Aon Corporation 401(k) Review & Grade
Aon Savings Plan
Atlanta, GAFinance & Insurance13,722 active participantsPlan year 2024✓ Auto-enroll
Estimate from the plan's Form 5500 filing · How we grade
$8,003Employer $ per active participant
$12,394Employee $ saved per active participant
0.03%Direct admin cost, % of plan assets
$6.6BNet plan assets, end of year
$271,805Average balance per account
Score breakdown
- Employer generosity38.0 / 5076th percentile for employer $ per participant
- Low cost21.0 / 2584th percentile for low admin cost vs. same-size plans
- Employee saving12.5 / 1583th percentile for employee $ per participant
- Plan features10 / 10Auto-enrollment, Default investment
Total score82 / 100 · Grade A
This plan vs. peers
Peers: Finance & Insurance plans with 10,000+ active participants (72 plans).
| Measure | Percentile |
|---|---|
| Employer $ per participant | 76th |
| Lower admin cost | 84th |
| Employee saving | 83th |
| Peers that auto-enroll | 74% |
Red flags from the filing
No red flags were reported on this filing's compliance questions.
What to do if you're in this plan
- Aon put in about $8,003 per active participant, more than the typical peer ($5,179). Contribute at least enough to collect the full match. Skipping it leaves part of your pay on the table.
- The filing shows total dollars, not the match formula. Ask HR for the Summary Plan Description so you know the exact match and vesting schedule.
- Fund expense ratios aren't in the filing. Look them up in your 404(a)(5) fee disclosure and favor low-cost index or target-date funds.
- The plan auto-enrolls employees. Check your default contribution rate. Defaults are often lower than what it takes to get the full match.
- Changing jobs? You can usually leave the money in the plan, move it to your new employer's plan, or roll it into an IRA. Don't cash out: you'd owe taxes and possibly a 10% penalty.
The raw numbers from the filing
| Employer contributions | $109,813,839 |
| Participant (employee) contributions | $170,069,538 |
| Other contributions (incl. rollovers in) | $22,592,454 |
| Administrative expenses paid from the plan | $1,865,744 |
| Contract administrator fees | $324,611 |
| Investment advisory & management fees | $724,729 |
| Other admin expenses | $1,948 |
| Benefits paid out | $700,052,508 |
| Net assets, start / end of year | $6.1B / $6.6B |
| Active participants, start / end of year | 13,974 / 13,470 |
| Participants with account balances | 24,239 |
| Auto-enrollment (feature code 2S) | Yes |
| Auditor | Ernst & Young, LLP |
Largest service providers (Schedule C)
| The Northern Trust Co | $658,497 reported compensation |
| Alight Solutions | $551,571 reported compensation |
| The Vanguard Group | $308,831 reported compensation |
Source: DOL EFAST2 Form 5500 filing, acknowledgment ID 20251007210454NAL0004989073001, received 2025-10-07, EIN 36-3051915, plan #020, plan year 2024-01-01 to 2024-12-31. Verify at efast.dol.gov.
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