The Filing Desk

Aon

AON · NYSE · Financials · Financials, fiscal 2016 to 2025

AON · Last close · October 26, 2026
$302.06
Value Aon yourself

Aon's revenue rose 9.4% to $17.2 billion in fiscal 2025. Its operating margin was 25.3%, up from 24.4% a year earlier. Free cash flow was $3.2 billion, up 14.2%. It paid out $1.6 billion in dividends and buybacks, 51% of free cash flow. The diluted share count rose 2.2%.

Aon plc Latest fiscal year ended December 31, 2025 10-K filed February 13, 2026 · 0001628280-26-008116 Updated
Revenue
$17.2B
9.4%
Operating margin
25.3%
0.9 pts
Net income
$3.7B
39.2%
Free cash flow
$3.2B
14.2%
Return on capital
15.6%
3.6 pts
Market cap
$64.6B
Oct 26 close
P/E
16.7x
On $18.13 EPS, 4 qtrs

Operating margin is operating income as a share of revenue. Free cash flow is cash from operations minus capital spending. Return on capital is after-tax operating income as a share of the money invested in the business: debt plus equity, minus cash. Market cap is the last closing share price times the latest diluted share count, so it is approximate. P/E is the last close divided by diluted earnings per share over the last four quarters, or the latest fiscal year where the quarters aren't available; there is none when the company made a loss.

What Aon does

Aon is a professional services firm that helps companies manage risk and workforce costs. Its main business is insurance and reinsurance brokerage: it advises clients on what coverage to buy and places it with insurers. It also sells consulting on health benefits, pensions, retirement plans and investments. It serves clients in more than 120 countries.

Aon has two segments. Risk Capital covers commercial insurance brokerage, reinsurance and related advice, and Human Capital covers health, benefits, talent and retirement services. In 2025 total revenue was $17,181 million, including $11,290 million from Risk Capital and $5,907 million from Human Capital before certain eliminations between its own units.

It earns money mainly from commissions, fees from clients, and fees from insurers for services it provides to them. Aon names Marsh McLennan, Willis Towers Watson, Arthur J Gallagher and Lockton among its competitors. At the end of 2025 it had about 60,000 employees. Its largest single client was about 1% of revenue.

Its biggest risks, as it describes them

  • Commission income that rises and falls with insurance and reinsurance market cycles it does not control.
  • Competition from other brokers, consultants, and insurers that sell directly to clients.
  • Claims from clients over errors and omissions in its advice and services.
  • Handling large amounts of client money held in transit between clients and insurers.
  • Failing to gain the expected benefits from its restructuring plan and other operating changes.
From Aon's annual report on Form 10-K, filed February 13, 2026, in our words; the 10-K has the full description and every risk factor. Updated with each new 10-K.

Charts show fiscal years, from the 10-K filings.

Revenue and margins

Revenue
US$ billions, fiscal years
Margins
Percent of revenue
GrossOperatingNetFree cash flow

Net income and earnings per share

From fiscal 2016 to 2025, earnings per share grew 14.2% a year and net income 11.1% a year, as buybacks cut the share count by 20%.

Net income
US$ billions, fiscal years; loss years in red.
Diluted earnings per share
US$ per share, fiscal years, restated for any stock splits; loss years in red.

Returns on capital

Return on capital and on equity
Percent. Return on capital is after-tax operating income over the money invested in the business (debt plus equity, minus cash); return on equity is net income over shareholders' equity. Both use the average of opening and closing balances.
Return on capitalReturn on equity

Cash flow

Free cash flow
US$ billions. Cash from operations minus capital expenditure; negative years in red.

Payouts and share count

Dividends and buybacks
US$ billions, cash paid in each fiscal year
DividendsShare buybacks
Diluted share count
Weighted-average diluted shares, millions

Valuation

Two ways to value Aon yourself, both starting from its filings: a discounted cash flow model and the price-to-earnings method.

Discounted cash flow (DCF)

A discounted cash flow (DCF) model values a business as the cash it may generate in future, discounted back to today. The starting figures come from Aon's 10-K (or, for net cash and shares, its latest 10-Q) and the assumptions are yours: start from one of three example scenarios, then change any figure to see what it implies for a share, and how that compares with the last share price.

Value per share on three example scenarios, from Aon's fiscal 2025 free cash flow of $3.2B, net cash of −$12.5B at December 31, 2025 and 217 million diluted shares, from its filings. The scenarios are fitted to Aon: the base scenario's growth in years 1 to 5 is its revenue growth over the last 3 years, 11.2% a year; the cautious and optimistic ones are lower and higher, and growth in years 6 to 10 is halfway to the long-run rate. The base scenario's discount rate is 7% for a stable business (Insurance Brokers); the cautious and optimistic ones use a point more and a point less. Select one to load it into the calculator. These are the model's arithmetic on those assumptions, not a forecast or a price target.

From the filings
Cash from operations minus capital spending in fiscal 2025.
Cash and short-term investments minus debt and finance leases at December 31, 2025. Negative means net debt.
Weighted-average diluted shares in fiscal 2025.
Your assumptions
Start from
Fitted to Aon's own revenue growth, as above. Cautious: growth of 5.5% then 4% a year, 2% after year 10, a 8% discount rate. Base: growth of 11% then 7% a year, 2.5% after year 10, a 7% discount rate. Optimistic: growth of 17% then 10% a year, 3% after year 10, a 6% discount rate.
Long-run growth forever after year 10. Usually close to inflation, and always below the discount rate.
The yearly return an investor wants for the risk. A higher rate gives a lower value.
Value per share on these assumptions
—
—
Last close, October 26, 2026
$302.06
Value on these assumptions, against the last close
—

Cash flows in years 1 to 10, valued today
—
Everything after year 10, valued today
—
Plus net cash
—
Share of value from after year 10
—
Projected free cash flow
US$ billions. Each column is one year's projected free cash flow, split into what it is worth today and the part removed by discounting.
Value todayRemoved by discounting

How the value changes with two assumptions

Value per share in US$, with the growth rates above. The highlighted cell matches the current assumptions.
How the model works. Free cash flow grows at the first rate for five years and the second rate for five more, and each year is discounted at the discount rate. Everything after year 10 is valued as year-10 cash flow × (1 + growth after year 10) ÷ (discount rate − growth after year 10), discounted back ten years. Net cash is added and the total is divided by diluted shares. The result depends entirely on the assumptions. It is not a forecast, a price target or a recommendation. The last close is the consolidated US closing price, from Databento.

Price-to-earnings (P/E) method

Another common way to value a company is to multiply its earnings per share by a price-to-earnings (P/E) multiple: the number of years of today's earnings an investor pays for a share. A higher multiple usually means investors expect earnings to grow. Choose a multiple, for example from similar companies, to see the value it gives.

Value per share on three example scenarios, from Aon's earnings per share of $18.13 (over the last four quarters). Each grows earnings for a year at the cash flow scenarios' rates and applies a multiple to next year's earnings: 16.7×, the middle of Aon's own P/E today, its peers' median and its sector's median (Aon's own P/E today) for the base scenario, 20% less and more for the cautious and optimistic ones. The price is brought back a year at 8%, 7% and 6%. Select one to load it into the calculator. These are the model's arithmetic on those assumptions, not a forecast or a price target.

Diluted earnings per share over the four quarters to June 30, 2026, from the 10-Qs and 10-K.
P/E today is the last close divided by the latest earnings per share, the four quarters' where available. Peers: Arthur J. Gallagher, Marsh McLennan, Willis Towers Watson, Brown & Brown.
Starts at Aon's revenue growth over the last 3 years, 11.2% a year, as the base scenario does.
Earnings per share in the years ahead, US$
Type your own estimate for any year; the years after it carry on at the growth rate.
Apply the multiple to earnings
A multiple on a future year's earnings gives the price then, brought back to today at the discount rate below.
The yearly return an investor wants for the risk, as in the cash flow model.
Value per share today at this multiple
—
—
Last close, October 26, 2026
$302.06
Value at this multiple, against the last close
—
Aon's P/E at the last close
16.7×
CompanyLast closeEarnings per shareP/E today
Arthur J. GallagherAJG$266.79$6.0344.2×
Marsh McLennanMRSH$194.72$8.3623.3×
Brown & BrownBRO$71.08$3.1622.5×
Willis Towers WatsonWTW$324.67$16.1620.1×
AonAON$302.06$18.1316.7×
How the P/E method works. Value per share is earnings per share times the multiple. On a future year's earnings, that gives the price in that year, which is brought back to today at the discount rate: price ÷ (1 + discount rate) for each year ahead. It is quick and easy to compare across companies, but it ignores debt and cash, and earnings can swing with one-off gains and charges, so a multiple says most about steady, profitable businesses. Like the cash flow model, the result depends entirely on the assumptions you choose. It is not a forecast, a price target or a recommendation.

Balance sheet

Fiscal year endFY21FY22FY23FY24FY25
Cash and short-term investments8361,1421,1471,3042,798
Debt incl. finance leases9,45710,82111,23217,03115,249
Net debt (negative means net cash)8,6219,67910,08515,72712,451
Net debt to EBITDA3.8x2.5x2.5x3.9x2.8x
Debt to equity———2.8x1.6x
Interest coverage6.5x9.0x7.8x4.9x5.3x
Current ratio1.0x1.0x1.0x1.0x1.1x
Quick ratio1.0x1.0x1.0x1.0x1.1x
US$ millions unless stated, at each fiscal year end. Net debt to EBITDA is debt minus cash, divided by operating income before depreciation and amortization: roughly how many years of those earnings the net debt equals. Debt to equity is debt as a multiple of shareholders' equity. Interest coverage is operating income divided by interest expense. The current ratio is current assets over current liabilities; the quick ratio leaves out inventory.

Insider trades

Over the 12 months between October 27, 2025 and October 26, 2026, 1 insider bought $7.8 million of Aon shares on the open market, and 1 insider sold $7.8 million, $3.3 million of it under trading plans set up in advance.

DateInsiderTradeSharesPriceValueFiling
Sep 2, 2026Lester B KnightDirectorBought20,000$327.48$6.5 millionForm 4
Jul 28, 2026Darren ZeidelGeneral CounselSold plan1,900$377.76$717,750Form 4
Jul 17, 2026Darren ZeidelGeneral CounselSold plan1,950$372.05$725,500Form 4
Jul 7, 2026Darren ZeidelGeneral CounselSold plan600$360.00$216,000Form 4
Feb 26, 2026Darren ZeidelGeneral CounselSold4,300$329.72$1.4 millionForm 4
Feb 17, 2026Darren ZeidelGeneral CounselSold plan5,040$325.79$1.6 millionForm 4
Feb 10, 2026Lester B KnightDirectorBought4,000$319.24$1.3 millionForm 4
Nov 5, 2025Darren ZeidelGeneral CounselSold8,800$344.52$3.0 millionForm 4
Open-market purchases and sales by officers, directors and 10% owners, from their Form 4 filings with the SEC: one row per person, day and filing, at the day's average price. Grants, option exercises and shares withheld for tax aren't counted. Insiders buy and sell for many reasons, such as taxes, spreading their savings or a plan set up months earlier, so a trade on its own says little about where a company is heading. For information only, not investment advice. Insider trades at all companies

Piotroski F-score

The F-score counts how many of nine simple tests of profitability, funding and efficiency a company passed in a year (Piotroski, 2000). The more tests passed, the stronger the year: 8 or 9 is strong, 0 to 2 weak. Companies that report no gross profit are scored on the other eight.

TestFY23FY24FY25
Net income is positivePassPassPass
Cash from operations is positivePassPassPass
Return on assets roseFailFailFail
Cash from operations exceeds net incomePassPassFail
Debt fell relative to assetsFailFailPass
Current ratio roseFailPassPass
Share count didn't risePassFailFail
Gross margin rose———
Revenue rose relative to assetsPassPassFail
F-score5 of 85 of 84 of 8
Accruals ratio−2.6%−0.9%0.4%
The accruals ratio is net income minus cash from operations, over average total assets.

Compare

Put Aon side by side with any other company we cover: revenue, growth, margins, cash flow and returns, with ten years of charts.

Similar companies

CompanyYearRevenue growthOperating marginFree cash flow marginReturn on capitalNet debt to EBITDAF-scoreCompare
AonFY259.4%25.3%18.7%15.6%2.8x4
Arthur J. GallagherFY2520.7%—12.8%9.9%3.3x3Compare
Marsh McLennanFY2510.3%23.1%18.5%15.0%2.6x5Compare
Willis Towers WatsonFY25−2.2%23.0%15.9%12.8%2.5x7Compare
Brown & BrownFY2522.8%—23.4%9.1%3.8x4Compare
Each company's latest fiscal year. Fiscal years end in different months, so the periods don't line up exactly. Free cash flow margin is free cash flow as a share of revenue. Net debt to EBITDA is explained under the balance sheet, and the F-score above.

10 years of figures

Fiscal yearFY16FY17FY18FY19FY20FY21FY22FY23FY24FY25
Income statement
Revenue9,4099,99810,77011,01311,06612,19312,47913,37615,69817,181
Revenue growth−0.8%6.3%7.7%2.3%0.5%10.2%2.4%7.2%17.4%9.4%
Gross profit——————————
Research and development——————————
Operating income1,8111,0651,5442,1692,7812,0903,6693,7853,8354,344
Net income1,4301,2631,1741,5321,9691,2552,5892,5642,6543,695
Diluted EPS (US$)5.164.704.596.378.455.5512.1412.5112.4917.02
Diluted shares (millions)270261247241233226213205212217
Cash flow
Cash from operations2,3267341,6861,8352,7832,1823,2193,4353,0353,481
Capital expenditure156183240225141137196252218263
Free cash flow2,1705511,4461,6102,6422,0453,0233,1832,8173,218
Dividends paid345364382410412447463489562629
Share buybacks1,2572,3991,4701,9601,7633,5433,2032,7001,0001,000
Acquisitions8791,029583936814162353,506394
Stock-based compensation306319338317312449397438474432
Balance sheet at fiscal year end
Cash and short-term investments7161,2858289281,1928361,1421,1471,3042,798
Debt incl. finance leases6,2055,9666,2447,4397,8249,45710,82111,23217,03115,249
Total assets26,61526,08826,42229,40532,11431,91732,70433,95948,96550,784
Total liabilities21,08321,44022,20325,95628,53130,75933,13334,70142,53541,236
Shareholders' equity5,4754,5834,1513,3753,4951,061−529−8266,1219,352
Margins and ratios
Gross margin——————————
Operating margin19.2%10.7%14.3%19.7%25.1%17.1%29.4%28.3%24.4%25.3%
Net margin15.2%12.6%10.9%13.9%17.8%10.3%20.8%19.2%16.9%21.5%
Free cash flow margin23.1%5.5%13.4%14.6%23.9%16.8%24.2%23.8%17.9%18.7%
Return on capital15.1%6.6%14.4%18.6%22.6%14.2%32.3%33.8%19.2%15.6%
Return on equity24.9%25.1%26.9%40.7%57.3%55.1%——100.2%47.8%
Return on assets5.3%4.8%4.5%5.5%6.4%3.9%8.0%7.7%6.4%7.4%
Net debt to EBITDA2.8x3.7x3.1x2.8x2.2x3.8x2.5x2.5x3.9x2.8x
US$ millions unless stated. Where a later 10-K restated a year, the latest filed figure is shown. Download all figures (CSV, US$ millions)
Source: Aon's Form 10-K filings, from SEC EDGAR. For information only, not investment advice. The Filing Desk is not affiliated with Aon.