Insurance: Fair value: Level 3 measurements

The Company's financial assets and liabilities carried at fair value have been classified based upon a hierarchy defined by GAAP. The hierarchy gives the highest ranking to fair values determined using unadjusted quoted prices in active markets for identical assets and liabilities (Level 1) and the lowest ranking to fair values determined using methodologies and models with unobservable inputs (Level 3). An asset's or a liability's classification is based on the lowest level of input that is significant to its measurement. For example, a financial asset or liability carried at fair value would be classified in Level 3 if unobservable inputs were significant to the instrument's fair value, even though the measurement may be derived using inputs that are both observable (Levels 1 and 2) and unobservable (Level 3).

The Company estimates fair values using prices from third parties or internal pricing methods. Fair value estimates received from third-party pricing services are based on reported trade activity and quoted market prices when available and other market information that a market participant would use to estimate fair value. The internal pricing methods are performed by the Company's investment professionals and generally involve using discounted cash flow analyses, incorporating current market inputs for similar financial instruments with comparable terms and credit quality as well as other qualitative factors. In instances where there is little or no market activity for the same or similar instruments, fair value is estimated using methods, models and assumptions that the Company believes a hypothetical market participant would use to determine a current transaction price. These valuation techniques involve some level of estimation and judgment that becomes significant with increasingly complex instruments or pricing models.

The estimated fair values of our investments are based on unadjusted quoted prices for identical investments in active markets that are readily and regularly obtainable. When such unadjusted quoted prices are not available, estimated fair values are based on quoted prices in markets that are not active, quoted prices for similar but not identical investments, or other observable inputs. If these inputs are not available, or observable inputs are not determinable, unobservable inputs and/or adjustments to observable inputs requiring significant management judgment, including assumptions or estimates, are used to determine the estimated fair value of investments. Unobservable inputs are based on management’s assumptions about the inputs market participants would use in pricing such investments. The methodologies, assumptions and inputs utilized are described in Note 13 of the Notes to the Consolidated Financial Statements.

For most of our investments, sensitivity analysis regarding unobservable inputs is not necessary or appropriate, as they are valued using quoted prices, as described above. Quantitative information about the significant unobservable inputs used in fair value measurement and the sensitivity of the estimated fair value to changes in those inputs for the more significant asset and liability classes measured at estimated fair value on a recurring basis is presented in Note 13 of the Notes to the Consolidated Financial Statements.

Financial markets are susceptible to severe events evidenced by rapid depreciation in asset values accompanied by a reduction in asset liquidity. Our ability to sell investments, or the price ultimately realized for investments, depends upon the demand and liquidity in the market and increases the use of judgment in determining the estimated fair value of certain investments.

Investment Allowance for Credit Loss and Impairments

The significant estimates and inherent uncertainties related to our evaluation of credit loss and impairments on our investment portfolio are summarized below. See “Quantitative and Qualitative Disclosures About Market Risk” for information regarding the sensitivity of our fixed maturity securities and mortgage loan portfolios to changes in interest rates and foreign currency exchange rates.

Fixed Maturity Securities

Contingent consideration may be paid to the former owners of the business and typically will involve the acquired entity reaching specific financial results over a designated period. Contingent consideration payables are recorded at fair value and are included in the purchase price consideration at the time of the acquisition. Subsequent changes in the fair value of contingent consideration obligations are recorded in the Consolidated Statements of Income. The fair value of contingent consideration payables is based on the expected future payments to be made to the sellers of the acquired businesses in accordance with the provisions outlined in the respective purchase agreements. In determining fair value of the contingent consideration, the acquired business’s future performance is estimated using financial projections for the acquired business and measured against performance targets specified in each purchase agreement. Contingent consideration liabilities are classified as Level 3 in the fair value hierarchy due to the Company’s reliance on unobservable inputs.

Principles of Consolidation

The accompanying Consolidated Financial Statements include the accounts of Aon plc and those entities in which the Company has a controlling financial interest. To determine if Aon holds a controlling financial interest in an entity, the Company first evaluates if it is required to apply the variable interest model to the entity, otherwise, the entity is evaluated under the voting interest model. When Aon holds rights that give it the power to direct the activities of a VIE that most significantly impact the

VIE’s economic performance, combined with a variable interest that gives the right to receive potentially significant benefits or the obligation to absorb potentially significant losses, the Company has a controlling financial interest in that VIE. If the Company is the primary beneficiary of a VIE, the Company consolidates the entity and reflects any relevant noncontrolling interest of other beneficiaries of that entity on the Statement of Consolidated Financial Position. Total assets related to consolidated VIEs are less than 1 % of the Company’s Total assets on the Consolidated Statements of Financial Position as of December 31, 2025.

Aon holds a controlling financial interest in entities that are not VIEs when it, directly or indirectly holds more than 50% of the voting rights and the noncontrolling interest holders do not hold substantive participating rights.

Redeemable Noncontrolling Interests