Aon plc
Aon plc operates as a professional services firm in the United States, rest of the Americas, the United Kingdom, Ireland, rest of Europe, the Middle East, Africa, and the Asia Pacific. It operates through Risk Capital and Human Capital segments. The company offers commercial risk solutions comprising retail and insurance brokerage, specialty solutions, global risk consulting, captives management, and affinity programs; health solutions, such as consulting and brokerage, consumer benefits, and talent advisory services; and wealth solutions, including retirement consulting and investments. It also provides treaty and facultative reinsurance; strategy and technology group solutions; insurance-linked securities, capital raising, strategic advice, restructuring, and merger and acquisition services; and risk management products and solutions, capital market solutions, and corporate finance advisory services. In addition, the company offers strategic design advice and actuarial services; pension risk transfer and integrated pension administration; and investment advisory services on developing and maintaining investment programs across various plan types, including defined benefit plans, defined contribution plans, master trusts, and pooled employer plans for corporations, public pensions, endowments, and foundations. Aon plc was incorporated in 1979 and is headquartered in Dublin, Ireland.
What does it do?
Aon is a giant middleman in the world of insurance and risk. If a hospital wants to insure against lawsuits, or a multinational company wants to protect against cyberattacks, Aon helps them find the right insurance coverage at the best price — they don't sell insurance themselves, they broker it. They also help companies figure out how to pay and retain their employees, which is called 'human capital' consulting. Think of them as a professional problem-solver for risks that keep CEOs up at night.
Aon sits at the intersection of two trends that aren't going away: a world that's getting riskier (climate disasters, cyberattacks, political instability) and companies that need expert help navigating that risk. Their $13B acquisition of NFP in 2024 dramatically expanded their reach into the middle-market business segment, which is a massive and underpenetrated opportunity. At $68B market cap, the market is betting Aon can keep converting global uncertainty into steady fee income.
How does it make money?
Aon makes money primarily by charging commissions and fees when they place insurance policies on behalf of clients — if a company buys $10M of cyber insurance through Aon, Aon keeps a percentage of that premium. Their Risk Capital segment (commercial insurance brokerage, specialty risk) drove the bulk of their $17.2B in 2024 revenue, up from $15.7B the prior year — a 9.5% jump. The Human Capital segment adds another layer through consulting fees for employee benefits and compensation strategy. Because clients pay recurring fees year after year, the revenue is unusually predictable and sticky.
Why do investors care?
The core growth story is simple: as the world gets more complex and dangerous, demand for risk advisory grows. Aon's NFP acquisition added thousands of middle-market clients — small and mid-sized businesses that historically couldn't afford top-tier risk advice — opening up a new lane of growth. Investors also love the margin expansion story: Aon has been cutting costs and reinvesting in technology, which could push profits even higher without needing dramatically more revenue. For the thesis to work, Aon needs to successfully integrate NFP, keep winning large corporate clients, and avoid a major softening in insurance pricing.
Deep Dive
MemberA full investor briefing on Aon plc — history, leadership, risks, and outlook.