Marsh vs Usi: Professional Liability / E&O Insurance

Sole practitioners and regional CPA firms are the audience for USI Insurance Services and its AICPA program, underwritten by CNA. Marsh serves specialized sectors such as banking, venture capital and healthcare.

Kearny Risk organizes these comparisons for firms whose advice, content or technology creates professional exposures.Research updated 2026-09-25

What Are the Key Differences Between Marsh and USI Insurance Services Professional Liability (E&O) Insurance?

CPA Program vs Enterprise Verticals

USI's AICPA program targets CPA firms and names CNA as insurer. [7] Marsh serves banking, insurance, asset management, venture capital, professional services, media, technology and healthcare and does not name a carrier. [3]

Choose USI if you are a CPA firm eligible for the AICPA program and want its named insurer; choose Marsh if your company operates in one of its named enterprise sectors and needs specialist review. [7] [3]

Services With the Coverage

USI says AICPA members receive claims support and risk-management resources such as engagement-letter templates. [7] Marsh says attorneys, economists and actuaries assess client exposures with coverage specialists. [3]

What Should You Confirm in Marsh and USI Insurance Services Professional Liability (E&O) Insurance Quotes?

  • If you are a CPA, confirm whether USI's AICPA or Business Services placement applies. [7] [8]
  • Ask Marsh which carrier would issue the policy and compare limits and retentions. [3]
  • Ask which USI services apply to your firm. [7]

Areas of coverage

Marsh

  • role: Marsh's financial and professional liability practice places professional liability (errors and omissions) insurance; MMA also places E&O coverage within its executive and professional liability practice for middle-market clients. Marsh professional liability page and MMA executive and professional liability page.company-reportedSource ↗Source ↗
  • coverage: Marsh says professional liability coverage can protect a company against liability and defense costs from a claim alleging an error, omission or negligence in performing professional services, and that many policies also cover privacy violations and computer security breaches. Marsh professional liability page opening description; illustrative policy description, not a specific policy form.company-reportedSource ↗
  • eligibility: Marsh names specialized industries its professional liability experts serve, including banking and broker/dealers, insurance companies and asset managers, merchant banking and venture capital, accountants, attorneys, architects and engineers, media and entertainment, technology, and healthcare and biotechnology. Marsh professional liability page, What We Offer section.company-reportedSource ↗
  • insurer: The reviewed pages do not name a specific professional liability insurer. Marsh professional liability page and MMA executive and professional liability page as read on 2026-09-23.not-disclosedSource ↗Source ↗
  • services: Marsh says it employs attorneys, economists and actuaries alongside coverage specialists to assess a client's professional liability exposure from multiple angles, given the complexity of these risks. Marsh professional liability page.company-reportedSource ↗

USI Insurance Services

  • role: For CPA firms, USI runs the AICPA Professional Liability Program through its USI Affinity division as the endorsed producer, rather than underwriting the policy itself. USI's general Business Services practice separately brokers errors and omissions/professional liability coverage for other business types. AICPA program page and Business Services practice page.company-reportedSource ↗Source ↗
  • insurer: USI's own page states that the AICPA Professional Liability Program is "underwritten by CNA," naming the carrier for that specific program. USI's general Business Services E&O placements do not name an insurer. Direct quote from the AICPA program page; CNA underwrites only this named program, not USI's other professional-liability placements.company-reportedSource ↗
  • eligibility: USI markets the AICPA program to sole practitioners and regional CPA firms. It has offered CPA coverage since 1967 and has been the endorsed AICPA Program provider since 1994. Program page description.company-reportedSource ↗
  • coverage: USI describes the policy as insuring a CPA and their practice against third-party claims that professional services caused financial harm, providing a defense and paying damages for covered claims arising from high-risk situations tied to new clients, changing business plans, or new laws and regulations. Program page description; actual insuring agreements, exclusions and conditions are set by the issued CNA policy form.company-reportedSource ↗
  • limits: The AICPA program page does not publish limit, retention or premium figures; it says coverage plans allow a firm to tailor coverage to its risk profile. Page as read on 2026-09-23.not-disclosedSource ↗
  • services: USI says firms enrolled in the program get supportive claims handling and exclusive access to risk-management resources, including engagement-letter templates, in addition to the coverage itself. Program page description.company-reportedSource ↗
  • application: USI directs CPA firms seeking a quote or renewal to contact USI Affinity, with a dedicated Affinity_APL@usi.com address for the AICPA program specifically. Contact instructions on the AICPA program page.company-reportedSource ↗

USI's AICPA program names CNA for CPA firms and offers claims and risk-management resources; Marsh serves a wider set of enterprise sectors and describes specialist exposure review.

Sources reviewed

  1. 01
    Professional Liability – US Direct Errors and Omissions Insurance

    Hiscox Inc. specimen · About this Policy / Coverage for Claims Made Against You; I.A Insuring Agreement; I.B Defense; I.C Settlement; II.A Notice of Claims; II.C Optional Extended Reporting Period; III.A, III.K, III.M, III.R, III.S Exclusions; IV.A–B Limits and Deductible; VI.O Professional Services; VI.U Wrongful Act · accessed 2026-09-16

  2. 02
    Professional liability insurance

    Insurance Information Institute · Opening paragraphs (professional services/advice and E&O name); Claims not covered by general liability; What types of businesses need professional liability insurance?; What’s covered… and what’s not (claims-made versus occurrence, defense and judgments, non-financial/intentional limits, BOP/in-home exclusion) · accessed 2026-09-16

  3. 03
    Professional liability

    Marsh · Opening description; What We Offer: specialized industries served (banking, insurance/asset managers, merchant banking/venture capital, accountants/attorneys/architects/engineers, media/communications/entertainment, technology, healthcare/biotechnology) · accessed 2026-09-23

  4. 04
    Expert Executive and Professional Liability Insurance

    Marsh McLennan Agency · Our policies include D&O, E&O, EPL, commercial crime/fidelity, network security privacy risk/cyber, fiduciary, media liability, IP, architects and engineers, lawyers professional, and kidnap and ransom · accessed 2026-09-23

  5. 05
    FAQ: Professional liability insurance

    Texas Department of Insurance · What’s professional liability coverage?; What types of damages…; What’s general liability insurance?; Do I need professional liability… if I have general liability…?; Is professional liability insurance required?; Can a client require…?; What’s the difference between occurrence policies and claims-made policies · accessed 2026-09-16

  6. 06
    Get business insurance

    U.S. Small Business Administration · Six common types of business insurance table · accessed 2026-09-16

  7. 07
    Accountants Professional Liability — USI Affinity

    USI Insurance Services · Quality Professional Liability Insurance Exclusively for CPA Firms; "The AICPA Professional Liability Program, underwritten by CNA, has been offering coverage to CPAs since 1967 and has been the endorsed provider of the AICPA Program since 1994."; supportive claims handling and exclusive access to extensive risk management resources, including engagement letter templates; Email Affinity_APL@usi.com · accessed 2026-09-23

  8. 08
    Business Services

    USI Insurance Services · USI advises clients...and provides solutions for...Errors & Omissions/Professional Liability... · accessed 2026-09-23

  9. 09
    USI Specialty Program Solutions

    USI Insurance Services · USI Affinity delivers high-quality insurance and financial solutions to members of affinity organizations and targeted industry segments...for professional associations, law firms, alumni and collegiate organizations, travel groups, and insurance administrators. · accessed 2026-09-23

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