UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q

     ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2024

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.)

Metropolitan Building, James Joyce Street, Dublin 1, Ireland	D01 K0Y8
(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 3.50% Senior Notes due 2024	AON24	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 April 25, 2024: 217,430,759

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,” “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 (including impacts from instability in the banking or commercial real estate sectors) 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.);

•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 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;

•the failure to retain, attract and develop experienced and qualified personnel;

•international risks associated with our global operations, including impacts from military conflicts or political instability, such as the ongoing Russian war in Ukraine and the Israel-Hamas conflict;

•the effects of natural or man-made 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;

•the extent to which we are exposed to certain risks, including lawsuits, related to our 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 will provide in the future;

•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 benefits of the acquisition of NFP (including anticipated revenue and growth synergies) in the expected timeframe, or at all;

•significant transaction and integration costs in connection with the acquisition of NFP or unknown or inestimable liabilities; and

•any potential adverse impact of the consummation of the acquisition of NFP on our relationships, including with suppliers, customers, employees, and regulators.

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 the “Risk Factors” section in Part I, Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2023. These factors may be revised or supplemented in our subsequent periodic filings with the SEC.

Table of Contents

PART I
	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
	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

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

Term	Definition
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
ERISA	Employee Retirement Income Security Act of 1974
ESG	Environmental, Social, and Governance
FCA	Financial Conduct Authority
GAAP	Generally Accepted Accounting Principles
GHG	Greenhouse Gas
LOC	Letter of Credit
M&A	Mergers and Acquisitions
OECD	Organisation for Economic Co-operation and Development
ROU	Right-of-Use
SEC	Securities and Exchange Commission
U.K.	United Kingdom
U.S.	United States

Part I Financial Information

Item 1. Financial Statements

Aon plc

Condensed Consolidated Statements of Income

(Unaudited)

	Three Months Ended March 31,
(millions, except per share data)	2024		2023
Revenue
Total revenue	$	4,070	$	3,871
Expenses
Compensation and benefits	1,883		1,792
Information technology	124		139
Premises	71		75
Depreciation of fixed assets	44		38
Amortization and impairment of intangible assets	16		25
Other general expense	348		329
Accelerating Aon United Program expenses	119		—
Total operating expenses	2,605		2,398
Operating income	1,465		1,473
Interest income	28		5
Interest expense	(144)		(111)
Other income (expense)	75		(25)
Income before income taxes	1,424		1,342
Income tax expense	331		263
Net income	1,093		1,079
Less: Net income attributable to noncontrolling interests	22		29
Net income attributable to Aon shareholders	$	1,071	$	1,050
Basic net income per share attributable to Aon shareholders	$	5.38	$	5.09
Diluted net income per share attributable to Aon shareholders	$	5.35	$	5.07
Weighted average ordinary shares outstanding - basic	199.1		206.1
Weighted average ordinary shares outstanding - diluted	200.1		207.1

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

6

Aon plc

Condensed Consolidated Statements of Comprehensive Income

(Unaudited) 

	Three Months Ended March 31,
(millions)	2024		2023
Net income	$	1,093	$	1,079
Less: Net income attributable to noncontrolling interests	22		29
Net income attributable to Aon shareholders	1,071		1,050
Other comprehensive income, net of tax:
Change in fair value of financial instruments	75		3
Foreign currency translation adjustments	(132)		54
Postretirement benefit obligation	26		22
Total other comprehensive income (loss)	(31)		79
Less: Other comprehensive income attributable to noncontrolling interests	—		—
Total other comprehensive income (loss) attributable to Aon shareholders	(31)		79
Comprehensive income attributable to Aon shareholders	$	1,040	$	1,129

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

7

Aon plc

Condensed Consolidated Statements of Financial Position

	(Unaudited)
(millions, except nominal value)	March 31, 2024		December 31, 2023
Assets
Current assets
Cash and cash equivalents	$	995	$	778
Short-term investments	5,413		369
Receivables, net	4,035		3,254
Fiduciary assets	17,161		16,307
Other current assets	1,020		996
Total current assets	28,624		21,704
Goodwill	8,302		8,414
Intangible assets, net	217		234
Fixed assets, net	590		638
Operating lease right-of-use assets	628		650
Deferred tax assets	1,254		1,195
Prepaid pension	627		618
Other non-current assets	525		506
Total assets	$	40,767	$	33,959
Liabilities and equity (deficit)
Liabilities
Current liabilities
Accounts payable and accrued liabilities	$	1,925	$	2,262
Short-term debt and current portion of long-term debt	606		1,204
Fiduciary liabilities	17,161		16,307
Other current liabilities	2,146		1,878
Total current liabilities	21,838		21,651
Long-term debt	15,916		9,995
Non-current operating lease liabilities	611		641
Deferred tax liabilities	129		115
Pension, other postretirement, and postemployment liabilities	1,198		1,225
Other non-current liabilities	1,103		1,074
Total liabilities	40,795		34,701
Equity (deficit)
Ordinary shares - $0.01 nominal value      Authorized: 500.0 shares (issued: 2024 - 198.6; 2023 - 198.6)	2		2
Additional paid-in capital	6,969		6,944
Accumulated deficit	(2,700)		(3,399)
Accumulated other comprehensive loss	(4,404)		(4,373)
Total Aon shareholders' deficit	(133)		(826)
Noncontrolling interests	105		84
Total deficit	(28)		(742)
Total liabilities and equity (deficit)	$	40,767	$	33,959

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

8

Aon plc

Condensed Consolidated Statements of Shareholders’ Equity (Deficit)

(Unaudited) 

(millions)	Shares	Ordinary Shares and Additional Paid-in Capital		Accumulated Deficit		Accumulated  Other Comprehensive Loss, Net of Tax		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 noncontrolling interests	—	(1)		—		—		—		(1)
Dividends paid to noncontrolling interests on subsidiary common stock	—	—		—		—		(1)		(1)
Balance at March 31, 2024	198.6	$	6,971	$	(2,700)	$	(4,404)	$	105	$	(28)

(millions)	Shares	Ordinary Shares and Additional Paid-in Capital		Accumulated Deficit		Accumulated  Other Comprehensive Loss, Net of Tax		Non- controlling Interests		Total
Balance at January 1, 2023	205.4	$	6,866	$	(2,772)	$	(4,623)	$	100	$	(429)
Net income	—	—		1,050		—		29		1,079
Shares issued - employee stock compensation plans	0.9	(131)		(1)		—		—		(132)
Shares repurchased	(1.8)	—		(550)		—		—		(550)
Share-based compensation expense	—	127		—		—		—		127
Dividends to shareholders ($0.56 per share)	—	—		(115)		—		—		(115)
Net change in fair value of financial instruments	—	—		—		3		—		3
Net foreign currency translation adjustments	—	—		—		54		—		54
Net postretirement benefit obligation	—	—		—		22		—		22
Dividends paid to noncontrolling interests on subsidiary common stock	—	—		—		—		(1)		(1)
Balance at March 31, 2023	204.5	$	6,862	$	(2,388)	$	(4,544)	$	128	$	58

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

9

Aon plc

Condensed Consolidated Statements of Cash Flows

(Unaudited)

	Three Months Ended March 31,
(millions)	2024		2023
Cash flows from operating activities
Net income	$	1,093	$	1,079
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation of fixed assets	44		38
Amortization and impairment of intangible assets	16		25
Share-based compensation expense	130		127
Deferred income taxes	(76)		(70)
Other, net	(82)		—
Change in assets and liabilities:
Receivables, net	(826)		(664)
Accounts payable and accrued liabilities	(343)		(443)
Accelerating Aon United Program liabilities	34		—
Current income taxes	163		126
Pension, other postretirement and postemployment liabilities	(12)		(9)
Other assets and liabilities	168		234
Cash provided by operating activities	309		443
Cash flows from investing activities
Proceeds from investments	118		13
Purchases of investments	(56)		(11)
Net sales (purchases) of short-term investments - non fiduciary	(5,046)		280
Acquisition of businesses, net of cash and funds held on behalf of clients	(4)		(2)
Sale of businesses, net of cash and funds held on behalf of clients	75		1
Capital expenditures	(48)		(76)
Cash provided by (used for) investing activities	(4,961)		205
Cash flows from financing activities
Share repurchase	(250)		(550)
Proceeds from issuance of shares	25		25
Cash paid for employee taxes on withholding shares	(130)		(157)
Commercial paper issuances, net of repayments	(591)		(173)
Issuance of debt	5,942		744
Increase in fiduciary liabilities, net of fiduciary receivables	394		636
Cash dividends to shareholders	(123)		(115)
Noncontrolling interests and other financing activities	(6)		(6)
Cash provided by financing activities	5,261		404
Effect of exchange rates on cash and cash equivalents and funds held on behalf of clients	(146)		58
Net increase in cash and cash equivalents and funds held on behalf of clients	463		1,110
Cash, cash equivalents and funds held on behalf of clients at beginning of period	7,722		7,076
Cash, cash equivalents and funds held on behalf of clients at end of period	$	8,185	$	8,186
Reconciliation of cash and cash equivalents and funds held on behalf of clients:
Cash and cash equivalents	$	995	$	1,119
Cash and cash equivalents and funds held on behalf of clients classified as held for sale	73		—
Funds held on behalf of clients	7,117		7,067
Total cash and cash equivalents and funds held on behalf of clients	$	8,185	$	8,186
Supplemental disclosures:
Interest paid	$	95	$	79
Income taxes paid, net of refunds	$	244	$	206

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

10

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, 2023. The results for the three months ended March 31, 2024 are not necessarily indicative of operating results that may be expected for the full year ending December 31, 2024.

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 Reportable Segment Disclosures

In November 2023, the FASB issued new accounting guidance, requiring new segment disclosures under ASC 280, Segment Reporting, including disclosure of significant segment expense categories and amounts that are regularly reported to the CODM and included in the segment’s profit or loss. Additionally, all disclosure requirements under ASC 280, including new requirements under this new guidance, will be required on an interim basis. The new guidance is effective for Aon for the year ended December 31, 2024 and interim periods thereafter, with early adoption permitted. An entity will apply the new guidance on a retrospective basis for all periods presented. The Company is currently evaluating the impact the guidance will have on the Notes to Consolidated Financial Statements.

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 Aon for the year ended December 31, 2025, with early adoption permitted. The Company is evaluating the period of adoption and transition approach, as well as the impact the disclosures will have on the Notes to Consolidated Financial Statements.

11

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 will require the Company to provide certain climate-related information in Item 7, Management’s Discussion and Analysis 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 greenhouse gas (“GHG”) emissions. Additionally, within the Notes to Consolidated Financial Statements, the Company will be required to disclose the financial statement effects of severe weather events and other natural conditions. The final rules are effective for Aon for the year-ended December 31, 2025, with the exception of GHG emissions disclosures which are effective for Aon for the year-ended December 31, 2026. After the adoption of the final rules, the final rules became subject to several legal challenges, and on April 4, 2024 the SEC voluntarily stayed the final rules pending judicial review. The Company is currently evaluating the impact that the guidance will have on our disclosures and will monitor the judicial process for 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 March 31,
	2024		2023
Commercial Risk Solutions	$	1,808	$	1,778
Reinsurance Solutions	1,167		1,077
Health Solutions	733		671
Wealth Solutions	370		350
Eliminations	(8)		(5)
Total revenue	$	4,070	$	3,871

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 March 31,
	2024		2023
United States	$	1,512	$	1,495
Americas other than United States	323		301
United Kingdom	583		554
Ireland	33		30
Europe, Middle East, & Africa other than United Kingdom and Ireland	1,209		1,102
Asia Pacific	410		389
Total revenue	$	4,070	$	3,871

12

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 March 31,
	2024		2023
Balance at beginning of period	$	370	$	355
Additions	380		362
Amortization	(478)		(462)
Impairment	—		—
Foreign currency translation and other	(3)		2
Balance at end of period	$	269	$	257

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 March 31,
	2024		2023
Balance at beginning of period	$	195	$	185
Additions	14		10
Amortization	(13)		(12)
Impairment	—		—
Foreign currency translation and other	(2)		—
Balance at end of period	$	194	$	183

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”) with the purpose of streamlining the Company’s technology infrastructure, optimizing its leadership structure and resource alignment, and reducing the real estate footprint to align to its hybrid working strategy. The Program will 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.

Program charges are recognized within Accelerating Aon United Program 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 Program is currently expected to result in cumulative costs of approximately $1.0 billion, consisting of approximately $900 million of cash charges and approximately $100 million of non-cash charges. For the three months ended March 31, 2024, total Program costs incurred were $119 million. 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’s unpaid liabilities for charges under the Program are generally included in Accounts payable and accrued 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 March 31, 2024 are as follows (in millions):

	Technology and other		Workforce optimization		Asset impairments		Total
Liability Balance as of January 1, 2024	$	14	$	86	$	—	$	100
Charges	19		64		36		119
Cash payments	(12)		(25)		—		(37)
Foreign currency translation and other	—		(1)		—		(1)
Non-cash charges	(7)		(5)		(36)		(48)
Liability balance as of March 31, 2024	$	14	$	119	$	—	$	133
Total costs incurred from inception to date	$	33	$	167	$	54	$	254

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 March 31, 2024, Cash and cash equivalents and Short-term investments were $6.4 billion compared to $1.1 billion at December 31, 2023, an increase of $5.3 billion primarily related to net proceeds from debt offerings to be used for general corporate purposes, including to fund the acquisition of NFP. Refer to Note 9 “Debt” for further information. Of the total balances, $112 million and $120 million were restricted as to their use at March 31, 2024 and December 31, 2023, respectively. Included within Short-term investments as of March 31, 2024 and December 31, 2023, were £55 million ($70 million at March 31, 2024 exchange rates) and £63 million ($80 million at December 31, 2023 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 March 31,
	2024		2023
Foreign currency remeasurement	4		(19)
Equity earnings	2		3
Pension and other postretirement	(10)		(17)
Financial instruments and other (1)	79		8
Total	$	75	$	(25)

(1)For the period ended March 31, 2024, an $82 million gain was recognized 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 March 31,
	2024		2023
Balance at beginning of period	$	79	$	76
Provision	5		7
Accounts written off, net of recoveries	(2)		—
Foreign currency translation and other	(1)		—
Balance at end of period	$	81	$	83

Other Current Assets

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

As of	March 31, 2024		December 31, 2023
Assets held for sale (1)	$	446	$	354
Costs to fulfill contracts with customers (2)	269		370
Prepaid expenses	128		100
Taxes receivable	19		35
Other	158		137
Total	$	1,020	$	996

(1)Refer to Note 7 “Acquisitions and Dispositions of Businesses” for further information.

(2)Refer to Note 3 “Revenue from Contracts with Customers” for further information.

Other Non-Current Assets

The components of Other non-current assets are as follows (in millions):

As of	March 31, 2024		December 31, 2023
Costs to obtain contracts with customers (1)	$	194	$	195
Taxes receivable	98		100
Investments	80		45
Leases	21		26
Other	132		140
Total	$	525	$	506

(1)Refer to Note 3 “Revenue from Contracts with Customers” for further information.

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Other Current Liabilities

The components of Other current liabilities are as follows (in millions):

As of	March 31, 2024		December 31, 2023
Taxes payable	$	397	$	291
Deferred revenue (1)	360		270
Leases	179		182
Liabilities held for sale (2)	129		69
Other	1,081		1,066
Total	$	2,146	$	1,878

(1)During the three months ended March 31, 2024, revenue of $179 million was recognized in the Condensed Consolidated Statements of Income. During the three months ended March 31, 2023, revenue of $167 million was recognized in the Condensed Consolidated Statements of Income.

(2)Refer to Note 7 “Acquisitions and Dispositions of Businesses” for further information.

Other Non-Current Liabilities

The components of Other non-current liabilities are as follows (in millions):

As of	March 31, 2024		December 31, 2023
Taxes payable (1)	$	866	$	827
Compensation and benefits	55		59
Deferred revenue	31		33
Leases	5		10
Other	146		145
Total	$	1,103	$	1,074

(1)Includes $72 million for the non-current portion of the one-time mandatory transition tax on accumulated foreign earnings as of March 31, 2024 and December 31, 2023.

7. Acquisitions and Dispositions of Businesses

Completed Acquisitions

The Company completed no acquisitions during the three months ended March 31, 2024 and no acquisitions during the three months ended March 31, 2023.

2023 Acquisitions

On November 30, 2023, the Company completed the acquisition of 100% of the share capital of Gi&Bi S.r.l., an Italy-based insurance broker specialized in the agricultural business segment.

On August 30, 2023, the Company completed the acquisition of 100% of the share capital of NGS (Uruguay) S.A., a risk management consultant firm in Uruguay.

On June 22, 2023, the Company completed the acquisition of 100% of the share capital of Benefits Corredores de Seguros and Asesorías e Inversiones Benefits, a business that provides health and benefits brokerage and benefit administration in Chile.

Completed Dispositions

The Company completed one disposition during the three months ended March 31, 2024 and no dispositions during the three months ended March 31, 2023.

There were no pretax gains recognized related to dispositions for the three months ended March 31, 2024 or 2023, respectively. Gains recognized as a result of a disposition are included in Other income (expense) in the Condensed Consolidated Statements of Income. There were no losses recognized for the three months ended March 31, 2024 or 2023, respectively.

Assets and Liabilities Held for Sale

As of March 31, 2024, Aon classified certain assets and liabilities as held for sale, as the Company has committed to a plan to sell the assets and liabilities within one year. Total assets and liabilities, for disposal groups classified as held for sale within

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Other current assets and Other current liabilities in the Condensed Consolidated Statements of Financial Position were $446 million and $129 million, respectively. Of the $446 million total assets classified as held for sale, $156 million relate to intangible assets.

Other Significant Activity

On May 1, 2017, the Company completed the sale of the 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 purchases 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. In the first quarter of 2024, the Company earned $82 million of deferred consideration from the Buyer and the other designated purchasers.

8. Goodwill and Other Intangible Assets

The changes in the net carrying amount of goodwill for the three months ended March 31, 2024 are as follows (in millions):

Balance as of December 31, 2023	$	8,414
Foreign currency translation and other	(112)
Balance as of March 31, 2024	$	8,302

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

	March 31, 2024						December 31, 2023
	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	$	1,857	$	1,683	$	174	$	1,873	$	1,686	$	187
Technology and other	367		324		43		371		324		47
Total	$	2,224	$	2,007	$	217	$	2,244	$	2,010	$	234

The estimated future amortization for finite-lived intangible assets as of March 31, 2024 is as follows (in millions):

Remainder of 2024	$	52
2025	55
2026	34
2027	22
2028	17
2029	12
Thereafter	25
Total	$	217

9. Debt

Notes

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 that was used, together with the proceeds of the delayed draw term loan available under the credit agreement entered into on February 16, 2024 described below, 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.

On February 16, 2024, Aon North America, Inc. entered into a credit agreement in which lenders committed to provide a $2 billion delayed draw term loan, which was subsequently drawn on April 25, 2024. The Company intends to use proceeds, together with the proceeds of the notes issued on March 1, 2024 described above, to pay a portion of the cash consideration in connection with the NFP acquisition, to repay certain debt of NFP and to pay related fees and expenses.

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In November 2023, Aon Global Limited’s $350 million 4.00% Senior Notes matured and were repaid in full.

In June 2023, Aon Global Limited’s $600 million 3.50% Senior Notes due June 2024 were classified as Short-term debt and current portion of long-term debt in the Condensed Consolidated Statement of Financial Position as the date of maturity is in less than one year.

On February 28, 2023, Aon Corporation, a Delaware corporation, and Aon Global Holdings plc, a public limited company formed under the laws of England and Wales, both wholly owned subsidiaries of the Company, co-issued $750 million 5.35% Senior Notes due in February 2033. The Company intends to use the net proceeds from the offering for general corporate purposes.

Revolving Credit Facilities

As of March 31, 2024, Aon 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 and the delayed draw term loan 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 nor the delayed draw term loan as of March 31, 2024 and December 31, 2023, respectively. Additionally, Aon was in compliance with the financial covenants and all other covenants contained therein during the rolling 12 months ended March 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 Program”). Commercial paper may be issued in aggregate principal amounts of up to approximately $1.3 billion under the U.S. Program and €625 million ($677 million at March 31, 2024 exchange rates) under the European Program, not to exceed the amount of the Company’s committed credit facilities, which was $2.0 billion at March 31, 2024. 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 Condensed Consolidated Statements of Financial Position, is as follows (in millions):

	March 31, 2024		December 31, 2023
Commercial paper outstanding	$	—	$	597

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

	Three Months Ended March 31,
	2024			2023
Weighted average commercial paper outstanding	$	381		$	393
Weighted average interest rate of commercial paper outstanding	5.65		%	3.38		%

10. Income Taxes

The effective tax rate on Net income was 23.2% for the three months ended March 31, 2024. The effective tax rate on Net income was 19.6% for the three months ended March 31, 2023.

For the three months ended March 31, 2024, the tax rate was primarily driven by the geographical distribution of income and certain discrete items, including the favorable impact of share-based payments offset by the unfavorable impact of discrete items.

For the three months ended March 31, 2023, the tax rate was primarily driven by the geographical distribution of income and certain discrete items, primarily the favorable impacts of share-based payments.

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11. Shareholders’ Equity (Deficit)

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 March 31,
	2024		2023
Shares repurchased	0.8		1.8
Average price per share	$	310.56	$	305.31
Repurchase costs recorded to accumulated deficit	$	250	$	550

At March 31, 2024, the remaining authorized amount for share repurchases under the Repurchase Program was approximately $3.1 billion. Under the Repurchase Program, the Company has repurchased a total of 169.9 million shares for an aggregate cost of approximately $24.4 billion.

Weighted Average Ordinary Shares

Weighted average ordinary shares outstanding are as follows (in millions):

	Three Months Ended March 31,
	2024	2023
Basic weighted average ordinary shares outstanding	199.1	206.1
Dilutive effect of potentially issuable shares	1.0	1.0
Diluted weighted average ordinary shares outstanding	200.1	207.1

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 0.1 million shares excluded from the calculation for the three months ended March 31, 2024 and no shares excluded from the calculation for the three months ended March 31, 2023.

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 December 31, 2023	$	2	$	(1,584)	$	(2,791)	$	(4,373)
Other comprehensive income (loss) before reclassifications, net	72		(132)		—		(60)
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income	4		—		35		39
Tax expense	(1)		—		(9)		(10)
Amounts reclassified from accumulated other comprehensive income, net	3		—		26		29
Net current period other comprehensive income (loss)	75		(132)		26		(31)
Balance at March 31, 2024	$	77	$	(1,716)	$	(2,765)	$	(4,404)

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	Change in Fair Value of Financial Instruments (1)		Foreign Currency Translation Adjustments		Postretirement Benefit Obligation (2)		Total
Balance at December 31, 2022	$	(11)	$	(1,861)	$	(2,751)	$	(4,623)
Other comprehensive income (loss) before reclassifications, net	—		54		(1)		53
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income	5		—		32		37
Tax expense	(2)		—		(9)		(11)
Amounts reclassified from accumulated other comprehensive income, net	3		—		23		26
Net current period other comprehensive income (loss)	3		54		22		79
Balance at March 31, 2023	$	(8)	$	(1,807)	$	(2,729)	$	(4,544)

(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.

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 March 31,
	U.K.				U.S.				Other
	2024		2023		2024		2023		2024		2023
Service cost	$	—	$	—	$	—	$	—	$	—	$	—
Interest cost	35		36		23		26		9		10
Expected return on plan assets, net of administration expenses	(47)		(46)		(33)		(30)		(13)		(12)
Amortization of prior-service cost	1		—		—		—		—		—
Amortization of net actuarial loss	20		18		7		9		3		3
Net periodic (benefit) cost	9		8		(3)		5		(1)		1
Loss on pension settlement	—		—		—		—		—		—
Total net periodic (benefit) cost	$	9	$	8	$	(3)	$	5	$	(1)	$	1

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, $53 million, and $13 million (at December 31, 2023 exchange rates) to its significant U.K., U.S., and other major pension plans, respectively, during 2024. The following table summarizes contributions made to the Company’s significant pension plans (in millions):

	Three Months Ended March 31,
	2024		2023
Contributions to U.K. pension plans	$	1	$	1
Contributions to U.S. pension plans	14		16
Contributions to other major pension plans	2		6
Total contributions	$	17	$	23

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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 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)
	March 31, 2024		December 31, 2023		March 31, 2024		December 31, 2023		March 31, 2024		December 31, 2023
Foreign exchange contracts
Accounted for as hedges	$	736	$	1,724	$	36	$	34	$	—	$	2
Not accounted for as hedges (3)	459		382		1		2		—		1
Total	$	1,195	$	2,106	$	37	$	36	$	—	$	3

(1)Included within Other current assets ($19 million at March 31, 2024 and $17 million at December 31, 2023) or Other non-current assets ($18 million at March 31, 2024 and $19 million at December 31, 2023).

(2)Included within Other current liabilities ($3 million at December 31, 2023).

(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 March 31,
	2024		2023
Gain recognized in Accumulated other comprehensive loss	$	97	$	—

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

	Three Months Ended March 31,
	2024		2023
Losses recognized in Total revenue	$	(4)	$	(5)

The Company estimates that approximately $2 million of pretax gains currently included within Accumulated other comprehensive loss will be reclassified into earnings in the next twelve months.

During the three months ended March 31, 2024 and March 31, 2023, the Company recorded a loss of $3 million and gain of $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 March 31, 2024 and December 31, 2023 (in millions):

			Fair Value Measurements Using
	Balance at March 31, 2024		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets
Money market funds (1)	$	8,236	$	8,236	$	—	$	—
Other investments
Government bonds	$	1	$	—	$	1	$	—
Derivatives (2)
Gross foreign exchange contracts	$	58	$	—	$	58	$	—
Liabilities
Derivatives (2)
Gross foreign exchange contracts	$	22	$	—	$	22	$	—

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			Fair Value Measurements Using
	Balance at December 31, 2023		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets
Money market funds (1)	$	3,204	$	3,204	$	—	$	—
Other investments
Government bonds	$	1	$	—	$	1	$	—
Derivatives (2)
Gross foreign exchange contracts	$	49	$	—	$	49	$	—
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 months ended March 31, 2024 or 2023. The Company recognized no realized or unrealized gains or losses in the Condensed Consolidated Statements of Income during the three months ended March 31, 2024 or 2023 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):

	March 31, 2024				December 31, 2023
	Carrying Value		Fair Value		Carrying Value		Fair Value
Current portion of long-term debt	$	600	$	598	$	600	$	595
Long-term debt	$	15,916	$	15,151	$	9,995	$	9,223

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. Finally, in April 2021, representatives of 16 passengers issued a claim against Aon in the High Court in England seeking damages under the Fatal Accidents Act 1976 in the sum of £29 million ($37 million at March 31, 2024 exchange rates). In February 2024, the claim brought by representatives of 16 passengers in the High Court in England was dismissed pursuant to an agreement among the parties. 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. 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 is one of the third parties that identifies capital providers to collateralize insurance and reinsurance obligations of the Company’s clients and counterparties. 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 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 may also seek recourse against third parties where appropriate, including in connection with bankruptcy proceedings filed by Vesttoo in the Bankruptcy Court for the U.S. District of Delaware. 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. 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 the Trustee (amending and restating the Amended and Restated Indenture, dated April 2, 2012, amending and restating the

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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).

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 $139 million at March 31, 2024, and $86 million at December 31, 2023. 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 $110 million at March 31, 2024 compared to $194 million at December 31, 2023.

16. Segment Information

The Company operates as one segment that includes all of Aon’s operations, which as a global professional services firm provides a broad range of Risk and Human Capital Solutions through four solution lines — Commercial risk, Reinsurance, Health, and Wealth, which make up its principal products and services. The CODM assesses the performance of the Company and allocates resources based on one segment: Aon United.

The Company’s reportable operating segment has been determined using a management approach, which is consistent with the basis and manner in which the CODM uses financial information for the purposes of allocating resources and evaluating performance. The CODM assesses performance and allocates resources based on total Aon results against its key four metrics, expense discipline, and collaborative behaviors that maximize value for Aon and its shareholders, regardless of which solution line it benefits.

As Aon operates as one segment, segment profit or loss is consistent with consolidated reporting as disclosed in the Condensed Consolidated Statements of Income. Refer to Note 3 “Revenue from Contracts with Customers” for further information on revenue by principal service line.

17.    Subsequent Events

NFP Acquisition

On April 25, 2024, the Company completed its acquisition of NFP, a leading middle-market provider of property and casualty brokerage, benefits consulting, wealth management, and retirement plan consulting, with more than 7,700 colleagues. The Company acquired NFP Intermediate Holdings A Corp. in a cash-and-stock merger for an aggregate preliminary purchase price totaling $9.1 billion, with approximately $3.2 billion to settle NFP indebtedness and cash consideration to the selling shareholders, and approximately 19 million class A ordinary shares with a fair value of approximately $5.9 billion. The initial accounting for the acquisition is incomplete as of the date of this Form 10-Q, as the information necessary to complete such evaluations was not practicable due to the timing of acquisition closing. We have not yet determined the purchase price allocation, including the fair value of the acquisition. The preliminary accounting impact of this acquisition will be included in our Condensed Consolidated Financial Statements beginning in the second quarter of 2024.

Debt Activity

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,

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dated as of April 2, 2024. On April 26, 2024, the Offeror 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.

Disposition of Business

On April 20, 2024, Aon signed a definitive agreement to sell Healthy Paws, its U.S.-based managing general agent specializing in pet insurance, to Chubb Limited. Assets and liabilities associated with this disposal group were classified as held for sale as of March 31, 2024. The disposition is expected to be completed in the second quarter of 2024.

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Item 2.  Management’s