Insero & Co. CPAS, LLP
Employee benefit plan audit practice profile, built from plan year 2024 Form 5500 filings.
Last updated · Source data: plan year 2024 Form 5500 filings
How many 401(k) plans does Insero & Co. CPAS, LLP audit?
Insero & Co. CPAS, LLP was the independent auditor for 105 retirement plan filings (131 audited filings including welfare plans) in plan year 2024, with clients in 18 states and territories — the #104 practice nationally by volume.
Practice at a glance
| Measure | Value |
|---|---|
| Firm EIN (as filed) | 47-5324570 |
| Retirement plan audits (401(k), 403(b), pension) | 105 |
| All audited filings (incl. welfare plans) | 131 |
| States and territories with clients | 18 |
| National rank by retirement plan volume | #104 of 3,956 |
| National rank, all audited filings (league-table basis) | #95 of 4,052 |
| Average client size (participants) | 3,527 |
| Largest client (participants) | 34,518 |
Rankings derived from U.S. Department of Labor Form 5500 filings, plan year 2024. Read the full methodology.
Where does Insero & Co. CPAS, LLP audit plans?
| State | Plans audited | Share of practice |
|---|---|---|
| New York | 45 | 42.9% |
| Pennsylvania | 13 | 12.4% |
| New Jersey | 11 | 10.5% |
| Connecticut | 6 | 5.7% |
| California | 5 | 4.8% |
| Florida | 4 | 3.8% |
| Indiana | 3 | 2.9% |
| Massachusetts | 3 | 2.9% |
| Texas | 3 | 2.9% |
| Colorado | 2 | 1.9% |
| Illinois | 2 | 1.9% |
| Virginia | 2 | 1.9% |
| Maryland | 1 | 1.0% |
| Minnesota | 1 | 1.0% |
| North Carolina | 1 | 1.0% |
| New Hampshire | 1 | 1.0% |
| Oregon | 1 | 1.0% |
| South Dakota | 1 | 1.0% |
Largest concentration: New York (45 plans). State reflects the plan sponsor’s address, not the firm’s office locations.
What audit opinions does Insero & Co. CPAS, LLP issue?
| Opinion type | Filings | Share |
|---|---|---|
| Unmodified (clean) | 100 | 95.2% |
| Qualified | 0 | 0.0% |
| Disclaimer | 5 | 4.8% |
| Adverse | 0 | 0.0% |
As coded on Schedule H. A disclaimer here usually reflects the legacy limited-scope reporting convention (now the ERISA Section 103(a)(3)(C) election), not a failed audit — see the methodology.
Largest plans audited by Insero & Co. CPAS, LLP
| Plan sponsor | State | Participants |
|---|---|---|
| Eastman Kodak Company | NY | 34,518 |
| Corning Incorporated | NY | 33,672 |
| Frontier Communications Corporation | CT | 26,201 |
| Frontier Communications Parent, Inc. | CT | 22,881 |
| Paychex , Inc. | NY | 19,991 |
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About this profile
This page is generated from public U.S. Department of Labor Form 5500 filings in which Insero & Co. CPAS, LLP (EIN 47-5324570) is named as the plan’s independent qualified public accountant. Insero & Co. CPAS, LLP did not supply, review, or endorse this information, and inclusion is not a recommendation. Filing data can contain sponsor-entered errors; corrections are welcome via the about page.