Research
Data reports on the U.S. employee benefit plan audit market, computed from the same public Form 5500 dataset that powers this directory and published as citable pages with fixed figures, a methodology section, and machine-readable metadata.
Last updated · Source data: plan year 2024 Form 5500 filings
Published reports
The 401(k) Audit Market in 2026: Who Audits America's Retirement Plans
Eleven findings and four tables on market size, concentration, the Big Four, retirement-plan specialists, geography, plan sizes, and audit opinions, computed from all 77,427 audited Form 5500 filings for plan year 2024.
How to use these reports
Every figure is computed from U.S. Department of Labor EFAST2 Form 5500 bulk data (Schedule H accountant fields joined to the Form 5500 header) using the definitions on the methodology page. Reports keep their figures as published; the directory’s rankings, state pages, and firm profiles are refreshed with each DOL release and may move slightly as late filings arrive. Quote with attribution to 401k Audit Scout and a link to the report cited; each report carries a suggested citation.