Aon plc

Aon plc is a global professional services firm that provides risk capital and human capital advisory, brokerage, and solutions to clients in over 120 countries, generating $17.2 billion in revenue in fiscal 2025. The firm is one of the world's two largest insurance brokers, alongside Marsh McLennan, and competes across commercial risk brokerage, reinsurance intermediation, health and benefits consulting, and wealth solutions. It employs roughly 60,000 people and serves clients ranging from multinational corporations to middle-market businesses, with less than 2% of revenue coming from small commercial or personal lines.

This is a story about an incumbent services franchise converting structural advantages — proprietary data, global reach, and deeply embedded client relationships — into a compounding machine that appears increasingly difficult for competitors to replicate. The firm is in the final year of a three-year restructuring and investment programme that has reshaped its operating model around an integrated analytics platform called Aon Business Services, or ABS, while simultaneously absorbing the largest acquisition in its history: the $13.4 billion purchase of middle-market broker NFP in 2024. The file turns on a single question: whether the ABS-enabled flywheel — more data yielding better analytics, better analytics winning more clients, more clients generating more data — produces genuinely durable organic growth through the cycle, or whether the current mid-single-digit growth prints are simply riding a favourable insurance pricing tailwind that will fade.