Marsh vs USI Insurance Services: How Do They Compare for 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.

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. ^3,¹

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. ³ Marsh serves banking, insurance, asset management, venture capital, professional services, media, technology and healthcare and does not name a carrier. ¹

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. ³ ¹

Services With the Coverage

USI says AICPA members receive claims support and risk-management resources such as engagement-letter templates. ³ Marsh says attorneys, economists and actuaries assess client exposures with coverage specialists. ¹

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. ³ ⁵
Ask Marsh which carrier would issue the policy and compare limits and retentions. ¹
Ask which USI services apply to your firm. ³

Marsh vs USI Insurance Services Professional Liability (E&O) Compared

Marsh vs USI Insurance Services: Professional Liability (E&O) Insurance: documented features by provider

Criteria	Marsh Professional Liability Insurance Brokerage	AICPA Professional Liability Program (USI Affinity)
Who It’s For	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. ¹Company-reported. Marsh professional liability page, What We Offer section.	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. ³Company-reported. Program page description.
Coverage Features	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. ¹Company-reported. Marsh professional liability page opening description; illustrative policy description, not a specific policy form.	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. ³Company-reported. Program page description; actual insuring agreements, exclusions and conditions are set by the issued CNA policy form.
Role in This Line	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. ^1,²Company-reported. Marsh professional liability page and MMA executive and professional liability page.	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. ^3,⁵Company-reported. AICPA program page and Business Services practice page.
Risk 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. ¹Company-reported. Marsh professional liability page.	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. ³Company-reported. Program page description.