Ticker League

Current

$80.9B

As of Jul 29, 2026

5-Year Average

$69.2B

All-Time High

$89.4B

Mar 3, 2025

All-Time Low

$4.6B

Nov 1, 2002

Market cap daily chart for Aon (AON)

Aug 2, 2021 – Jul 29, 2026 · 1,253 trading days

Market Cap growth chart for Aon (AON) from 2017 to 2026

Latest: +5.9%

Market Cap history table for Aon (AON) from 1985 to 2026

  • 2026$80.9B+5.9%
  • 2025$76.4B+0.1%
  • 2024$76.3B+27.9%
  • 2023$59.7B-6.8%
  • 2022$64B-5.8%
  • 2021$68B+38.0%
  • 2020$49.2B-1.7%
  • 2019$50.1B+39.6%
  • 2018$35.9B+2.8%
  • 2017$34.9B+15.9%
  • 2016$30.1B+15.2%
  • 2015$26.2B-7.9%
  • 2014$28.4B+7.4%
  • 2013$26.5B+43.1%
  • 2012$18.5B+15.9%
  • 2011$16B+16.3%
  • 2010$13.7B+22.9%
  • 2009$11.2B-18.8%
  • 2008$13.7B-10.8%
  • 2007$15.4B+27.4%
  • 2006$12.1B-1.5%
  • 2005$12.3B+52.9%
  • 2004$8.03B+5.6%
  • 2003$7.61B+40.1%
  • 2002$5.43B-43.7%
  • 2001$9.65B+6.4%
  • 2000$9.07B-13.7%
  • 1999$10.5B+9.7%
  • 1998$9.58B-4.3%
  • 1997$10B+43.1%
  • 1996$6.99B+28.9%
  • 1995$5.42B+59.6%
  • 1994$3.4B-0.8%
  • 1993$3.43B-12.0%
  • 1992$3.9B+50.8%
  • 1991$2.58B+12.3%
  • 1990$2.3B-17.0%
  • 1989$2.77B+54.4%
  • 1988$1.79B+18.8%
  • 1987$1.51B-13.5%
  • 1986$1.75B+0.9%
  • 1985$1.73B

Market Cap values are taken from Aon's reported income statements (share counts) and end-of-day prices (interim 6-K and annual 20-F filings with the U.S. Securities and Exchange Commission). Each row shows the period end date and the filing date. YoY compares each figure to the same period one year earlier. Amounts are in USD as filed.

About Market Cap at Aon (AON)

According to Aon's latest reported financial statements, the company's latest reported market cap is $71.2B. Market capitalization is the total dollar value of all outstanding shares — shares outstanding × stock price — and the standard measure of a company's equity value. On this page, historical market cap snaps filing-period share counts to closing prices on or before each statement date (not intraday tick data).

Headline figure above is from the reporting period ending (reported ). Chart and table below cover the full reported history back to .

As of the 2026 fiscal year, Aon (AON) reported market cap of $80.9B – grew 5.9% year-over-year.

Aon market cap compound annual growth for the 2021–2026 (5 years) window is +3.6%, sustaining 3 straight years of year-over-year growth.

Across the available history, market cap reached its high of $80.9B in 2026 and its low of $1.51B in 1987.

Aon Market Cap by Year

Aon Market Cap 2026: $80.9B

2026's market cap for Aon came in at $80.9B, grew 5.9% from 2025. This figure represents the highest annual value in the available history.

Aon Market Cap 2025: $76.4B

Aon posted market cap of $76.4B in 2025, edged up 0.1% from 2024.

Aon Market Cap 2024: $76.3B

In 2024, Aon reported market cap of $76.3B, grew 27.9% from 2023.

Aon Market Cap 2023: $59.7B

Aon market cap in 2023 was $59.7B, declined 6.8% below 2022.

Aon Market Cap 2022: $64B

Aon market cap in 2022 was $64B.

See more financial history for Aon (AON).

Sector peers by Market Cap

Financial Services peers of Aon (AON), ranked by their latest market cap

Frequently asked questions

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