Aon lifts Client Treaty co-insurance share to 35% for 2027

Aon renewed its Client Treaty for 2027, lifting the automatic co-insurance share of eligible placements to 35% from 28.5%, Insurance Business America reported Nov. 5.

Led by QBE and backed by Lloyd's syndicates, the facility now automatically co-insures 35% of eligible placements, providing prearranged capacity that follows the lead insurer's terms and pricing. From Jan. 1, it will cover eligible business placed through Aon's Global Broking Centre and facultative reinsurance placed by Aon Reinsurance Solutions. The 1.5% client dividend is unchanged and will apply to the larger share where law and regulation permit.

For Aon clients, the higher automatic co-insurance share commits a larger portion of each eligible placement to the QBE-led panel at the lead insurer's terms. Insurance Business America reported that underwriters outside the facility will compete for the smaller residual share, which could add to pricing pressure on specialty and large commercial layers.

The treaty has placed more than $5 billion in gross written premium since 2016, according to Insurance Business America. Helene Madell, chief executive of Aon's Global Broking Centre, said facultative reinsurance, added to the facility in late 2025, had quickly become one of its most important areas of growth.

Aon's Sidecar X facility put $200 million behind transactional risk, as Private Wealth Daily previously reported. The 2027 terms take effect Jan. 1.