Aon picks Vanguard as recordkeeper and trustee of its $4.9 billion pooled employer plan

Aon PLC has chosen Vanguard as recordkeeper and trustee of the Aon Pooled Employer Plan, replacing Voya Financial in a role it has held since the PEP's 2021 launch; the plan's 2025 Form 5500 shows $4.915 billion in assets and more than 87,000 participants. Aon's September 2 count is larger still—about $7.7 billion across more than 160 employers and 103,000 participants, up from the $5 billion the firm announced in August 2025.

The announced changes run mostly to investments and services: Aon plans to widen access to Vanguard's target-date shelf and core index strategies and to add the advice solutions, educational content and financial wellness resources available through Vanguard, alongside what the announcement describes as more coordinated plan administration. Participating employers keep control of matching contributions, eligibility requirements and vesting schedules.

Rick Jones, Aon's senior partner of wealth solutions who leads the PEP, calls the selection an "evolution and enhancement" and points to the "scale, efficiency, cost savings [and] participant-focused resources that Vanguard can add to the equation." He says all participating employers and plan participants will see savings on the regular and ongoing charges for administering and participating in the plan, plus additional resources "at attractive rates."

The market those claims sit in is still small next to the rest of the defined contribution business, but it is compounding. At the end of 2025, 330 PEPs covering 10,797 adopting employers and more than 1.2 million participants held $34 billion, according to the 2026 PLANSPONSOR Recordkeeping Survey. Voya recordkept the most PEP assets among respondents, $6.198 billion, ahead of Transamerica Retirement Solutions at $5.353 billion and Principal Financial Group at $4.684 billion.

Aon sat out the survey and says in its 2026 promotional materials that it has more than $6 billion in PEP assets. By the firm's own numbers, this one plan exceeds the $6.198 billion that leads the survey, though the two sources do not support a clean comparison—one covers only respondents and the other is a sponsor's promotional figure.

Transamerica said yesterday that its pooled plan book, which bundles PEPs, multiple employer plans and group plan solutions, grew to $34.2 billion last year, up nearly 61% from $21.3 billion in 2021, with adopting employers up nearly 40% over the same stretch. That measures one firm's book rather than the surveyed market, and both grew fast enough over five years to explain why recordkeepers are bidding for this business.

For an employer already in the Aon PEP, the practical questions are what the fee line looks like once recordkeeping and trustee duties sit with a single provider, and whether that shelf displaces what is in the lineup today. No transition date is given, and the cost savings Jones describes arrive without a number attached to them.