401(k) Audit Firms in Illinois
Last updated · Source data: plan year 2024 Form 5500 filings
Who audits the most 401(k) plans in Illinois?
Sikich CPA LLC audited 228 Illinois plans in plan year 2024, the most of any firm. Overall, 387 firms audited 3,540 plans sponsored in Illinois; the median audited plan had 397 participants.
Top audit firms for Illinois plans
| # | Firm | IL plans audited |
|---|---|---|
| 1 | Sikich CPA LLC | 228 |
| 2 | CliftonLarsonAllen LLP | 221 |
| 3 | Plante & Moran, PLLC | 206 |
| 4 | Crowe LLP | 155 |
| 5 | RSM US LLP | 151 |
| 6 | Forvis Mazars, LLP | 150 |
| 7 | Miller Cooper & Co., LTD | 124 |
| 8 | Grant Thornton LLP | 112 |
| 9 | Baker Tilly US, LLP | 110 |
| 10 | Smith & Howard, PC | 106 |
| 11 | Legacy Professionals LLP | 86 |
| 12 | Cassell Plan Audits | 78 |
| 13 | FGMK, LLC | 76 |
| 14 | Wipfli LLP | 73 |
| 15 | Cherry Bekaert LLP | 63 |
| 16 | CBIZ CPAS P.C. | 45 |
| 17 | Kerber, Eck & Braeckel LLP | 43 |
| 18 | Calibre CPA Group, PLLC | 43 |
| 19 | Ernst & Young LLP | 42 |
| 20 | Porte Brown LLC | 37 |
| 21 | Selden Fox, LTD. | 36 |
| 22 | DHJJ LTD | 33 |
| 23 | Mitchell & Titus, LLP | 29 |
| 24 | MH CPA PLLC | 29 |
| 25 | BDO USA, P.C. | 28 |
Rankings derived from U.S. Department of Labor Form 5500 filings, plan year 2024. Read the full methodology.
Illinois plan audit market at a glance
| Measure | Value |
|---|---|
| Audited plans sponsored in Illinois | 3,540 |
| Audit firms with at least one IL engagement | 387 |
| Median audited plan size (participants) | 397 |
| Share of all U.S. audited plans | 4.6% |
Choosing an audit firm in Illinois
Engagement volume is the most objective public signal of employee benefit plan audit experience: the Department of Labor’s audit quality study found deficiency rates of 76% among CPAs performing one or two plan audits a year, versus 12% at the largest practices. The table above shows which firms do this work in Illinois at real volume.
Beyond volume, ask candidate firms about AICPA Employee Benefit Plan Audit Quality Center membership, who staffs the fieldwork, experience with your recordkeeper and payroll systems, and whether the fee assumes an ERISA Section 103(a)(3)(C) election. A Illinois address is not required — plan audits are performed remotely under the same national standards — but local presence can simplify scheduling and walkthroughs.