Aon plcAON
Aon plc Income Taxes Disclosure
Income Taxes
Income before income tax and the provision for income tax consist of the following (in millions):
| Years Ended December 31 | |||||||||||||||||
2025 | 2024 | 2023 | |||||||||||||||
| Income before income taxes: | |||||||||||||||||
| Ireland | $ | 162 | $ | 52 | $ | 31 | |||||||||||
| U.K. | 663 | 782 | 338 | ||||||||||||||
| U.S. | 1,220 | 854 | 219 | ||||||||||||||
| Other | 2,714 | 1,774 | 2,581 | ||||||||||||||
| Total | $ | 4,759 | $ | 3,462 | $ | 3,169 | |||||||||||
| Income tax expense: | |||||||||||||||||
| Current: | |||||||||||||||||
| Ireland | $ | 12 | $ | 13 | $ | 4 | |||||||||||
| U.K. | 164 | 233 | 185 | ||||||||||||||
| U.S. federal | 422 | 292 | 240 | ||||||||||||||
| U.S. state and local | 110 | 79 | 74 | ||||||||||||||
| Other | 442 | 436 | 411 | ||||||||||||||
| Total current tax expense | $ | 1,150 | $ | 1,053 | $ | 914 | |||||||||||
| Deferred tax expense (benefit): | |||||||||||||||||
| Ireland | $ | (1) | $ | — | $ | — | |||||||||||
| U.K. | (44) | (169) | (116) | ||||||||||||||
| U.S. federal | (92) | (83) | (126) | ||||||||||||||
| U.S. state and local | 20 | (71) | (39) | ||||||||||||||
| Other | (24) | 12 | (92) | ||||||||||||||
| Total deferred tax expense (benefit) | $ | (141) | $ | (311) | $ | (373) | |||||||||||
| Total income tax expense | $ | 1,009 | $ | 742 | $ | 541 | |||||||||||
Income before income taxes shown above may, in some cases, be subject to taxation in more than one country, and as a result the income tax provision shown above as Ireland, U.K., U.S. or Other may not correspond to the geographic attribution of the earnings.
The Company performs a reconciliation of the income tax provisions based on its domicile and statutory rate at each reporting period. The reconciliation of the income tax provisions based on the Irish statutory corporate tax rate of 25% to the provisions reflected in the Consolidated Financial Statements is as follows:
| Year Ended December 31 | |||||||||||
2025 | |||||||||||
| $ | % | ||||||||||
| Provision for income taxes at the Irish statutory tax rate | $1,190 | 25.0% | |||||||||
| Foreign Tax Effects | |||||||||||
| United States | |||||||||||
| State and local income taxes, net of federal income tax effect | 83 | 1.7 | |||||||||
| Effect of cross-border tax laws | (60) | (1.3) | |||||||||
| Other | (2) | — | |||||||||
| Bermuda | |||||||||||
| Deferred tax adjustment | (143) | (3.0) | |||||||||
| Changes in valuation allowances | 114 | 2.4 | |||||||||
| Other | (1) | — | |||||||||
| Singapore | |||||||||||
| Incentive | (120) | (2.5) | |||||||||
| Statutory tax rate difference between Singapore and Ireland | (101) | (2.1) | |||||||||
| Other | (37) | (0.8) | |||||||||
| Other foreign jurisdictions | (5) | (0.1) | |||||||||
| Changes in unrecognized tax benefits | 121 | 2.5 | |||||||||
| Other adjustments | (30) | (0.6) | |||||||||
| Income tax expense and effective tax rate | $1,009 | 21.2% | |||||||||
Below is a reconciliation of the Irish statutory corporate tax rate and the Company’s effective tax rate for the years ended December 31, 2024 and 2023.
| Years Ended December 31 | |||||||||||
| 2024 | 2023 | ||||||||||
| Statutory tax rate | 25.0% | 25.0% | |||||||||
| U.S. state income taxes, net of U.S. federal benefit | 0.7 | 0.6 | |||||||||
Taxes on international operations (1) | (9.3) | (11.2) | |||||||||
| Nondeductible expenses | 1.8 | 3.2 | |||||||||
| Adjustments to prior year tax requirements | 0.8 | 0.5 | |||||||||
| Deferred tax adjustments, including statutory rate changes | (0.1) | (0.3) | |||||||||
| Deferred tax adjustments, international earnings | 1.1 | 0.7 | |||||||||
| Adjustments to valuation allowances | (0.1) | (2.5) | |||||||||
| Change in uncertain tax positions | 2.3 | 2.6 | |||||||||
Excess tax benefits related to shared based compensation (2) | (0.7) | (1.6) | |||||||||
| Capital and other losses | — | — | |||||||||
| Other — net | (0.1) | 0.1 | |||||||||
| Effective tax rate | 21.4% | 17.1% | |||||||||
(1)The Company determines the adjustment for taxes on international operations based on the difference between the statutory tax rate applicable to earnings in each foreign jurisdiction and the enacted rate of 25.0% and 25.0% at December 31, 2024, and 2023, respectively. The benefit to the Company’s effective income tax rate from taxes on international operations relates to benefits from lower-taxed global operations, primarily due to the use of global funding structures and the tax holiday in Singapore.
(2)Excess tax benefits and deficiencies from share-based payment transactions are recognized as income tax expense or benefit in the Company’s Consolidated Statements of Income.
The Company has elected to account for GILTI in the period in which it is incurred, and therefore has not provided deferred tax impacts of GILTI in its Consolidated Financial Statements.
Cash taxes paid (net of refunds) by jurisdiction:
| Year Ended December 31 | |||||
2025 | |||||
| Federal (Ireland) | $ | 11 | |||
| Foreign | |||||
| United States federal | $ | 247 | |||
| United Kingdom | $ | 240 | |||
| Canada | $ | 74 | |||
| Singapore | $ | 54 | |||
| All other foreign | $ | 410 | |||
| Cash taxes paid (net of refunds) | $ | 1,036 | |||
The Company’s total cash taxes paid, net of refunds, were $1,053 million and $740 million for the years ended December 31, 2024 and 2023, respectively.
The components of the Company’s deferred tax assets and liabilities are as follows (in millions):
| As of December 31 | 2025 | 2024 | |||||||||
| Deferred tax assets: | |||||||||||
| Net operating loss, capital loss, interest, and tax credit carryforwards | $ | 1,682 | $ | 1,576 | |||||||
| Employee benefit plans | 325 | 359 | |||||||||
| Lease liabilities | 157 | 171 | |||||||||
| Other accrued expenses | 166 | 176 | |||||||||
| Federal and state benefit of interest from uncertain tax positions | 127 | 99 | |||||||||
| Accrued interest | 16 | 102 | |||||||||
| Deferred revenue | 34 | 31 | |||||||||
Investment basis differences (1) | 5 | (42) | |||||||||
| Other | 58 | 56 | |||||||||
| Total | 2,570 | 2,528 | |||||||||
| Valuation allowance on deferred tax assets | (306) | (202) | |||||||||
| Total | $ | 2,264 | $ | 2,326 | |||||||
| Deferred tax liabilities: | |||||||||||
| Intangibles and property, plant and equipment | $ | (1,367) | $ | (1,512) | |||||||
| Deferred costs | (184) | (160) | |||||||||
| Lease right-of-use asset | (125) | (139) | |||||||||
| Unremitted earnings | (55) | (66) | |||||||||
| Other accrued expenses | (23) | (21) | |||||||||
| Unrealized foreign exchange gains | (41) | (36) | |||||||||
| Other | (61) | (57) | |||||||||
| Total | $ | (1,856) | $ | (1,991) | |||||||
| Net deferred tax asset | $ | 408 | $ | 335 | |||||||
(1)The balance was in a liability position for the comparable period.
Deferred income taxes (assets and liabilities have been netted by jurisdiction) have been classified in the Consolidated Statements of Financial Position as follows (in millions):
| As of December 31 | 2025 | 2024 | |||||||||
| Deferred tax assets — non-current | 748 | 654 | |||||||||
| Deferred tax liabilities — non-current | (340) | (319) | |||||||||
| Net deferred tax asset | 408 | 335 | |||||||||
In assessing the realizability of deferred tax assets, the Company considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized and adjusts the valuation allowance accordingly. Considerations with respect to the realizability of deferred tax assets include the period of expiration of the deferred tax asset, historical earnings and projected future taxable income by jurisdiction as well as tax liabilities for the tax jurisdiction to which the tax asset relates. Significant management judgment is required in determining the assumptions and estimates related to the amount and timing of future taxable income. Valuation allowances have been established primarily with regard to the tax benefits of certain tax credits, net operating loss carryforwards, and capital loss carryforwards. Valuation allowances increased by $104 million as of December 31, 2025, when compared to December 31, 2024. The change is primarily attributable to the establishment of a valuation allowance related to certain intangible assets, partially offset by a release of valuation allowances related to certain foreign tax credits.
The Company generally intends to limit distributions from foreign subsidiaries in excess of U.S. tax earnings and profits (except where distributions would be limited by available cash) and to limit repatriations from certain other jurisdictions that would otherwise generate a U.S. tax liability. As of December 31, 2025, the Company has accrued $55 million for local country income taxes, withholding taxes and state income taxes on those undistributed earnings that are not indefinitely reinvested. The Company has not provided for deferred taxes on outside basis differences in our investments in our foreign subsidiaries that are unrelated to these accumulated undistributed earnings, as these outside basis differences are indefinitely reinvested. A determination of the unrecognized deferred taxes related to these other components of our outside basis differences is not practicable.
The Company had the following carryforwards (in millions):
| As of December 31 | 2025 | 2024 | |||||||||
| U.K. | |||||||||||
| Operating loss carryforwards | $ | 1,587 | $ | 1,499 | |||||||
| Capital loss carryforwards | $ | 593 | $ | 557 | |||||||
| Interest carryforwards | $ | 112 | $ | 85 | |||||||
| U.S. | |||||||||||
| Federal operating loss carryforwards | $ | 1 | $ | 2 | |||||||
| Federal interest carryforwards | $ | 4,117 | $ | 3,743 | |||||||
| Federal foreign tax credit carryforwards | $ | 25 | $ | 29 | |||||||
| State operating loss carryforwards | $ | 1,348 | $ | 1,822 | |||||||
| State interest carryforwards | $ | 2,427 | $ | 2,303 | |||||||
| Other Non-U.S. | |||||||||||
| Operating loss carryforwards | $ | 453 | $ | 339 | |||||||
| Capital loss carryforwards | $ | 10 | $ | 9 | |||||||
| Interest carryforwards | $ | 176 | $ | 126 | |||||||
The U.K. operating losses and capital losses have an indefinite carryforward period. The federal operating loss carryforwards generated through December 31, 2017 expire at various dates between 2034 and 2036 while federal operating loss carryforwards generated after this date have indefinite carryforward periods. State net operating losses as of December 31, 2025 have various carryforward periods and will begin to expire in 2026. Federal and state interest carryforwards have indefinite carryforward periods. Foreign tax credits can be carried forward for ten years and will begin to expire in 2029. Operating and capital losses in other non-U.S. jurisdictions have various carryforward periods and will begin to expire in 2026. The interest carryforwards in other non-U.S. jurisdictions have an indefinite carryforward period.
During 2012, the Company was granted a tax holiday for the period from October 1, 2012 through September 30, 2022, with respect to withholding taxes and certain income derived from services in Singapore. The Company has been granted a new incentive for the period October 1, 2022 to September 30, 2032. The new incentive provides for a reduced withholding tax rate and a reduced tax rate on certain income derived from services in Singapore, as long as certain conditions are met.
The benefit realized was approximately $120 million, $96 million, and $93 million during the years ended December 31, 2025, 2024, and 2023, respectively. The impact of this tax holiday on diluted earnings per share was $0.55, $0.45, and $0.45 during the years ended December 31, 2025, 2024, and 2023, respectively.
Uncertain Tax Positions
The following is a reconciliation of the Company’s beginning and ending amount of uncertain tax positions (in millions):
| 2025 | 2024 | ||||||||||
| Balance at January 1 | $ | 722 | $ | 637 | |||||||
| Additions based on tax positions related to the current year | 52 | 39 | |||||||||
| Additions for tax positions of prior years | 14 | 1 | |||||||||
| Reductions for tax positions of prior years | (12) | (5) | |||||||||
| Settlements | — | (1) | |||||||||
| Business combinations | (1) | 61 | |||||||||
| Lapse of statute of limitations | (8) | (10) | |||||||||
| Foreign currency translation | — | — | |||||||||
| Balance at December 31 | $ | 767 | $ | 722 | |||||||
The Company’s liability for uncertain tax positions as of December 31, 2025, 2024, and 2023, includes $689 million, $643 million, and $570 million, respectively, related to amounts that would impact the effective tax rate if recognized.
The Company recognizes interest and penalties related to uncertain tax positions in its provision for income taxes. The Company accrued potential interest and penalties of $96 million, $73 million, and $62 million, in 2025, 2024, and 2023, respectively. The Company recorded a liability for interest and penalties of $421 million, $325 million, and $244 million as of December 31, 2025, 2024, and 2023, respectively.
The Company and its subsidiaries file income tax returns in their respective jurisdictions. The Company has substantially concluded all U.S. federal income tax matters for years through 2007. Material U.S. state and local income tax jurisdiction examinations have been concluded for years through 2014. The Company has concluded income tax examinations in its primary non-U.S. jurisdictions through 2007.
Historical Timeline
| Fiscal Year | Filed | |
|---|---|---|
| 2025 | Feb 13, 2026 | Showing above |
| 2024 | Feb 18, 2025 | |
| 2023 | Feb 16, 2024 | |
| 2022 | Feb 17, 2023 | |
| 2021 | Feb 18, 2022 | |
| 2020 | Feb 19, 2021 | |
| 2019 | Feb 14, 2020 | |
| 2018 | Feb 19, 2019 | |
| 2017 | Feb 20, 2018 | |
| 2016 | Feb 23, 2017 | |
| 2015 | Feb 22, 2016 | |
About Income Taxes Disclosures
The income tax disclosure reveals how much a company actually pays in taxes versus what the statutory rate would predict. Analysts focus on the effective tax rate (ETR) reconciliation, which breaks down every item driving the gap between the 21% federal rate and the company's reported ETR — including R&D credits, foreign rate differentials, and state taxes. Deferred tax assets (DTAs) and their valuation allowances signal management's confidence in future profitability: a rising allowance suggests the company doubts it can use accumulated tax benefits. Uncertain tax benefit (UTB) reserves quantify exposure to IRS challenges on aggressive positions.
Key signals to watch: sudden ETR drops without clear operational reasons, large increases in valuation allowances, growing UTB balances, and significant unremitted foreign earnings. Post-TCJA, pay attention to GILTI and BEAT provisions that affect multinational tax structures. Compare the cash taxes paid (from the cash flow statement) against the income tax provision to gauge earnings quality.