. Other income (expense) consists of equity earnings, realized gains or losses on the sale of investments, gains on the disposal of businesses, gains or losses on derivatives, and gains or losses on foreign currency remeasurement.
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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations
EXECUTIVE SUMMARY OF SECOND QUARTER 2025 FINANCIAL RESULTS
Aon plc is a leading global professional services firm providing a broad range of Risk Capital and Human Capital solutions. Through our experience, global reach, and comprehensive analytics, we help clients meet rapidly changing, increasingly complex, and interconnected challenges related to risk and people. We are committed to accelerating innovation to address unmet and evolving client needs so that our clients are better informed, better advised, and able to make better decisions to protect and grow their business. Management remains focused on strengthening Aon and uniting the firm with a portfolio of Risk Capital and Human Capital capabilities enabled by data and analytics and a united operating model to deliver additional insight, connectivity, and efficiency.
Financial Results
The following is a summary of our second quarter of 2025 financial results.
•Revenue increased $395 million, or 11%, to $4.2 billion compared to the prior year period. The increase reflects 6% organic revenue growth, the contribution from NFP and a 1% favorable impact from foreign currency translation. Risk Capital revenue increased $216 million, or 8%, to $2.9 billion and Human Capital revenue increased $166 million, or 15%, to $1.3 billion compared to the prior year period. For the first six months of 2025, Revenue increased $1.1 billion, or 13%, to $8.9 billion compared to the prior year period. The increase reflects the contribution from NFP, 5% organic revenue growth, and a 1% unfavorable impact from foreign currency translation. Risk Capital revenue increased $432 million, or 8%, to $6.1 billion and Human Capital revenue increased $608 million, or 27%, to $2.8 billion compared to the prior year period.
•Operating expenses increased $192 million, or 6%, to $3.3 billion compared to the prior year period due primarily to the inclusion of NFP’s ongoing operating expenses, an increase in intangible asset amortization associated with the NFP acquisition and an increase in expense associated with 6% organic revenue growth and investments in long-term growth, partially offset by transaction costs incurred in the prior year period, lower Accelerating Aon United program expense and $35 million of net restructuring savings. Risk Capital operating expenses increased $136 million, or 7%, to $2.0 billion and Human Capital operating expenses increased $139 million, or 13%, to $1.2 billion compared to the prior year period. For the first six months of 2025, Operating expenses increased $855 million, or 15%, to $6.6 billion compared to the prior year period due primarily to the inclusion of NFP’s ongoing expenses, an increase in intangible asset amortization associated with the NFP acquisition, an increase in expense associated with 5% organic revenue growth and investments in long-term growth, partially offset by transaction costs incurred in the prior year period and $75 million of net restructuring savings. Ris k Capital operating expenses increased $340 million, or 9%, to $4.0 billion and Human Capital operating expenses increased $565 million, or 32%, to $2.3 billion compared to the prior year period.
•Operating margin increased to 20.7% from 17.4% in the prior year period, driven by organic revenue growth of 6% and $35 million of net restructuring savings, partially offset by the addition of NFP and an increase in operating expenses as previously described. Risk Capital operating margin increased to 30.1% from 29.6% and Human Capital operating margin increased to 9.1% from 8.0% compared to the prior year period. For the first six months of 2025, Operating margin decreased to 26.1% from 27.1% in the prior year period, driven primarily by the addition of NFP and an increase in operating expenses as previously described, partially offset by organic revenue growth of 5% and $75 million of net restructuring savings. Risk Capital operating margin decreased to 34.0% from 35.0% and Human Capital operating margin decreased to 18.3% from 21.4% compared to the prior year period.
•Due to the factors set forth above, Net income increased $56 million, or 10%, to $594 million compared to the prior year period. For the first six months of 2025, Net income decreased $55 million, or 3%, to $1.6 billion compared to the prior year period.
•Diluted earnings per share was $2.66 compared to $2.46 per share for the prior year period. For the first six months of 2025, Diluted earnings per share was $7.10 compared to $7.72 per share for the prior year period.
•Cash flows provided by operating activities was $936 million for the first six months of 2025, an increase of $114 million, or 14%, from $822 million in the prior year period, primarily due to strong adjusted operating income growth and days sales outstanding improvements, partially offset by higher payments related to incentive compensation, interest, and restructuring.
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We focus on four key metrics that are not presented in accordance with U.S. GAAP that we communicate to shareholders: organic revenue growth, adjusted operating margin, adjusted diluted earnings per share, and free cash flow. These non-GAAP metrics should be viewed in addition to, not instead of, our Condensed Consolidated Financial Statements. The following is our measure of performance against these four metrics for the second quarter of 2025:
•Organic revenue growth, a non-GAAP measure defined under the caption “Review of Consolidated Results — Organic Revenue Growth,” was 6% for the second quarter of 2025 and 5% for the first six months of 2025, driven by net new business and ongoing strong retention.
•Adjusted operating margin, a non-GAAP measure defined under the caption “Review of Consolidated Results — Adjusted Operating Margin,” was 28.2% for the second quarter of 2025 compared to 27.4% in the prior year period. The increase in adjusted operating margin primarily reflects 6% organic revenue growth and $35 million of net restructuring savings, partially offset by the addition of NFP and increased expenses. Risk Capital adjusted operating margin increased to 34.1% compared to 33.6% in the prior year period. Human Capital adjusted operating margin increased to 19.1% compared to 18.7% in the prior year period. For the first six months of 2025, adjusted operating margin was 33.6% compared to 33.8% for the prior year period. The decrease primarily reflects the addition of NFP and increased expenses, partially offset by 5% organic revenue growth and $75 million of net restructuring savings. Risk Capital adjusted operating margin remained flat at 37.9% in both periods. Human Capital adjusted operating margin increased to 27.9% compared to 27.5% in the prior year period.
•Adjusted diluted earnings per share, a non-GAAP measure defined under the caption “Review of Consolidated Results — Adjusted Diluted Earnings per Share,” was $3.49 per share for the second quarter of 2025, compared to $2.93 per share for the prior year period. For the first six months of 2025, adjusted diluted earnings per share was 9.17 per share, compared to $8.50 per share for the prior year period.
•Free cash flow, a non-GAAP measure defined under the caption “Review of Consolidated Results — Free Cash Flow,” was $816 million in the first six months of 2025, an increase of $95 million, or 13%, from $721 million in the prior year period, reflecting a $114 million increase in Cash flows from operations, primarily driven by strong operating income growth and improvements in days sales outstanding, partially offset by higher payments related to incentive compensation, interest, and restructuring, and a $19 million increase in capital expenditures.
The current macroeconomic and geopolitical environment is subject to a number of uncertainties, including geopolitical conflicts, tariffs or changes in trade policies, capital markets volatility, and inflation. These and other factors have contributed and may continue to contribute to slower or negative economic growth and may create a challenging business environment for our clients. While we remain confident in the resilience and strength of our business and financial model, due to the global nature of our business, the current macroeconomic and geopolitical environment could negatively impact our financial condition and results of operations. For more information about these risks, please see “Part I, Item 1A. Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2024.
Management of corporate sustainability risks – including those related to ESG matters – is an increasingly important priority for our clients. At Aon, helping clients manage risk - including those relating to corporate sustainability and ESG - is at the core of what we do. We offer a wide range of risk assessment, consulting, and advisory solutions, many of which are significant parts of our core business offerings, designed to address and manage corporate sustainability and ESG issues for clients, and to enable our clients to create more sustainable value.
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REVIEW OF CONSOLIDATED RESULTS
Summary of Results
Our consolidated results (unaudited) are as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue |  |  |  |  |  |  |  |
Total revenue |  | $ | 4,155 |  |  | $ | 3,760 |  |  | $ | 8,884 |  |  | $ | 7,830 |
Expenses |  |  |  |  |  |  |  |
Compensation and benefits |  | 2,360 |  |  | 2,130 |  |  | 4,609 |  |  | 4,013 |
Information technology |  | 136 |  |  | 132 |  |  | 272 |  |  | 256 |
Premises |  | 85 |  |  | 82 |  |  | 167 |  |  | 153 |
Depreciation of fixed assets |  | 47 |  |  | 45 |  |  | 93 |  |  | 89 |
Amortization and impairment of intangible assets |  | 201 |  |  | 128 |  |  | 400 |  |  | 144 |
Other general expense |  | 373 |  |  | 455 |  |  | 819 |  |  | 803 |
Accelerating Aon United Program expenses |  | 94 |  |  | 132 |  |  | 204 |  |  | 251 |
Total operating expenses |  | 3,296 |  |  | 3,104 |  |  | 6,564 |  |  | 5,709 |
Operating income |  | 859 |  |  | 656 |  |  | 2,320 |  |  | 2,121 |
Interest income |  | — |  |  | 31 |  |  | 5 |  |  | 59 |
Interest expense |  | (212) |  |  | (225) |  |  | (418) |  |  | (369) |
Other income (expense) |  | 56 |  |  | 236 |  |  | 46 |  |  | 311 |
Income before income taxes |  | 703 |  |  | 698 |  |  | 1,953 |  |  | 2,122 |
Income tax expense |  | 109 |  |  | 160 |  |  | 377 |  |  | 491 |
Net income |  | 594 |  |  | 538 |  |  | 1,576 |  |  | 1,631 |
Less: Net income attributable to redeemable and nonredeemable noncontrolling interests |  | 15 |  |  | 14 |  |  | 32 |  |  | 36 |
Net income attributable to Aon shareholders |  | $ | 579 |  |  | $ | 524 |  |  | $ | 1,544 |  |  | $ | 1,595 |
Diluted net income per share attributable to Aon shareholders |  | $ | 2.66 |  |  | $ | 2.46 |  |  | $ | 7.10 |  |  | $ | 7.72 |
Weighted average ordinary shares outstanding - diluted |  | 217.3 |  |  | 213.3 |  |  | 217.6 |  |  | 206.7 |

Our segment results (unaudited) are as follows (in millions):

| Three Months Ended June 30,
| Risk Capital |  | Human Capital |  | Corporate/Eliminations (1) |  | Total Consolidated
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenue | $ | 2,866 |  |  | $ | 2,650 |  |  | $ | 1,291 |  |  | $ | 1,125 |  |  | $ | (2) |  |  | $ | (15) |  |  | $ | 4,155 |  |  | $ | 3,760 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation and benefits | 1,541 |  |  | 1,390 |  |  | 796 |  |  | 710 |  |  | 23 |  |  | 30 |  |  | 2,360 |  |  | 2,130 |
Information technology | 88 |  |  | 93 |  |  | 45 |  |  | 39 |  |  | 3 |  |  | — |  |  | 136 |  |  | 132 |
Premises | 54 |  |  | 54 |  |  | 30 |  |  | 28 |  |  | 1 |  |  | — |  |  | 85 |  |  | 82 |
Other expenses (2) | 319 |  |  | 329 |  |  | 303 |  |  | 258 |  |  | 93 |  |  | 173 |  |  | 715 |  |  | 760 |
Total operating expenses | 2,002 |  |  | 1,866 |  |  | 1,174 |  |  | 1,035 |  |  | 120 |  |  | 203 |  |  | 3,296 |  |  | 3,104 |
Operating income | $ | 864 |  |  | $ | 784 |  |  | $ | 117 |  |  | $ | 90 |  |  | $ | (122) |  |  | $ | (218) |  |  | $ | 859 |  |  | $ | 656 |
Operating margin | 30.1 | % |  | 29.6 | % |  | 9.1 | % |  | 8.0 | % |  |  |  |  |  | 20.7 | % |  | 17.4 | %

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| Six Months Ended June 30,
| Risk Capital |  | Human Capital |  | Corporate/Eliminations (1) |  | Total Consolidated
| 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenue | $ | 6,057 |  |  | $ | 5,625 |  |  | $ | 2,836 |  |  | $ | 2,228 |  |  | $ | (9) |  |  | $ | (23) |  |  | $ | 8,884 |  |  | $ | 7,830 |
Expenses |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation and benefits | 3,002 |  |  | 2,744 |  |  | 1,570 |  |  | 1,237 |  |  | 37 |  |  | 32 |  |  | 4,609 |  |  | 4,013 |
Information technology | 178 |  |  | 182 |  |  | 90 |  |  | 74 |  |  | 4 |  |  | — |  |  | 272 |  |  | 256 |
Premises | 106 |  |  | 104 |  |  | 59 |  |  | 49 |  |  | 2 |  |  | — |  |  | 167 |  |  | 153 |
Other expenses (2) | 710 |  |  | 626 |  |  | 597 |  |  | 391 |  |  | 209 |  |  | 270 |  |  | 1,516 |  |  | 1,287 |
Total operating expenses | 3,996 |  |  | 3,656 |  |  | 2,316 |  |  | 1,751 |  |  | 252 |  |  | 302 |  |  | 6,564 |  |  | 5,709 |
Operating income | $ | 2,061 |  |  | $ | 1,969 |  |  | $ | 520 |  |  | $ | 477 |  |  | $ | (261) |  |  | $ | (325) |  |  | $ | 2,320 |  |  | $ | 2,121 |
Operating margin | 34.0 | % |  | 35.0 | % |  | 18.3 | % |  | 21.4 | % |  |  |  |  |  | 26.1 | % |  | 27.1 | %

(1)Corporate expenses/eliminations include governance costs, post-retirement benefits, and other costs that are not directly attributable to a specific segment.
(2)Includes expenses related to Depreciation of fixed assets, Amortization and impairment of intangible assets, Accelerating Aon United Program expenses, and Other general expenses.
Revenue
Total revenue increased $395 million, or 11%, to $4.2 billion in the second quarter of 2025, compared to the prior year period. The increase reflects 6% organic revenue growth, the contribution from NFP, and a 1% favorable impact from foreign currency translation. Risk Capital revenue increased $216 million, or 8%, to $2.9 billion and Human Capital revenue increased $166 million, or 15%, to $1.3 billion in the second quarter of 2025 compared to the prior year period. For the first six months of 2025, Revenue increased $1.1 billion, or 13%, to $8.9 billion compared to the prior year period. The increase reflects the contribution from NFP, 5% organic revenue growth, and a 1% unfavorable impact from foreign currency translation. Risk Capital revenue increased $432 million, or 8%, to $6.1 billion and Human Capital revenue increased $608 million, or 27%, to $2.8 billion for the first six months of 2025 compared to the prior year period.
Risk Capital
Commercial Risk Solutions revenue increased $163 million, or 8%, to $2.2 billion in the second quarter of 2025, compared to $2.0 billion in the second quarter of 2024. Organic revenue growth was 6% in the second quarter of 2025, reflecting growth across all major geographies driven by net new business and ongoing strong retention. Performance was highlighted by strong growth globally in core P&C and strength in M&A services relative to the prior year. Market impact was modestly positive. For the first six months of 2025, revenue increased $357 million, or 9%, to $4.2 billion, compared to $3.8 billion in the first six months of 2024. Organic revenue growth was 5% in the first six months of 2025, reflecting growth across all major geographies driven by net new business and ongoing strong retention. Performance was highlighted by strong growth globally in core P&C. Results also reflect a modest tailwind from M&A services in the first six months of 2025 relative to the prior year period. Market impact was modestly positive in the first half of the year.
Reinsurance Solutions revenue increased $53 million, or 8%, to $688 million in the second quarter of 2025, compared to $635 million in the second quarter of 2024. Organic revenue growth was 6% in the second quarter of 2025, reflecting double-digit increases in insurance-linked securities and facultative placements. Results also reflect growth in treaty, driven by net new business and ongoing strong retention, partially offset by a modest unfavorable market impact. For the first six months of 2025, revenue increased $75 million, or 4%, to $1.9 billion, compared to $1.8 billion in the first six months of 2024. Organic revenue growth was 4% in the first six months of 2025, reflecting growth in treaty, driven by net new business and ongoing strong retention. Results also reflect a double-digit increase in facultative placements and insurance-linked securities. Market impact had a modest unfavorable impact in the first half of the year.
Human Capital
Health Solutions revenue increased $110 million, or 17%, to $772 million in the second quarter of 2025, compared to $662 million in the second quarter of 2024. Organic revenue growth was 6% in the second quarter of 2025, reflecting strength in core health and benefits, driven by net new business, ongoing strong retention, and a modestly positive market impact. The core performance was highlighted by double-digit growth internationally. Results also reflect strength in executive benefits and pharmacy benefits in NFP. For the first six months of 2025, revenue increased $403 million, or 29%, to $1.8 billion, compared to $1.4 billion in the first six months of 2024. Organic revenue growth was 6% in the first six months of 2025, reflecting
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strength globally in core health and benefits, driven by net new business, ongoing strong retention, and a modestly positive market impact. Strength in the core was partially offset by lower revenue in Consumer Benefits Solutions in the first six months of 2025. Talent revenue was lower in the first half of the year as strength in advisory was offset by a decline in analytics due to a change in the timing of survey data delivery.
Wealth Solutions revenue increased $56 million, or 12%, to $519 million in the second quarter of 2025, compared to $463 million in the second quarter of 2024. Organic revenue growth was 3% in the second quarter of 2025, reflecting growth in Retirement driven by advisory related to the ongoing impact of regulatory change. In Investments, results reflect strength in NFP, driven by net asset inflows and market performance. For the first six months of 2025, revenue increased $205 million, or 25%, to $1.0 billion, compared to $833 million in the first six months of 2024. Organic revenue growth was 6% in the first six months of 2025, reflecting strength in Investments, highlighted by double-digit revenue growth in NFP, driven by net asset inflows and market performance. Growth in Retirement in the first half of the year was driven by continued demand for advisory related to the ongoing impact of regulatory changes and pension de-risking.
Compensation and Benefits
Compensation and benefits expense increased $230 million, or 11%, in the second quarter of 2025 compared to the prior year period due primarily to the inclusion of operating expenses from NFP and expense associated with 6% organic revenue growth, partially offset by savings from Accelerating Aon United restructuring actions. For the first six months of 2025, compensation and benefits increased $596 million, or 15%, compared to the first six months of 2024. The increase was primarily driven by the inclusion of operating expenses from NFP and expense associated with 5% organic revenue growth, partially offset by savings from Accelerating Aon United restructuring actions.
Information Technology
Information technology, which represents costs associated with supporting and maintaining our infrastructure, increased $4 million, or 3%, in the second quarter of 2025 compared to the prior year period due primarily to the inclusion of ongoing operating expenses from NFP. For the first six months of 2025, information technology expenses increased $16 million, or 6%, compared to the first six months of 2024. The increase was due primarily to the inclusion of ongoing operating expenses from NFP.
Premises
Premises, which represents the cost of occupying offices in various locations throughout the world, increased $3 million, or 4%, in the second quarter of 2025 compared to the prior year period, due primarily to the inclusion of ongoing operating expenses from NFP. For the first six months of 2025, premises increased $14 million, or 9%, compared to the first six months of 2024. The increase was due primarily to the inclusion of ongoing operating expenses from NFP.
Depreciation of Fixed Assets
Depreciation of fixed assets primarily relates to software, leasehold improvements, furniture, fixtures, and equipment, computer equipment, buildings, and vehicles. Depreciation of fixed assets increased $2 million, or 4%, in the second quarter of 2025 compared to the prior year period. For the first six months of 2025, depreciation of fixed assets increased $4 million, or 4%, compared to the first six months of 2024.
Amortization and Impairment of Intangible Assets
Amortization and impairment of intangibles primarily relates to finite-lived customer-related and contract-based, technology, and tradename assets. Amortization and impairment of intangible assets increased $73 million to $201 million in the second quarter of 2025 compared to the prior year period due primarily to an increase in intangible assets related to the acquisition of NFP. For the first six months of 2025, amortization and impairment of intangible assets increased $256 million to $400 million, compared to the first six months of 2024. The increase was due primarily to an increase in intangible assets related to the acquisition of NFP.
Other General Expense
Other general expenses decreased $82 million, or 18%, in the second quarter of 2025 due primarily to a decrease in transaction and integration costs. For the first six months of 2025, other general expenses increased $16 million, or 2%, compared to the first six months of 2024. The increase was due primarily to the inclusion of operating expenses from NFP and integration costs, partially offset by transaction costs incurred in the prior year period.
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Accelerating Aon United Program Expenses
Accelerating Aon United Program expenses decreased $38 million in the second quarter of 2025 and decreased $47 million in the first six months of 2025, each compared to the prior year period due to lower costs related to workforce optimization and asset impairments, partially offset by higher costs related to technology and other costs.
Total Operating Expenses and Operating Income
Total operating expenses increased $192 million, or 6%, to $3.3 billion in the second quarter of 2025 due primarily to the inclusion of NFP’s ongoing operating expenses, an increase in intangible asset amortization associated with the NFP acquisition, and an increase in expense associated with 6% organic revenue growth and investments in long-term growth, partially offset by transaction costs incurred in the prior year period, lower Accelerating Aon United program expense and $35 million of net restructuring savings. Due to the factors set forth above, Total operating income increased $203 million to $859 million in the second quarter of 2025. For the first six months of 2025, Total operating expenses increased $855 million, or 15%, to $6.6 billion due primarily to intangible asset amortization associated with the NFP acquisition, an increase in 5% organic revenue growth and investments in long-term growth, partially offset by $75 million of net restructuring savings. Due to the factors set forth above, Total operating income increased $199 million to $2.3 billion for the first six months of 2025.
Risk Capital Total operating expenses increased $136 million, or 7%, to $2.0 billion in the second quarter of 2025. The increase was primarily due to an increase in Compensation and benefits. The increase in Compensation and benefits is due to the inclusion of operating expenses from NFP and an increase in expense associated with 6% organic revenue growth in both Commercial Risk Solutions and Reinsurance Solutions, partially offset by restructuring savings. Due to the factors set forth above, Risk Capital Operating income increased $80 million, or 10%, to $864 million in the second quarter of 2025. For the first six months of 2025, Risk Capital Total operating expenses increased $340 million, or 9%, to $4.0 billion. The increase was primarily due to an increase in Compensation and benefits and in Other expenses. The increase in Compensation and benefits is due to the inclusion of operating expenses from NFP and an increase in expense associated with 5% and 4% organic revenue growth in Commercial Risk Solutions and Reinsurance Solutions, respectively, partially offset by restructuring savings. The increase in Other expenses is primarily due to increased Amortization and impairment from the NFP Transaction. Due to the factors set forth above, Risk Capital Operating income increased $92 million, or 5%, to $2.1 billion for the first six months of 2025.
Human Capital Total operating expenses increased $139 million, or 13%, to $1.2 billion in the second quarter of 2025. The increase was primarily due to an increase in both Compensation and benefits and Other expenses. The increase in Compensation and benefits is due to the inclusion of operating expenses from NFP and an increase in expense associated with 6% and 3% organic revenue growth in Health Solutions and Wealth Solutions, respectively. The increase in Other expenses is primarily due to increased Amortization and impairment of intangible assets acquired from the NFP Transaction. Due to the factors set forth above, Human Capital Operating income increased $27 million, or 30%, to $117 million in the second quarter of 2025. For the first six months of 2025, Human Capital Total operating expenses increased $565 million, or 32%, to $2.3 billion. The increase was primarily due to an increase in both Compensation and benefits and Other expenses. The increase in Compensation and benefits is due to the inclusion of operating expenses from NFP and an increase in expense associated with 6% organic revenue growth in both Health Solutions and Wealth Solutions. The increase in Other expenses is primarily due to increased Amortization and impairment of intangible assets acquired from the NFP Transaction. Due to the factors set forth above, Human Capital Operating income increased $43 million, or 9%, to $520 million for the first six months of 2025.
Interest Income
Interest income represents income earned, net of expense, on operating cash balances and other income-producing investments. Interest income does not include interest earned on funds held on behalf of clients. During the second quarter of 2025, interest income decreased $31 million to an insignificant amount and for the first six months of 2025, Interest income decreased $54 million to $5 million compared to the prior year period, due primarily to interest earned in the prior year period on the investment of $5 billion of term debt proceeds which were used to fund the purchase of NFP.
Interest Expense
Interest expense, which represents the cost of our debt obligations, decreased $13 million to $212 million during the second quarter of 2025 compared to the prior year period, reflecting lower total debt. For the first six months of 2025, Interest expense increased $49 million to $418 million compared to the prior year period. The increase was driven primarily by an increase in total debt, primarily to fund the purchase of NFP.
Other Income (Expense)
Other income was $56 million for the second quarter of 2025 compared to Other income of $236 million for the second quarter of 2024. The decrease was primarily due to gains related to the sale of a business in the prior year period, partially offset
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by deferred consideration from the 2017 sale of our outsourcing business. For the first six months of 2025, Other income was $46 million compared to Other income of $311 million for the first six months of 2024. The decrease was primarily related to gains related to the sale of a business in the prior year period.
Income before Income Taxes
Income before income taxes for the second quarter of 2025 was $703 million, a 1% increase from $698 million compared to the prior year period. For the first six months of 2025, Income before income taxes was $2.0 billion, an 8% decrease from $2.1 billion for the first six months of 2024.
Income Taxes
The effective tax rate on Net income was 15.5% and 19.3% for the three and six months ended June 30, 2025, respectively. The effective tax rate on Net income was 22.9% and 23.1% for the three and six months ended June 30, 2024, respectively.
For the three and six months ended June 30, 2025, the tax rate was primarily driven by the geographical distribution of income and certain discrete items, including the tax benefit associated with the anticipated sale of certain assets and liabilities classified as held for sale and share-based payments partially offset by the unfavorable impact of other discrete items.
For the three and six months ended June 30, 2024, the tax rate was primarily driven by the geographical distribution of income and certain discrete items, including the favorable impacts of share-based payments offset by the unfavorable impact of discrete items.
Ireland, the U.K., Singapore, and many E.U. member states, among others, have enacted legislation to implement the global minimum tax that is generally consistent with the OECD’s proposed Pillar Two tax regime. There remains significant uncertainty, however, as to how Pillar Two will ultimately apply to the Company. The OECD has issued numerous guidance documents attempting to change how Pillar Two Tax operates, subject to enactment by each implementing country, and the OECD may issue additional guidance in the future. The Company is actively monitoring developments in this area and continues to evaluate the guidance and the potential impacts this may have on its global effective tax rate, results of operations, cash flows, and financial condition in 2025 and future periods.
The Company is analyzing the impacts of the One Big Beautiful Bill Act but does not anticipate a material impact on its global effective tax rate, results of operations, cash flows or financial condition in 2025 and future periods.
Net Income Attributable to Aon Shareholders
Net income attributable to Aon shareholders for the second quarter of 2025 increased to $579 million, or $2.66 per diluted share, from $524 million, or $2.46 per diluted share, in the prior year period. Net income attributable to Aon shareholders for the first six months of 2025 decreased to $1.5 billion, or $7.10 per diluted share, from $1.6 billion, or $7.72 per diluted share, in the prior year period.
Non-GAAP Metrics
In our discussion of consolidated results, we sometimes refer to certain non-GAAP supplemental information derived from consolidated financial information specifically related to organic revenue growth, adjusted operating margin, adjusted diluted earnings per share, adjusted net income attributable to Aon shareholders, adjusted net income per share, adjusted other income (expense), adjusted effective tax rate, free cash flow, and the impact of foreign exchange rate fluctuations on operating results. Management believes that these measures are important to make meaningful period-to-period comparisons and that this supplemental information is helpful to investors. Management also uses these measures to assess operating performance and performance for compensation. This non-GAAP supplemental information should be viewed in addition to, not instead of, our Condensed Consolidated Financial Statements.
Organic Revenue Growth
We use supplemental information related to Organic revenue growth to help us and our investors evaluate business growth from ongoing operations. Organic revenue growth is a non-GAAP measure that includes the impact of certain intercompany activity and excludes the impact of changes in foreign exchange rates, fiduciary investment income, acquisitions (provided that organic revenue growth includes organic growth of an acquired business as calculated assuming that the acquired business was part of the combined company for the same proportion of the relevant prior year period), divestitures (including held for sale disposal groups, if any), transfers between revenue lines, and gains or losses on derivatives accounted for as hedges. This supplemental information related to organic revenue growth represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, Total revenue in our Condensed Consolidated Financial Statements. Industry peers provide similar supplemental information about their revenue performance, although they may not make identical
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adjustments. A reconciliation of this non-GAAP measure to the reported Total revenue is as follows (in millions, except percentages):

|  | Three Months Ended June 30, |  |  |  |  |  |  |  |  |  |
|  | 2025 |  | 2024 |  | % Change |  | Less: Currency Impact (1) |  | Less: Fiduciary Investment Income (2) |  | Less: Acquisitions, Divestitures & Other |  | Organic Revenue Growth (3)
Risk Capital Revenue: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commercial Risk Solutions |  | $ | 2,178 |  |  | $ | 2,015 |  |  | 8 | % |  | 1 | % |  | — | % |  | 1 | % |  | 6 | %
Reinsurance Solutions |  | 688 |  |  | 635 |  |  | 8 |  |  | 1 |  |  | — |  |  | 1 |  |  | 6 |
Human Capital Revenue: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Health Solutions |  | 772 |  |  | 662 |  |  | 17 |  |  | — |  |  | — |  |  | 11 |  |  | 6 |
Wealth Solutions |  | 519 |  |  | 463 |  |  | 12 |  |  | 2 |  |  | — |  |  | 7 |  |  | 3 |
Eliminations |  | (2) |  |  | (15) |  |  | N/A |  | N/A |  | N/A |  | N/A |  | N/A
Total revenue |  | $ | 4,155 |  |  | $ | 3,760 |  |  | 11 | % |  | 1 | % |  | — | % |  | 4 | % |  | 6 | %

|  | Six Months Ended June 30, |  |  |  |  |  |  |  |  |  |
|  | 2025 |  | 2024 |  | % Change |  | Less: Currency Impact (1) |  | Less: Fiduciary Investment Income (2) |  | Less: Acquisitions, Divestitures & Other |  | Organic Revenue Growth (3)
Risk Capital Revenue: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commercial Risk Solutions |  | $ | 4,180 |  |  | $ | 3,823 |  |  | 9 | % |  | (1) | % |  | — | % |  | 5 | % |  | 5 | %
Reinsurance Solutions |  | 1,877 |  |  | 1,802 |  |  | 4 |  |  | — |  |  | — |  |  | — |  |  | 4 |
Human Capital Revenue: |  |  |  |  |  |  |  |  |  |  |  |  |  |
Health Solutions |  | 1,798 |  |  | 1,395 |  |  | 29 |  |  | (1) |  |  | — |  |  | 24 |  |  | 6 |
Wealth Solutions |  | 1,038 |  |  | 833 |  |  | 25 |  |  | 1 |  |  | — |  |  | 18 |  |  | 6 |
Eliminations |  | (9) |  |  | (23) |  |  | N/A |  | N/A |  | N/A |  | N/A |  | N/A
Total revenue |  | $ | 8,884 |  |  | $ | 7,830 |  |  | 13 | % |  | (1) | % |  | — | % |  | 9 | % |  | 5 | %

(1)Currency impact represents the effect on prior year period results if they were translated at current period foreign exchange rates.
(2)Fiduciary investment income for the three months ended June 30, 2025 and 2024 was $66 million and $75 million, respectively. Fiduciary investment income for the six months ended June 30, 2025 and 2024 was $133 million and $154 million, respectively.
(3)Organic revenue growth includes the impact of certain intercompany activity and excludes the impact of changes in foreign exchange rates, fiduciary investment income, acquisitions (provided that Organic revenue growth includes Organic growth of an acquired business as calculated assuming that the acquired business was part of the combined company for the same proportion of the relevant prior year period), divestitures (including held for sale disposal groups, if any), transfers between revenue lines, and gains or losses on derivatives accounted for as hedges.
Adjusted Operating Margin
We use adjusted operating margin as a non-GAAP measure of our core operating performance of the Company. Adjusted operating margin excludes the impact of certain items, as listed below, because management does not believe these expenses are the best indicators of our core operating performance. This supplemental information related to adjusted operating margin represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, Operating margin in our Condensed Consolidated Financial Statements.
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A reconciliation of this non-GAAP measure to the reported operating margin is as follows (in millions, except percentages):

| Three Months Ended June 30,
| Risk Capital |  | Human Capital |  | Corporate/Eliminations (1) |  | Total Consolidated
(millions, except percentages) | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue | $ | 2,866 |  |  | $ | 2,650 |  |  | $ | 1,291 |  |  | $ | 1,125 |  |  | $ | (2) |  |  | $ | (15) |  |  | $ | 4,155 |  |  | $ | 3,760 |
Operating income | $ | 864 |  |  | $ | 784 |  |  | $ | 117 |  |  | $ | 90 |  |  | $ | (122) |  |  | $ | (218) |  |  | $ | 859 |  |  | $ | 656 |
Amortization and impairment of intangible assets | 86 |  |  | 53 |  |  | 115 |  |  | 75 |  |  | — |  |  | — |  |  | 201 |  |  | 128 |
Change in the fair value of contingent consideration | (9) |  |  | 3 |  |  | (1) |  |  | 15 |  |  | — |  |  | — |  |  | (10) |  |  | 18 |
Accelerating Aon United Program expenses (2) | 32 |  |  | 48 |  |  | 6 |  |  | 12 |  |  | 56 |  |  | 72 |  |  | 94 |  |  | 132 |
Transaction and integration costs (3)(4) | 3 |  |  | 3 |  |  | 9 |  |  | 18 |  |  | 15 |  |  | 74 |  |  | 27 |  |  | 95 |
Adjusted operating income | $ | 976 |  |  | $ | 891 |  |  | $ | 246 |  |  | $ | 210 |  |  | $ | (51) |  |  | $ | (72) |  |  | $ | 1,171 |  |  | $ | 1,029 |
Operating margin | 30.1 | % |  | 29.6 | % |  | 9.1 | % |  | 8.0 | % |  |  |  |  |  | 20.7 | % |  | 17.4 | %
Adjusted operating margin | 34.1 | % |  | 33.6 | % |  | 19.1 | % |  | 18.7 | % |  |  |  |  |  | 28.2 | % |  | 27.4 | %

| Six Months Ended June 30,
| Risk Capital |  | Human Capital |  | Corporate/Eliminations (1) |  | Total Consolidated
(millions, except percentages) | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024 |  | 2025 |  | 2024
Revenue | $ | 6,057 |  |  | $ | 5,625 |  |  | $ | 2,836 |  |  | $ | 2,228 |  |  | $ | (9) |  |  | $ | (23) |  |  | $ | 8,884 |  |  | $ | 7,830 |
Operating income | $ | 2,061 |  |  | $ | 1,969 |  |  | $ | 520 |  |  | $ | 477 |  |  | $ | (261) |  |  | $ | (325) |  |  | $ | 2,320 |  |  | $ | 2,121 |
Amortization and impairment of intangible assets | 170 |  |  | 65 |  |  | 230 |  |  | 79 |  |  | — |  |  | — |  |  | 400 |  |  | 144 |
Change in the fair value of contingent consideration | (3) |  |  | 3 |  |  | 10 |  |  | 15 |  |  | — |  |  | — |  |  | 7 |  |  | 18 |
Accelerating Aon United Program expenses (2) | 51 |  |  | 92 |  |  | 10 |  |  | 23 |  |  | 143 |  |  | 136 |  |  | 204 |  |  | 251 |
Transaction and integration costs (3)(4) | 14 |  |  | 3 |  |  | 21 |  |  | 18 |  |  | 21 |  |  | 89 |  |  | 56 |  |  | 110 |
Adjusted operating income | $ | 2,293 |  |  | $ | 2,132 |  |  | $ | 791 |  |  | $ | 612 |  |  | $ | (97) |  |  | $ | (100) |  |  | $ | 2,987 |  |  | $ | 2,644 |
Operating margin | 34.0 | % |  | 35.0 | % |  | 18.3 | % |  | 21.4 | % |  |  |  |  |  | 26.1 | % |  | 27.1 | %
Adjusted operating margin | 37.9 | % |  | 37.9 | % |  | 27.9 | % |  | 27.5 | % |  |  |  |  |  | 33.6 | % |  | 33.8 | %

(1)Corporate expenses/eliminations include governance costs, post-retirement benefits, and other costs that are not directly attributable to a specific segment.
(2)Total charges are expected to include technology-related costs to facilitate streamlining and simplifying operations, headcount reduction costs, and costs associated with asset impairments, including real estate consolidation and technology costs.
(3)Transaction costs include advisory, legal, accounting, regulatory, and other professional or consulting fees required to complete the NFP Transaction. No transaction costs were recognized for the three and six months ended June 30, 2025. $85 million and $96 million of transaction costs were recognized for the three and six months ended June 30, 2024, respectively. Of these amounts, $79 million and $90 million were recognized, respectively, in Total operating expenses and $6 million were recognized in Other income (expense) related to the extinguishment of acquired NFP debt for the three and six months ended June 30, 2024.
(4)The NFP Transaction has and will continue to result in certain non-recurring integration costs associated with colleague severance, retention bonus awards, termination of redundant third-party agreements, costs associated with legal entity rationalization, and professional or consulting fees related to alignment of ma nagement processes and controls, as well as costs associated with the assessment of NFP information technology environment and security protocols. Aon incurred $27 million and $16 million of integration costs in the three months ended June 30, 2025 and 2024, respectively, and $56 million and $20 million of integration costs in the six months ended June 30, 2025 and 2024, respectively.
Risk Capital Adjusted operating income increased $85 million, or 10%, to $976 million in the second quarter of 2025. The increase was primarily due to organic revenue growth of 6% in both Commercial Risk Solutions and Reinsurance Solutions and the impact of NFP, partially offset by increased expenses and investments in long-term growth. Human Capital Adjusted operating income increased $36 million, or 17%, to $246 million in the second quarter of 2025. The increase was primarily due to organic revenue growth of 6% in Health Solutions and 3% in Wealth Solutions and the impact of NFP, partially offset by increased expenses and investments in long-term growth. For the first six months of 2025, Risk Capital Adjusted operating income increased $161 million, or 8%, to $2.3 billion. The increase was primarily due to organic revenue growth of 5% in Commercial Risk Solutions and 4% in Reinsurance Solutions and the impact of NFP, partially offset by increased expenses and investments in long-term growth. Human Capital Adjusted operating income increased $179 million, or 29%, to $791 million for the first six months of 2025. The increase was primarily due to organic revenue growth of 6% in both Health Solutions and Wealth Solutions and the impact of NFP, partially offset by increased expenses and investments in long-term growth.
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Adjusted Diluted Earnings per Share
We use adjusted diluted earnings per share as a non-GAAP measure of our core operating performance. Adjusted diluted earnings per share excludes the impact of certain items, as listed below, because management does not believe these expenses are the best indicators of our core operating performance. This supplemental information related to adjusted diluted earnings per share represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, diluted earnings per share in our Condensed Consolidated Financial Statements.
A reconciliation of this non-GAAP measure to reported diluted earnings per share is as follows (in millions, except per share data and percentages):

|  | Three Months Ended June 30, 2025
|  | U.S. GAAP |  | Adjustments |  | Non-GAAP Adjusted
Operating income |  | $ | 859 |  |  | $ | 312 |  |  | $ | 1,171 |
Interest income |  | — |  |  | — |  |  | — |
Interest expense |  | (212) |  |  | — |  |  | (212) |
Other income (expense) (1) |  | 56 |  |  | (88) |  |  | (32) |
Income before income taxes |  | 703 |  |  | 224 |  |  | 927 |
Income tax expense (2) |  | 109 |  |  | 44 |  |  | 153 |
Net income |  | 594 |  |  | 180 |  |  | 774 |
Less: Net income attributable to noncontrolling interests |  | 15 |  |  | — |  |  | 15 |
Net income attributable to Aon shareholders |  | $ | 579 |  |  | $ | 180 |  |  | $ | 759 |
Diluted net income per share attributable to Aon shareholders |  | $ | 2.66 |  |  | $ | 0.83 |  |  | $ | 3.49 |
Weighted average ordinary shares outstanding - diluted |  | 217.3 |  |  | — |  |  | 217.3 |
Effective tax rates (2) |  | 15.5 | % |  |  |  | 16.5 | %

|  | Three Months Ended June 30, 2024 |  |
|  | U.S. GAAP |  | Adjustments |  | Non-GAAP Adjusted |  |  |  |
Operating income |  | $ | 656 |  |  | $ | 373 |  |  | $ | 1,029 |  |  |  |  |
Interest income |  | 31 |  |  | — |  |  | 31 |  |  |  |  |
Interest expense |  | (225) |  |  | — |  |  | (225) |  |  |  |  |
Other income (expense) (3)(4) |  | 236 |  |  | (251) |  |  | (15) |  |  |  |  |
Income before income taxes |  | 698 |  |  | 122 |  |  | 820 |  |  |  |  |
Income tax expense (2) |  | 160 |  |  | 22 |  |  | 182 |  |  |  |  |
Net income |  | 538 |  |  | 100 |  |  | 638 |  |  |  |  |
Less: Net income attributable to noncontrolling interests |  | 14 |  |  | — |  |  | 14 |  |  |  |  |
Net income attributable to Aon shareholders |  | $ | 524 |  |  | $ | 100 |  |  | $ | 624 |  |  |  |  |
Diluted net income per share attributable to Aon shareholders |  | $ | 2.46 |  |  | $ | 0.47 |  |  | $ | 2.93 |  |  |  |  |
Weighted average ordinary shares outstanding - diluted |  | 213.3 |  |  | — |  |  | 213.3 |  |  |  |  |
Effective tax rates (2) |  | 22.9 | % |  |  |  | 22.2 | % |  |  |  |

44

|  | Six Months Ended June 30, 2025
|  | U.S. GAAP |  | Adjustments |  | Non-GAAP Adjusted
Operating income |  | $ | 2,320 |  |  | $ | 667 |  |  | $ | 2,987 |
Interest income |  | 5 |  |  | — |  |  | 5 |
Interest expense |  | (418) |  |  | — |  |  | (418) |
Other income (expense) (1) |  | 46 |  |  | (108) |  |  | (62) |
Income before income taxes |  | 1,953 |  |  | 559 |  |  | 2,512 |
Income tax expense (2) |  | 377 |  |  | 108 |  |  | 485 |
Net income |  | 1,576 |  |  | 451 |  |  | 2,027 |
Less: Net income attributable to noncontrolling interests |  | 32 |  |  | — |  |  | 32 |
Net income attributable to Aon shareholders |  | $ | 1,544 |  |  | $ | 451 |  |  | $ | 1,995 |
Diluted net income per share attributable to Aon shareholders |  | $ | 7.10 |  |  | $ | 2.07 |  |  | $ | 9.17 |
Weighted average ordinary shares outstanding - diluted |  | 217.6 |  |  | — |  |  | 217.6 |
Effective tax rates (2) |  | 19.3 | % |  |  |  | 19.3 | %

|  | Six Months Ended June 30, 2024 |  |
|  | U.S. GAAP |  | Adjustments |  | Non-GAAP Adjusted |  |  |  |
Operating income |  | $ | 2,121 |  |  | $ | 523 |  |  | $ | 2,644 |  |  |  |  |
Interest income |  | 59 |  |  | — |  |  | 59 |  |  |  |  |
Interest expense |  | (369) |  |  | — |  |  | (369) |  |  |  |  |
Other income (expense) (1)(3)(4) |  | 311 |  |  | (333) |  |  | (22) |  |  |  |  |
Income before income taxes |  | 2,122 |  |  | 190 |  |  | 2,312 |  |  |  |  |
Income tax expense (2) |  | 491 |  |  | 28 |  |  | 519 |  |  |  |  |
Net income |  | 1,631 |  |  | 162 |  |  | 1,793 |  |  |  |  |
Less: Net income attributable to noncontrolling interests |  | 36 |  |  | — |  |  | 36 |  |  |  |  |
Net income attributable to Aon shareholders |  | $ | 1,595 |  |  | $ | 162 |  |  | $ | 1,757 |  |  |  |  |
Diluted net income per share attributable to Aon shareholders |  | $ | 7.72 |  |  | $ | 0.78 |  |  | $ | 8.50 |  |  |  |  |
Weighted average ordinary shares outstanding - diluted |  | 206.7 |  |  | — |  |  | 206.7 |  |  |  |  |
Effective tax rates (2) |  | 23.1 | % |  |  |  | 22.4 | % |  |  |  |

(1)During the three and six months ended June 30, 2025, an $88 million and $108 million gain was recognized, respectively, compared to $82 million recognized for the six months ended June 30, 2024, which was all recognized in the first quarter of 2024. These gains are related to deferred consideration from the affiliates of The Blackstone Group L.P. and the other designated purchasers related to a divestiture completed in a prior year period.
(2)Adjusted items are generally taxed at the estimated annual effective tax rate, except for the applicable tax impact associated with changes in the fair value of contingent consideration, Accelerating Aon United Program expenses, certain transaction and integration costs related to the acquisition of NFP, certain gains from dispositions, and deferred consideration from a prior year sale of business, which are adjusted at the related jurisdictional rate. The tax adjustment also excludes interest accruals for income tax reserves related to the termination fee payment made in connection with the Company’s terminated proposed combination with Willis Towers Watson.
(3)Adjusted Other income (expense) excluded gains from dispo sitions of $257 million related to the sale of a business for the three and six months ended June 30, 2024.
(4)Adjusted Other income (expense) excluded approximately $6 million of debt extinguishment charges related to the repayment of NFP debt, which is considered a transaction related cost incurred in the second quarter of 2024.
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Free Cash Flow
We use free cash flow, defined as cash flows provided by operations less capital expenditures, as a non-GAAP measure of our core operating performance and cash-generating capabilities of our business operations. This supplemental information related to free cash flow represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, Cash provided by operating activities in our Condensed Consolidated Financial Statements. Management believes the supplemental information related to free cash flow is helpful to investors when evaluating our operating performance and liquidity results. The use of this non-GAAP measure does not imply or represent the residual cash flow for discretionary expenditures. A reconciliation of this non-GAAP measure to the reported Cash provided by operating activities is as follows (in millions):

|  | Six Months Ended June 30, |  |
|  | 2025 |  | 2024 |  |
Cash provided by operating activities |  | $ | 936 |  |  | $ | 822 |  |  |
Capital expenditures |  | (120) |  |  | (101) |  |  |
Free cash flow |  | $ | 816 |  |  | $ | 721 |  |  |

Impact of Foreign Currency Exchange Rate Fluctuations
Because we conduct business in over 120 countries, foreign exchange rate fluctuations may have a significant impact on our business. Foreign exchange rate movements may be significant and may distort true period-to-period comparisons of changes in revenue or pretax income. Therefore, to give financial statement users meaningful information about our operations, we have provided an illustration of the comparable impact of foreign currency exchange rates on our financial results. The methodology used to calculate this comparable impact isolates the impact of the change in currencies between periods by hypothetically translating the prior year quarter’s revenue, expenses, and net income using the current quarter’s foreign currency exchange rates.
Currency fluctuations had no impact and an unfavorable impact of $0.13 on net income per diluted share during the three and six months ended June 30, 2025, respectively, if prior year period results were translated at current period foreign exchange rates. Currency fluctuations had an unfavorable impact of $0.05 and an unfavorable impact of $0.04 on net income per diluted share during the three and six months ended June 30, 2024, respectively, if 2023 results were translated at 2024 rates.
Currency fluctuations had a favorable impact of $0.01 and an unfavorable impact of $0.13 on adjusted diluted earnings per share during the three and six months ended June 30, 2025, respectively, if prior year period results were translated at current period foreign exchange rates. Currency fluctuations had an unfavorable impact of $0.06 and an unfavorable impact of $0.04 on adjusted diluted earnings per share during the three and six months ended June 30, 2024, respectively, if 2023 results were translated at 2024 rates. These translations are performed for comparative and illustrative purposes only and do not impact the accounting policies or practices for amounts included in our Condensed Consolidated Financial Statements.
LIQUIDITY AND FINANCIAL CONDITION
Liquidity
Executive Summary
We believe that our balance sheet and strong cash flow provide us with adequate liquidity. Our primary sources of liquidity in the near-term include cash flows provided by operations and available cash reserves; primary sources of liquidity in the long-term include cash flows provided by operations, debt capacity available under our credit facilities, and capital markets. Our primary uses of liquidity are operating expenses and investments, capital expenditures, acquisitions, share repurchases, pension obligations, shareholder dividends, and Accelerating Aon United Program cash charges. We believe that cash flows from operations, available credit facilities, available cash reserves, and the capital markets will be sufficient to meet our liquidity needs, including principal and interest payments on debt obligations, capital expenditures, pension contributions, and anticipated working capital requirements in the next twelve months and over the long-term.
Cash on our balance sheet includes funds available for general corporate purposes, as well as amounts restricted as to their use. Funds held on behalf of clients in a fiduciary capacity are segregated and shown together with uncollected insurance premiums in Fiduciary assets in our Condensed Consolidated Statements of Financial Position, with a corresponding amount in Fiduciary liabilities.
In our capacity as an insurance broker or agent, we collect premiums from insureds and, after deducting our commission, remit the premiums to the respective insurance underwriters. We also collect claims or refunds from underwriters on behalf of insureds, which are then returned to the insureds. Unremitted insurance premiums and claims are held by us in a fiduciary
46

capacity. The levels of funds held on behalf of clients and liabilities can fluctuate significantly depending on when we collect the premiums, claims, and refunds, make payments to underwriters and insureds, and collect funds from clients and make payments on their behalf, and upon the impact of foreign currency movements. Funds held on behalf of clients, because of their nature, are generally invested in highly liquid securities with highly rated, credit-worthy financial institutions. Fiduciary assets include funds held on behalf of clients of $8.3 billion and $7.2 billion at June 30, 2025 and December 31, 2024, respectively, and fiduciary receivables of $12.4 billion and $10.3 billion at June 30, 2025 and December 31, 2024, respectively. While we earn investment income on the funds held in cash and money market funds, the funds cannot be used for general corporate purposes.
We maintain multicurrency cash pools with third-party banks in which various Aon entities participate. Individual Aon entities are permitted to overdraw on their individual accounts provided the overall global balance does not fall below zero. At June 30, 2025, cash balances of one or more non-U.S. entities may have been negative; however, the overall balance was positive.
The following table summarizes our Cash and cash equivalents, Short-term investments, and Fiduciary assets as of June 30, 2025 (in millions):

| Statement of Financial Position Classification |  |
Asset Type | Cash and Cash Equivalents |  | Short-term Investments |  | Fiduciary Assets |  | Total
Certificates of deposit, bank deposits, or time deposits | $ | 1,008 |  |  | $ | — |  |  | $ | 4,565 |  |  | $ | 5,573 |
Money market funds | — |  |  | 379 |  |  | 3,750 |  |  | 4,129 |
Cash, Short-term investments, and funds held on behalf of clients | 1,008 |  |  | 379 |  |  | 8,315 |  |  | 9,702 |
Fiduciary receivables | — |  |  | — |  |  | 12,362 |  |  | 12,362 |
Total | $ | 1,008 |  |  | $ | 379 |  |  | $ | 20,677 |  |  | $ | 22,064 |

Cash and cash equivalents and funds held on behalf of clients, including cash and cash equivalents and funds held on behalf of clients classified as held for sale, had a net increase of $991 million for the six months ended June 30, 2025 compared to a net increase of $599 million for the six months ended June 30, 2024. A summary of our cash flows provided by and used for operating, investing, and financing activities is as follows (in millions):

|  | Six Months Ended June 30,
|  | 2025 |  | 2024
Cash provided by operating activities |  | $ | 936 |  |  | $ | 822 |
Cash used for investing activities |  | (268) |  |  | (2,285) |
Cash provided by (used for) financing activities |  | (373) |  |  | 2,264 |
Effect of exchange rates on cash and cash equivalents and funds held on behalf of clients |  | 696 |  |  | (202) |
Net increase in cash and cash equivalents and funds held on behalf of clients |  | $ | 991 |  |  | $ | 599 |

Operating Activities
Net cash provided by operating activities during the six months ended June 30, 2025 was $936 million, an increase of $114 million compared to $822 million of Cash flows provided by operating activities in the prior year period. This amount represents Net income reported, generally adjusted for gains from sales of businesses, losses from sales of businesses, share-based compensation expense, depreciation expense, amortization and impairments, and other non-cash income and expenses, including pension settlement charges. Adjustments also include changes in working capital that relate primarily to the timing of payments of accounts payable and accrued liabilities, collection of receivables, and payments for Accelerating Aon United Program expenses.
Pension Contributions
Pension contributions were $54 million for the six months ended June 30, 2025, as compared to $27 million for the six months ended June 30, 2024. For the remainder of 2025, we expect to contribute approximately $34 million in cash to our pension plans, including contributions to non-U.S. pension plans, which are subject to changes in foreign exchange rates.
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Accelerating Aon United Program Expenses
In the third quarter of 2023, we initiated the Accelerating Aon United Program with the purpose of streamlining our technology infrastructure, optimizing our leadership structure and resource alignment, and reducing the real estate footprint to align to our hybrid working strategy. The Program includes technology-related costs to facilitate streamlining and simplifying operations, headcount reduction costs, and costs associated with asset impairments, including real estate consolidation and technology costs.
Program charges are recognized within the Program’s expenses on the accompanying Condensed Consolidated Statements of Income and consists of the following cost activities:
•Technology and other – includes costs associated with actions taken to rationalize certain applications and to optimize technology across the Company. These costs may include contract termination fees and other non-capitalizable costs associated with Program initiatives, which include professional service fees.
•Workforce optimization – includes costs associated with headcount reduction and other separation-related costs.
•Asset impairments – includes non-cash costs associated with impairment of assets, as they are identified, including ROU lease assets, leasehold improvements, and other capitalized assets no longer providing economic benefit.
The changes in the Company’s liabilities for the Program as of June 30, 2025 are as follows (in millions):

| Technology and other |  | Workforce optimization |  | Asset impairments |  | Total
Liability Balance as of December 31, 2024 | $ | 17 |  |  | $ | 97 |  |  | $ | — |  |  | $ | 114 |
Charges | 100 |  |  | 100 |  |  | 4 |  |  | 204 |
Cash payments | (84) |  |  | (82) |  |  | — |  |  | (166) |
Foreign currency translation and other | — |  |  | 5 |  |  | — |  |  | 5 |
Non-cash charges | (2) |  |  | (17) |  |  | (4) |  |  | (23) |
Liability balance as of June 30, 2025 | $ | 31 |  |  | $ | 103 |  |  | $ | — |  |  | $ | 134 |
Total costs incurred from inception to date | $ | 240 |  |  | $ | 400 |  |  | $ | 88 |  |  | $ | 728 |

The Program is currently expected to result in cumulative costs of $1.0 billion, consisting of approximately $0.9 billion of cash charges and approximately $0.1 billion of non-cash charges. Over the life of the program, our Risk Capital segment is expected to incur approximately $220 million of charges, while our Human Capital segment is expected to incur approximately $60 million of charges, with the remaining charges relating to corporate expenses. The Program is estimated to generate annualized expense savings of approximately $350 million by the end of 2026, largely benefiting Compensation and benefits, Information technology, and Premises on the Condensed Consolidated Statements of Income. For the three and six months ended June 30, 2025, total Program costs incurred were $94 million and $204 million, respectively. The Company expects to continue to review the implementation of elements of the Program throughout the course of the Program and, therefore, there may be changes to expected timing, estimates of expected costs and related savings. The Company realized an additional $35 million and $75 million of expense savings in the first three and six months of 2025, respectively, from Program actions, the majority of which were recognized within Compensation and benefits on the Condensed Consolidated Statements of Income.
Investing Activities
Cash flows used for investing activities were $268 million during the six months ended June 30, 2025, a decrease of $2.0 billion compared to $2.3 billion of Cash flows used for investing activities in the prior year period. Generally, the primary drivers of cash flows used for investing activities are acquisition of businesses, purchases of short-term investments, capital expenditures, and payments for investments. Generally, the primary drivers of cash flows provided by investing activities are sales of businesses, including collection of deferred consideration in connection with prior year business divestitures, sales of short-term investments, and proceeds from investments. The gains and losses corresponding to cash flows provided by proceeds from investments and used for payments for investments are primarily recognized in Other income (expense) in our Condensed Consolidated Statements of Income.
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Short-term Investments
Short-term investments increased $160 million to $379 million at June 30, 2025 compared to December 31, 2024. The majority of our investments carried at fair value are money market funds. These money market funds are held throughout the world with various financial institutions. We are not aware of any market liquidity issues that would materially impact the fair value of these investments.
Acquisitions and Dispositions of Businesses
During the first six months of 2025, we completed nine acquisitions, seven within Risk Capital and two within Human Capital. Cash consideration, net of cash and funds held on behalf of clients acquired, was $143 million, which relates to cash consideration paid in 2025 for current year acquisitions. The majority of cash consideration for the Griffiths & Armour acquisition, completed in the first quarter of 2025, was recognized as a cash outflow in the fourth quarter of 2024. During the first six months of 2024, we completed eight acquisitions, five within Risk Capital and three within Human Capital. Cash consideration, net of cash and funds held on behalf of clients acquired, was $2.8 billion, which includes $3 million related to acquisitions completed in 2023.
During the first six months of 2025, we completed one disposition within Human Capital for an insignificant cash flow impact. During the first six months of 2024, we completed three dispositions, two within Risk Capital and one within Human Capital, for $270 million, net of cash and funds held on behalf of clients. During the first six months of 2025 and 2024, a $108 million and $82 million gain was recognized, respectively, related to the deferred consideration earned for the 2017 sale of the benefits administration and business process outsourcing business. Other than this deferred consideration, there was an insignificant cash flow impact during the first six months of 2025 related to dispositions in prior periods.
Capital Expenditures
Our additions to fixed assets including capitalized software, amounted to $120 million and $101 million for the six months ended June 30, 2025 and 2024, respectively, which primarily relate to new build out and the refurbishing of office facilities, software development costs, and computer equipment purchases. In the current period, we continue to support certain technology projects to drive long-term growth and real estate projects to align with our Smart Working strategy, including projects related to our AAU restructuring program.
Financing Activities
Cash flows used for financing activities were $373 million during the six months ended June 30, 2025 compared to $2.3 billion of Cash flows provided by financing activities in the prior year period. Generally, the primary drivers of cash flow provided by financing activities are issuances of debt, changes in net fiduciary liabilities, and proceeds from issuance of shares. Generally, the primary drivers of cash flows used for financing activities are repayments of debt, share repurchases, cash paid for employee taxes on withholding shares, dividends paid to shareholders, transactions with noncontrolling interests, and other financing activities, such as payments for deferred consideration in connection with prior year business acquisitions.
Share Repurchase Program
We have a share repurchase program authorized by our Board of Directors. The Repurchase Program was established in April 2012 with $5.0 billion in authorized repurchases, and was increased by $5.0 billion in authorized repurchases in each of November 2014, June 2017, and November 2020, and by $7.5 billion in February 2022 for a total of $27.5 billion in repurchase authorizations.
The following table summarizes our share repurchase activity (in millions, except per share data):

| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Shares repurchased | 0.7 |  |  | 0.8 |  |  | 1.3 |  |  | 1.6 |
Average price per share | $ | 361.25 |  |  | $ | 298.09 |  |  | $ | 376.76 |  |  | $ | 304.20 |
Repurchase costs recorded to accumulated deficit | $ | 250 |  |  | $ | 250 |  |  | $ | 500 |  |  | $ | 500 |

At June 30, 2025, the remaining authorized amount for share repurchase under the Repurchase Program was approximately $1.8 billion. Under the Repurchase Program, the Company has repurchased a total of 173.5 million shares for an aggregate cost of approximately $25.7 billion. For further information regarding the Repurchase Program, see Part II, Item 2 of this report.
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Borrowings
Total debt at June 30, 2025 was $17.3 billion, an increase of $272 million compared to December 31, 2024. Further, commercial paper activity during the six months ended June 30, 2025 and 2024 is as follows (in millions):

|  | Three Months Ended June 30, |  | Six Months Ended June 30,
|  | 2025 |  | 2024 |  | 2025 |  | 2024
Total issuances (1) |  | $ | 2,295 |  |  | $ | 324 |  |  | $ | 3,444 |  |  | $ | 1,272 |
Total repayments |  | (2,409) |  |  | (324) |  |  | (2,964) |  |  | (1,863) |
Net issuances (repayments) |  | $ | (114) |  |  | $ | — |  |  | $ | 480 |  |  | $ | (591) |

(1)The proceeds of the commercial paper issuances are generally used for short-term working capital needs.
In May 2025, Aon Global Limited’s €500 million ($585 million at June 30, 2025 exchange rates) 2.875% Senior Notes due May 2026 were classified as Short-term debt and current portion of long-term debt in the Consolidated Statement of Financial Position as the date of maturity is in less than one year. The Company expects to use cash flow from operations and available cash on hand to repay these Senior Notes.
In December 2024, Aon Global Limited’s $750 million 3.875% Senior Notes due December 2025 were classified as Short-term debt and current portion of long-term debt in the Consolidated Statement of Financial Position as the date of maturity is in less than one year. The Company expects to use cash flow from operations and available cash on hand to repay these Senior Notes.
In June 2024, Aon Global Limited’s $600 million 3.50% Senior Notes matured and were repaid in full.
On April 25, 2024, Aon North America, Inc. drew its $2 billion delayed draw term loan and used proceeds, together with the proceeds of the notes issued on March 1, 2024 described below, to pay a portion of cash consideration in connection with the NFP Transaction, to repay certain debt of NFP, and to pay related fees and expenses. The term loan matures on April 24, 2027 and is prepayable at any time. As of June 30, 2025, Aon North America, Inc. repaid $1.2 billion of the outstanding balance. The remaining outstanding balance is $800 million.
On April 2, 2024, Aon plc announced that its wholly owned subsidiary, Randolph Acquisition Corp., commenced cash tender offers for any and all of the outstanding 6.875% Senior Notes due 2028, 4.875% Senior Secured Notes due 2028, 7.500% Senior Secured Notes due 2030 and 8.500% Senior Secured Notes due 2031, each issued by NFP Corp. (together, the “NFP Notes”), upon the terms and subject to the conditions set forth in the Offer to Purchase and Consent Solicitation Statement, dated as of April 2, 2024. The total amount tendered pursuant to the tender offers was approximately $3.3 billion, excluding premiums. On April 26, 2024, Randolph Acquisition Corp. purchased those NFP Notes that were validly tendered and not validly withdrawn prior to April 15, 2024, effecting the early settlement of the offers (the “Early Settlement”). In addition, on April 16, 2024, NFP Corp. delivered notices of redemption of all NFP Notes not validly tendered pursuant to the offers and purchased at the Early Settlement, at a purchase price equal to the price paid to holders of the NFP Notes in connection with the Early Settlement, with a redemption date of April 26, 2024. As a result of the Early Settlement of the offers and the related redemption which occurred on April 26, 2024, no NFP Notes remain outstanding. Aon plc incurred $6 million of debt extinguishment charges in the second quarter of 2024 related to costs related to the NFP Transaction.
On March 1, 2024, Aon North America, Inc. issued $600 million 5.125% Senior Notes due in March 2027, $1 billion 5.150% Senior Notes due in March 2029, $650 million 5.300% Senior Notes due in March 2031, $1.75 billion 5.450% Senior Notes due in March 2034, and $2 billion 5.750% Senior Notes due in March 2054, totaling to an aggregate amount of $6 billion. The Company intends to use the net proceeds from the offering for general corporate purposes, including a portion of which was used to pay a portion of the cash consideration in connection with the acquisition of NFP, to repay certain debt of NFP and to pay related fees and expenses.
Other Liquidity Matters
Distributable Profits
We are required under Irish law to have available “distributable profits” to make share repurchases or pay dividends to shareholders. Distributable profits are created through the earnings of the Irish parent company and, among other methods, through intercompany dividends or a reduction in share capital approved by the High Court of Ireland. Distributable profits are not linked to a U.S. GAAP reported amount (e.g., Accumulated deficit). As of June 30, 2025 and December 31, 2024, we had distributable profits in excess of $30.9 billion and $29.7 billion, respectively. We believe that we will have sufficient distributable profits for the foreseeable future.
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Revolving Credit Facilities
We expect cash generated by operations for 2025 to be sufficient to service our debt and contractual obligations, finance capital expenditures, and continue to pay dividends to our shareholders. Although cash from operations is expected to be sufficient to service these activities, we have the ability to access the commercial paper markets or borrow under our credit facilities to accommodate any timing differences in cash flows. Additionally, under current market conditions, we believe that we could access capital markets to obtain debt financing for longer-term funding, if needed.
As of June 30, 2025, we had two primary committed credit facilities outstanding: a $1.0 billion multi-currency U.S. credit facility expiring in September 2027 and a $1.0 billion multi-currency U.S. credit facility expiring in October 2028. In aggregate, these two facilities provide $2.0 billion in available credit.
Each of these primary committed credit facilities and the delayed draw term loan includes customary representations, warranties, and covenants, including financial covenants that require us to maintain specified ratios of adjusted consolidated EBITDA to consolidated interest expense and consolidated debt to adjusted consolidated EBITDA, in each case, tested quarterly. We did not have borrowings under either of these primary committed credit facilities as of June 30, 2025 and December 31, 2024, respectively. Additionally, we are in compliance with the financial covenants and all other covenants contained therein during the rolling 12 months ended June 30, 2025 and December 31, 2024, respectively.
Shelf Registration Statement
On June 22, 2023, we filed a shelf registration statement with the SEC, registering the offer and sale from time to time of an indeterminate amount of, among other securities, debt securities, preference shares, class A ordinary shares and convertible securities. Our ability to access the market as a source of liquidity is dependent on investor demand, market conditions, and other factors.
Rating Agency Ratings
The major rating agencies’ ratings of our debt at July 25, 2025 appear in the table below.

| Ratings |  |
| Senior Long-term Debt |  | Commercial Paper |  | Outlook
Standard & Poor’s | A- |  | A-2 |  | Negative
Moody’s Investor Services | Baa2 |  | P-2 |  | Stable
Fitch, Inc. | BBB+ |  | F-2 |  | Stable

Letters of Credit and Other Guarantees
We have entered into a number of arrangements whereby our performance on certain obligations is guaranteed by a third party through the issuance of a letter of credit. We had total LOCs outstanding of approximately $126 million at June 30, 2025, compared to $124 million at December 31, 2024. These LOCs cover the beneficiaries related to certain of our U.S. and Canadian secure non-qualified pension plan schemes, reinsurance obligations related to our own E&O liability insurance program, and secure deductible retentions for our own workers’ compensation program. We also have obtained LOCs to cover contingent payments for taxes and other business obligations to third parties, and other guarantees for miscellaneous purposes at our international subsidiaries.
We have certain contractual contingent guarantees for premium payments owed by clients to certain insurance companies. The maximum exposure with respect to such contractual contingent guarantees was approximately $161 million at June 30, 2025, compared to $162 million at December 31, 2024.
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Guarantee of Registered Securities
All issued and outstanding debt securities by Aon Corporation are guaranteed by Aon Global Limited, Aon plc, Aon North America, Inc., and Aon Global Holdings plc, and include the following (collectively, the “Aon Corporation Notes”):

Aon Corporation Notes
8.205% Junior Subordinated Notes due January 2027
4.50% Senior Notes due December 2028
3.75% Senior Notes due May 2029
2.80% Senior Notes due May 2030
6.25% Senior Notes due September 2040

All guarantees of Aon plc, Aon Global Limited, Aon North America, Inc., and Aon Global Holdings plc of the Aon Corporation Notes are joint and several as well as full and unconditional. Senior Notes rank pari passu in right of payment with all other present and future unsecured debt which is not expressed to be subordinate or junior in rank to any other unsecured debt of Aon Corporation. There are no subsidiaries other than those listed above that guarantee the Aon Corporation Notes.
All issued and outstanding debt securities by Aon Global Limited are guaranteed by Aon plc, Aon Global Holdings plc, Aon North America, Inc., and Aon Corporation, and include the following (collectively, the “Aon Global Limited Notes”):

Aon Global Limited Notes
3.875% Senior Notes due December 2025
2.875% Senior Notes due May 2026
4.25% Senior Notes due December 2042
4.45% Senior Notes due May 2043
4.60% Senior Notes due June 2044
4.75% Senior Notes due May 2045

All guarantees of Aon plc, Aon Global Holdings plc, Aon North America, Inc., and Aon Corporation of the Aon Global Limited Notes are joint and several as well as full and unconditional. Senior Notes rank pari passu in right of payment with all other present and future unsecured debt which is not expressed to be subordinate or junior in rank to any other unsecured debt of Aon Global Limited. There are no subsidiaries other than those listed above that guarantee the Aon Global Limited Notes.
All issued and outstanding debt securities by Aon North America, Inc. are guaranteed by Aon Global Limited, Aon plc, Aon Global Holdings plc, and Aon Corporation, and include the following (collectively, the “Aon North America, Inc. Notes”):

Aon North America, Inc. Notes
5.125% Senior Notes due March 2027
Delayed Draw Term Loan due April 2027
5.150% Senior Notes due March 2029
5.300% Senior Notes due March 2031
5.450% Senior Notes due March 2034
5.750% Senior Notes due March 2054

All guarantees of Aon Global Limited, Aon plc, Aon Global Holdings plc, and Aon Corporation of the Aon North America, Inc. Notes are joint and several as well as full and unconditional. Senior Notes rank pari passu in right of payment with all other present and future unsecured debt which is not expressed to be subordinate or junior in rank to any other unsecured debt of Aon North America, Inc. There are no subsidiaries other than those listed above that guarantee the Aon North America, Inc. Notes.
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All co-issued and outstanding debt securities by Aon Corporation and Aon Global Holdings plc (together, the “Co-Issuers”) are guaranteed by Aon plc, Aon North America, Inc., and Aon Global Limited and include the following (collectively, the “Co-Issued Notes”):

Co-Issued Notes - Aon Corporation and Aon Global Holdings plc
2.85% Senior Notes due May 2027
2.05% Senior Notes due August 2031
2.60% Senior Notes due December 2031
5.00% Senior Notes due September 2032
5.35% Senior Notes due February 2033
2.90% Senior Notes due August 2051
3.90% Senior Notes due February 2052

All guarantees of Aon plc, Aon Global Limited, and Aon North America, Inc. of the Co-Issued Notes are joint and several as well as full and unconditional. Senior Notes rank pari passu in right of payment with all other present and future unsecured debt which is not expressed to be subordinate or junior in rank to any other unsecured debt of the Co-Issuers. There are no subsidiaries other than those listed above that guarantee the Co-Issued Notes.
Aon Corporation, Aon North America, Inc., Aon Global Limited, and Aon Global Holdings plc are indirect wholly owned subsidiaries of Aon plc. Aon plc, Aon Global Limited, Aon Global Holdings plc, Aon North America, Inc., and Aon Corporation together comprise the “Obligor group”. The following tables set forth summarized financial information for the Obligor group, which reflects the financial results of Aon North America, Inc. for the year ended December 31, 2024 and for the period ended June 30, 2025.
Adjustments are made to the tables to eliminate intercompany balances and transactions between the Obligor group. Intercompany balances and transactions between the Obligor group and non-guarantor subsidiaries are presented as separate line items within the summarized financial information. These balances are presented on a net presentation basis, rather than a gross basis, as this better reflects the nature of the intercompany positions and presents the funding or funded position that is to be received or owed. No balances or transactions of non-guarantor subsidiaries are presented in the summarized financial information, including investments of the Obligor group in non-guarantor subsidiaries.

| Obligor Group
| Summarized Statement of Income Information
|  | Six Months Ended
(millions) |  | June 30, 2025
Revenue |  | $ | — |
Operating loss |  | $ | (54) |
Loss from non-guarantor subsidiaries before income taxes |  | $ | (212) |
Net loss |  | $ | (555) |
Net loss attributable to Aon shareholders |  | $ | (555) |

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| Obligor Group
| Summarized Statement of Financial Position Information
|  | As of | As of
(millions) |  | June 30, 2025 | December 31, 2024
Receivables due from non-guarantor subsidiaries |  | $ | 4,538 |  | $ | 9,611 |
Other current assets |  | 216 |  | 77 |
Total current assets |  | $ | 4,754 |  | $ | 9,688 |
Non-current receivables due from non-guarantor subsidiaries |  | $ | 261 |  | $ | 10,768 |
Other non-current assets |  | 1,534 |  | 1,393 |
Total non-current assets |  | $ | 1,795 |  | $ | 12,161 |
Payables to non-guarantor subsidiaries |  | $ | 10,616 |  | $ | 7,628 |
Other current liabilities |  | 5,093 |  | 3,309 |
Total current liabilities |  | $ | 15,709 |  | $ | 10,937 |
Non-current payables to non-guarantor subsidiaries |  | $ | 5,236 |  | $ | 9,801 |
Other non-current liabilities |  | 16,806 |  | 17,668 |
Total non-current liabilities |  | $ | 22,042 |  | $ | 27,469 |

CRITICAL ACCOUNTING POLICIES AND ESTIMATES
There have been no changes to our critical accounting policies, which include revenue recognition, pensions, goodwill and other intangible assets, contingencies, share-based payments, income taxes, Accelerating Aon United restructuring charges, and business combinations, as discussed in our Annual Report on Form 10-K for the year ended December 31, 2024.
NEW ACCOUNTING PRONOUNCEMENTS
Note 2 “Accounting Principles and Practices” to our Financial Statements contained in Part I, Item 1 of this report contains a discussion of recently issued accounting pronouncements and Securities and Exchange Commission final rules and their future potential impact on our financial results or disclosures, if determinable.
Item 3. Quantitative and Qualitative Disclosures about Market Risk
We are exposed to potential fluctuations in earnings, cash flows, and the fair values of certain of our assets and liabilities due to changes in interest rates and foreign exchange rates. To manage the risk from these exposures, we enter into a variety of derivative instruments. We do not enter into derivatives or financial instruments for trading or speculative purposes.
The following discussion describes our specific exposures and the strategies we use to manage these risks. Refer to Note 2 “Summary of Significant Accounting Principles and Practices” in the Notes to Consolidated Financial Statements in Part II, Item 8 of the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 for a discussion of our accounting policies for financial instruments and derivatives.
Foreign Exchange Risk
We are subject to foreign exchange rate risk. Our primary exposures include exchange rates between the U.S. dollar and the euro, the British pound, the Canadian dollar, the Australian dollar, the Indian rupee, and the Japanese yen. We use over-the-counter options and forward contracts to reduce the impact of foreign currency risk to our financial statements.
Additionally, some of our non-U.S. subsidiaries receive revenue in currencies that differ from their functional currencies. Most significantly, our U.K. subsidiaries earn a portion of their revenue in U.S. dollars, euro, and Japanese yen, but most of their expenses are incurred in British pounds. We generally hedge up to 45% of our U.K. subsidiaries’ expected exposures to transactions denominated in U.S. dollar, euro, and Japanese yen. We generally do not hedge exposures beyond two years.
We also use forward and option contracts to economically hedge foreign exchange risk associated with monetary balance sheet exposures, such as intercompany notes and current assets and liabilities that are denominated in a non-functional currency and are subject to remeasurement.
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The translated value of revenues and expenses from our international brokerage operations are subject to fluctuations in foreign exchange rates. A strengthening U.S. dollar has an adverse impact on our Net income attributable to shareholders, which are reported in U.S. dollars in our Condensed Consolidated Financial Statements. If we were to hypothetically translate prior year results at current quarter exchange rates, diluted earnings per share would have no comparable impact and an unfavorable $0.13 comparable impact during the three and six months ended June 30, 2025, respectively. Further, adjusted diluted earnings per share, a non-GAAP measure as defined and reconciled under the caption “Review of Consolidated Results — Adjusted Diluted Earnings Per Share,” would have a favorable $0.01 comparable impact and an unfavorable $0.13 comparable impact during the three and six months ended June 30, 2025, respectively, if we were to hypothetically translate prior year results at current quarter exchange rates.
Interest Rate Risk
Our fiduciary investment income is affected by changes in international and domestic short-term interest rates. We monitor our net exposure to short-term interest rates and, as appropriate, hedge our exposure with various derivative financial instruments. This activity primarily relates to brokerage funds held on behalf of clients in the U.S. and in continental Europe. A decrease in global short-term interest rates adversely affects our fiduciary investment income.
Item 4. Controls and Procedures
Evaluation of disclosure controls and procedures. We have conducted an evaluation of the effectiveness of the design and operation of our disclosure controls and procedures, as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), as of June 30, 2025. Based on this evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures, as of June 30, 2025, were effective at a reasonable assurance level such that the information required to be disclosed by us in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified by the SEC rules and forms, and 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.
Changes in internal control over financial reporting. There were no changes in our internal control over financial reporting (as defined in Rule 13a-15(f) under the Exchange Act) that occurred during the quarter ended June 30, 2025 that have materially affected, or that are reasonably likely to materially affect, our internal control over financial reporting.
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Part II Other Information
Item 1. Legal Proceedings
See Note 15 “Claims, Lawsuits, and Other Contingencies” to our Financial Statements contained in Part I, Item 1 of this report, which is incorporated by reference herein.
Item 1A. Risk Factors
The risk factors set forth in the “Risk Factors” section in Part I, Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2024 reflect certain risks associated with existing and potential lines of business and contain “forward-looking statements” as discussed in “Information Concerning Forward-Looking Statements” elsewhere in this report. Readers should consider them in addition to the other information contained in this report as our business, financial condition or results of operations could be adversely affected if any of these risks actually occur.
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
Issuer Purchases of Equity Securities
The following information relates to the purchase of equity securities by Aon or any affiliated purchaser during each month within the second quarter of 2025:

Period |  | Total Number of Shares Purchased |  | Average Price Paid per Share (1) |  | Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs (2) |  | Maximum Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs (1)(2)
4/1/25 - 4/30/25 |  | 224,498 |  |  | $ | 371.20 |  |  | 224,498 |  |  | $ | 1,983,936,202 |
5/1/25 - 5/31/25 |  | — |  |  | $ | — |  |  | — |  |  | $ | 1,983,936,202 |
6/1/25 - 6/30/25 |  | 467,548 |  |  | $ | 356.47 |  |  | 467,548 |  |  | $ | 1,817,269,668 |
|  | 692,046 |  |  | $ | 361.25 |  |  | 692,046 |  |  | $ | 1,817,269,668 |

(1)Does not include commissions paid to repurchase shares.
(2)The Repurchase Program was established in April 2012 with $5.0 billion in authorized repurchases and was increased by $5.0 billion in authorized repurchases in each of November 2014, June 2017, and November 2020, and by $7.5 billion in February 2022 for a total of $27.5 billion in repurchase authorizations.
Unregistered Sales of Equity Securities
We did not make any unregistered sales of equity in the second quarter of 2025.
Item 3. Defaults Upon Senior Securities
Not Applicable.
Item 4. Mine Safety Disclosures
Not Applicable.
Item 5. Other Information
Not Applicable.
Item 6. Exhibits
Exhibits — The exhibits filed with this report are listed on the attached Exhibit Index.
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Signature
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.

| Aon plc
| (Registrant)
July 25, 2025 | By: | /s/ Michael Neller
| Michael Neller
| GLOBAL CONTROLLER AND
| CHIEF ACCOUNTING OFFICER
| (Principal Accounting Officer and duly authorized officer of Registrant)

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Exhibit Index

Exhibit Number |  | Description of Exhibit
2.1 |  | Agreement and Plan of Merger, by and among Aon plc, Randolph Acquisition Corp., Randolph Merger Sub LLC, NFP Intermediate Holdings A. Corp and NFP Parent Co, LLC, dated as of December 19, 2023 (incorporated by reference to Exhibit 2.1 to Aon’s Current Report on Form 8-K filed with the SEC on December 20, 2023).
3.1 |  | Memorandum and Articles of Association of Aon plc (Incorporated by reference to Exhibit 3.1 to Aon’s Current Report on Form 8-K filed with the SEC on June 4, 2021).
10.1 |  | Amendment to International Assignment Letter, dated June 27, 2025, between Aon Corporation and Greg Case (incorporated by reference to Exhibit 10.1 to Aon’s Current Report on Form 8-K filed with the SEC on July 3, 2025).
10.2 |  | Aon plc 2011 Incentive Plan, as Amended and Restated (incorporated by reference to Exhibit 10.2 to Aon’s Current Report on Form 8-K filed with the SEC on July 3, 2025).
10.3* |  | Letter Agreement, dated August 1, 2022, between Aon Corporation and Mindy Simon.
10.4* |  | International Assignment Letter, effective July 1, 2023, between Aon Service Corporation and Mindy Simon.
10.5* |  | Amendment to International Assignment Letter, dated June 24, 2024, between Aon Service Corporation and Mindy Simon.
22.1* |  | Subsidiary Guarantors and Issuers of Guaranteed Securities.
31.1* |  | Certification of CEO.
31.2* |  | Certification of CFO.
32.1** |  | Certification of CEO Pursuant to section 1350 of Title 18 of the United States Code.
32.2** |  | Certification of CFO Pursuant to section 1350 of Title 18 of the United States Code.
101* |  | Interactive Data Files. The following materials are filed electronically with this Quarterly Report on Form 10-Q:
|  | 101.SCH XBRL Taxonomy Extension Schema Document
|  | 101.CAL XBRL Taxonomy Calculation Linkbase Document
|  | 101.DEF XBRL Taxonomy Definition Linkbase Document
|  | 101.PRE XBRL Taxonomy Presentation Linkbase Document
|  | 101.LAB XBRL Taxonomy Calculation Linkbase Document
104 |  | Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)
* Filed herewith
** Furnished herewith

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