AONAon plc

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 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 (collectively, “Clear Blue”) filed a lawsuit in New York State Supreme Court against Aon plc and Aon Insurance Managers (Bermuda) Ltd. alleging such claims. While Clear Blue and Aon has settled and/or jointly filed a stipulation of dismissal with prejudice on September 26, 2025. On August 8, 2025, the liquidating trust formed to pursue claims on behalf of the Vesttoo bankruptcy estate filed a complaint in the U.S. Bankruptcy Court of Delaware against the Company and certain of its subsidiaries, among other parties. The trust’s complaint alleges, among other theories of liability, that Aon is in discussions to settle certain claims, liable for having induced parties into taking on collateral protection insurance risks, notwithstanding the fact that fraudulent letters of credit had been arranged by Vesttoo employees and co-conspirators. Aon believes that it has meritorious defenses and intends to vigorously defend itself against those claims that are not settled. such claims, and on November 17, 2025, Aon filed a motion to dismiss the matter. 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. In the third quarter of 2025, certain legal settlement expenses and recoveries were recognized resulting in a $23 million reduction of this amount. 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.

In many jurisdictions, including in the E.U. and the U.S., we are subject to laws and regulations relating to the collection, use, retention, security, and transfer of this the confidential information of third parties, including our clients’ and employees’ confidential information. These laws and regulations are frequently changing and are becoming increasingly complex and sometimes conflict among the various jurisdictions and countries in which we provide services both in terms of substance and in terms of enforceability. This makes compliance challenging and expensive. In addition, many privacy laws and related rules and regulations require us to provide individuals with information on how their personal data is used within Aon or collected from our websites. Additionally, certain jurisdictions’ regulations include notice provisions that may require us to inform affected clients or employees, or the applicable regulatory authority, in the event of a breach of confidential information before we fully understand or appreciate the extent of the breach. These disclosure and notice provisions present operational challenges and related risk. In particular, there have been a number of recently adopted privacy laws around the globe including in China and Brazil, and but not limited to significant privacy rulings in the E.U. relating to the “Schrems II” case, E.U., which have imposed significant changes to the way companies export personal data from the E.U. We have had to implement new requirements set out in these laws within our business before the effective date, requiring significant time and resources. This new data. New guidance issued to firms by the European Regulators regulators has and will continue to require significant time and resources to implement and may require significant effort to review and effect applicable changes to IT systems and transfer methods. Non-compliance with new and existing laws could result in proceedings against us by governmental entities or others and additional costs in connection therewith. We expect additional jurisdictions to continue to adopt new privacy regulations and that existing regulations may be amended as governments continue to legislate in respect of personal data. We have incurred expenses and devoted resources, and will continue to incur expenses and devote resources, to bring our practices into compliance with these regulations and future regulations. Our failure to comply with or successfully implement processes in response to changing regulatory requirements in this area could result in legal liability, result in proceedings or fines against us by governmental entities or others, or impair our reputation in the marketplace. Further, regulatory initiatives in the area of data privacy and data

In November 2023, 2024, the FASB issued new accounting guidance, requiring new segment disclosures guidance under ASC 280, Segment Reporting, 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 significant segment expense categories and amounts that are regularly reported to the CODM and included in the segment’s profit or loss in interim and total selling expenses and, on an annual periods. basis, an entity’s definition of selling expenses. The new guidance is effective for the year ended December 31, 2024 and interim periods thereafter. The Company has adopted 2027, with early adoption permitted. Entities may apply the new guidance effective December 31, 2024, on a prospective basis, with the option for retrospective basis for all periods presented and prior period comparative segment information has been recast application. The company is currently evaluating the impact the guidance will have on the Notes to conform with current year presentation within Note 17 “Segment Information”. Consolidated Financial Statements.

(4)On April 25, 2024, the Company completed the acquisition of NFP. As part of the acquisition, Aon incurred $191 million transaction and integration costs in 2024. Transaction (4)Transaction costs include advisory, legal, accounting, regulatory, and other professional or consulting fees required to complete the acquisition. $96 million in NFP Transaction. No transaction costs were recognized in 2024. In for the twelve months ended December 31, 2025. For the twelve months ended December 31, 2024, $90 million of transaction costs were recognized in Total operating expenses and $6 million were recognized in Other income (expense) related to the extinguishment of acquired NFP debt. The NFP Transaction will also 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 management processes and controls, as well as costs associated with the assessment of NFP information technology environment and security protocols. Aon incurred $95 million of integration costs in 2024.