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Compare · AON vs MMC

AON vs MMC

Side-by-side comparison of Aon plc (AON) and Marsh & McLennan Companies Inc. (MMC): market cap, price performance, sector, and recent activity on the wire.

Summary

  • Both AON and MMC operate in Specialty Insurers (Finance), so they compete in similar markets.
  • MMC is the larger of the two at $75.87B, about 1.1x AON ($70.17B).
  • Over the past year, AON is down 7.2% and MMC is down 18.0% - AON leads by 10.8 points.
  • AON has hit the wire 4 times in the past 4 weeks while MMC has been quiet.
  • Both have 25 recent analyst ratings on file.
PerformanceAON+0.74%MMC-17.98%
2025-10-29+0.00%2026-06-05
MetricAONMMC
Company
Aon plc
Marsh & McLennan Companies Inc.
Price
$328.64+1.98%
$182.52-1.65%
Market cap
$70.17B
$75.87B
1M return
+6.62%
-0.51%
1Y return
-7.16%
-17.98%
Industry
Specialty Insurers
Specialty Insurers
Exchange
NYSE
NYSE
IPO
News (4w)
4
0
Recent ratings
25
25
AON

Aon plc

Aon plc, a professional services firm, provides advice and solutions to clients focused on risk, retirement, and health worldwide. It offers commercial risk solutions, including retail brokerage, cyber, and global risk consulting solutions, as well as acts as a captive insurance solutions provider; and health solutions, such as health and benefits brokerages, and health care exchanges. The company also provides treaty and facultative reinsurance, as well as insurance-linked securities, capital raising, strategic advice, restructuring, and mergers and acquisitions services; and corporate finance advisory services and capital markets solutions products. In addition, it offers strategic design consulting services on their retirement programs, actuarial services, and risk management services; advice services on developing and maintaining investment programs across a range of plan types, including defined benefit plans, defined contribution plans, endowments, and foundations for public and private companies, and other institutions; and advice and solutions that help clients in accelerating business outcomes by enhancing the performance of their people, including assessment and optimized deployment, as well as the design, alignment, and benchmarking of compensation to business strategy and performance outcomes. Further, the company develops, markets, and administers customized insurance programs and specialty market solutions for organizations, and their members or affiliates; operates the Global Risk Insight Platform, which provides data, analytics, engagement, and consulting services; offers CoverWallet, a digital insurance platform for small- and medium-sized businesses; and provides ReView that provides advisory, analysis, and benchmarking services to help reinsurers. Aon plc was founded in 1919 and is headquartered in Dublin, Ireland.

MMC

Marsh & McLennan Companies Inc.

Marsh & McLennan Companies, Inc., a professional services company, provides advice and solutions to clients in the areas of risk, strategy, and people worldwide. It operates in two segments, Risk and Insurance Services, and Consulting. The Risk and Insurance Services segment offers risk management services, such as risk advice, risk transfer, and risk control and mitigation solutions, as well as insurance and reinsurance broking, catastrophe and financial modeling, and related advisory services; and insurance program management services. This segment serves businesses, public entities, insurance companies, associations, professional services organizations, and private clients. The Consulting segment provides health, wealth, and career consulting services and products; and specialized management, as well as economic and brand consulting services. Marsh & McLennan Companies, Inc. has collaboration with Chubb Limited to secure insurance coverage for the COVAX no-fault compensation program. The company was founded in 1871 and is headquartered in New York, New York.

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