Aon plc (AON)
Aon provides insurance and reinsurance brokerage plus risk, retirement, and health consulting.
- Fiscal year end in SEC snapshot
- December 31
- Annual report period end
- 2025-12-31
The SEC classifies these issuers under “Insurance Agents, Brokers & Service” (SIC 6411). A shared code is a starting point for finding comparable businesses. Product mix, geography and customers can still differ substantially. Read the company descriptions before treating the group as direct competitors.
Align the reporting periods before comparing annual results. Companies with different year ends report different 12-month windows.
| Fiscal year end (SEC) | Companies |
|---|---|
| December 31 | AJG, AON, MRSH, WTW |
| January 19 | BRO |
Aon provides insurance and reinsurance brokerage plus risk, retirement, and health consulting.
Arthur J. Gallagher is an insurance brokerage and risk-management consulting firm serving businesses worldwide.
Brown & Brown is an insurance brokerage placing coverage for businesses and individuals.
Marsh & McLennan provides insurance brokerage, risk advisory, and human-capital consulting.
Willis Towers Watson provides insurance brokerage, risk advisory, and human-capital consulting.
Compare Arthur J. Gallagher & Co. and Aon plc: business context, fiscal calendars and official filings.
Compare Arthur J. Gallagher & Co. and Brown & Brown, Inc.: business context, fiscal calendars and official filings.
Compare Arthur J. Gallagher & Co. and Marsh & McLennan Companies, Inc.: business context, fiscal calendars and official filings.
Compare Arthur J. Gallagher & Co. and Willis Towers Watson Public Limited Company: business context, fiscal calendars and official filings.
Compare Aon plc and Brown & Brown, Inc.: business context, fiscal calendars and official filings.
Compare Aon plc and Marsh & McLennan Companies, Inc.: business context, fiscal calendars and official filings.
Compare Aon plc and Willis Towers Watson Public Limited Company: business context, fiscal calendars and official filings.
Compare Brown & Brown, Inc. and Marsh & McLennan Companies, Inc.: business context, fiscal calendars and official filings.
Industry codes and annual filing references come from the SEC submissions snapshot linked to each issuer in our company catalog (snapshot ; newer filings may exist). Only groups with at least three distinct issuers, business descriptions and annual filing links are included. Multiple share classes of one issuer count as one company. This is a coverage directory, not a complete industry census or a ranking of investments.
SEC Standard Industrial Classification code list explains the classification system. Read our research methodology or browse all industry directories.
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