Aon 401(k) match, vesting and fees
What Aon's 401(k) plan says about matching contributions
Plan features
Match, vesting and enrollment details have not been published from this plan's audit report yet. The figures below come from the structured filing.
| Recordkeeper | The Vanguard Group, Inc. | Schedule C ↗ |
| Independent auditor | Ernst & Young,llp (unmodified opinion, limited scope) | Schedule H ↗ |
| Plan type and status | 401(k) · Active | Form 5500 ↗ |
How the plan compares
Plan year 2025 medians for 31 defined-contribution plans in finance and insurance with 10,000 to 49,999 participants.
| Aon: employer contribution per participant | $4,731 | |
| Peer median | $4,274 |
| Aon: average balance | $312,093 | |
| Peer median | $186,787 |
| Aon: admin expenses ÷ assets | <0.01% | |
| Peer median | 0.04% |
Admin expenses are the plan's reported administrative expenses divided by its assets; they do not include fund expense ratios.
Plan history
Plan assets went from $6.5B at the end of plan year 2021 to $7.4B at the end of plan year 2025.
| Plan year | Participants | Assets | Employer contributions | Per participant | Admin expense ratio | Match formula | Filing |
|---|---|---|---|---|---|---|---|
| 2025 | 24,043 | $7.4B | $111M | $4,731 | <0.01% | Not published | Form 5500 ↗ |
| 2024 | 24,731 | $6.6B | $110M | $4,530 | 0.03% | Not published | Form 5500 ↗ |
| 2023 | 25,092 | $6.1B | $108M | $4,397 | 0.04% | Not published | Form 5500 ↗ |
| 2022 | 25,261 | $5.3B | $99.7M | $4,024 | 0.08% | Not published | Form 5500 ↗ |
| 2021 | 23,894 | $6.5B | $94.7M | $3,995 | 0.10% | Not published | Form 5500 ↗ |
Other Aon plans (2)
Each plan files its own Form 5500. Figures are from each plan's latest filing.
Aon Retirement Pension Plan
Plan features
Match, vesting and enrollment details have not been published from this plan's audit report yet. The figures below come from the structured filing.
| Independent auditor | Ernst & Young, LLP (unmodified opinion) | Schedule H ↗ |
| Plan type and status | Pension (defined benefit) · Frozen | Form 5500 ↗ |
Aon Pension Plan
Plan features
Match, vesting and enrollment details have not been published from this plan's audit report yet. The figures below come from the structured filing.
| Independent auditor | Ernst & Young, LLP (unmodified opinion) | Schedule H ↗ |
| Plan type and status | Pension (defined benefit) · Terminated (final filing) | Form 5500 ↗ |
Common questions
Does Aon match 401(k) contributions?
The match terms for the Aon Savings Plan have not been published from its filing yet. The plan year 2025 filing reports $111M in employer contributions, about $4,731 per participant. That total includes any match and profit-sharing; it is not a match formula.
When is the Aon 401(k) match vested?
The vesting schedule for the Aon Savings Plan is not in the data published so far. Your Summary Plan Description states it.
Who manages the Aon 401(k)?
The recordkeeper listed on Schedule C of the plan year 2025 filing is The Vanguard Group, Inc.. The plan administrator is Administrative Committee.
I left Aon. How do I find my old 401(k)?
Your account stays in the plan until you move it. Contact the plan administrator (Administrative Committee, (312) 381-1000) or the recordkeeper, The Vanguard Group, Inc.. The Aon old 401(k) page lists the contacts from every plan filing. Find an old Aon 401(k)
Data from the public Form 5500 annual reports Aon filed with the U.S. Department of Labor (plan years 2021 and 2022 and 2023 and 2024 and 2025) and, where noted, the attached independent auditor's report. Plan terms may have changed since the filing; check your current Summary Plan Description. PlanFacts is not affiliated with Aon. Not financial advice. Report a correction · Methodology