Aon vs Markel: Professional Liability / E&O Insurance

Areas of coverage

Aon

role: Aon presents Professional Liability / E&O as a line its Professional Services Practice helps arrange or advise on for professional-service firms. Aon is describing a global brokerage and advisory service, not issuing the underlying policy. The producing legal entity and carrier for any particular placement are not named on this page. Aon’s global professional-services practice page. This establishes a marketed brokerage/advisory offering, not policy issuance or account-specific placement.company-reportedSource ↗
eligibility: Aon identifies law, accounting and consulting firms as the audience for its global Professional Services Practice. That audience scope does not establish eligibility for every firm or other business. Audience described for Aon’s global professional-services practice. It does not establish U.S. state availability or underwriting eligibility for a placement.company-reportedSource ↗
coverage: Aon describes professional liability as addressing professional-services firms’ liability exposure and says it tailors coverage structures to a firm’s needs. It identifies E&O as a commonly used name for professional-liability insurance; actual policy terms are not stated. Aon’s marketing description of the brokerage/coverage area. The page is not the insurer’s policy form and does not establish an insured's entitlement to coverage.company-reportedSource ↗
services: Aon says its professional-services advisors use industry knowledge, insights, data and tools to support risk-management and human-capital decisions. This is a company-described advisory service, not a claim outcome or policy benefit. Company-reported advisory services on Aon’s global practice page; account-specific service scope is not stated.company-reportedSource ↗
insurer: The reviewed practice page does not name the insurer or producing legal entity for a specific placement. Ask for both on the quote and binder. Aon’s global practice page as reviewed 2026-09-30; no state-specific placement schedule or buyer quote was reviewed. This does not establish that Aon cannot arrange a placement.not-foundSource ↗
limits: The reviewed page does not state a buyer-specific limit, retention, deductible or other placement terms. Confirm these in the quote, bond or issued policy. Aon’s global practice page as reviewed 2026-09-30; no quote, bond form or issued policy was reviewed.not-disclosedSource ↗

Markel Insurance

role: Markel describes offering professional errors omissions for the audience stated on the cited product page. professional errors omissions marketed by markel; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement.company-reportedSource ↗
eligibility: Small businesses in ProBiz's targeted industries; source describes businesses up to $5 million revenue for the miscellaneous E&O product. professional errors omissions marketed by markel; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement.company-reportedSource ↗
coverage: The cited product page describes miscellaneous E&O for covered claims arising from professional services, with the page describing separate E&O and management-liability products. Marketing description only; actual coverage, exclusions, conditions, limits, and availability depend on the issued policy and jurisdiction. professional errors omissions marketed by markel; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement.company-reportedSource ↗
application: The page invites prospective customers or brokers to contact Markel or the named underwriting team. The page does not establish a quote, bind, or coverage-effective timeline. professional errors omissions marketed by markel; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement.company-reportedSource ↗
limits: For its miscellaneous E&O product, Markel states coverage up to $2 million; this is a product-page maximum, not a promise that every applicant or quote receives that amount. Markel ProBiz miscellaneous E&O marketing page; class, underwriting, policy terms, and actual quoted limit control.company-reportedSource ↗

What Are the Key Differences Between Aon and Markel Insurance Professional Liability (E&O) Insurance?

Professional Class and Product Scope

Aon says it tailors professional-liability structures to the needs of firms in law, accounting and consulting, but does not publish a limit. Markel describes miscellaneous E&O for small businesses in targeted industries and states coverage up to $2 million. Markel labels that figure a product maximum, not a promise for every applicant. Buyers can use it as a ceiling to discuss, then ask both firms what limit and retention fit the services and client contracts at issue. [1] [4]

Placement Detail and Buyer Decisions

Markel invites prospective customers or brokers to contact its underwriting team and says terms depend on the issued policy and jurisdiction. Aon likewise acts as a broker/adviser and does not name the carrier for a placement. Markel’s reviewed overview separates E&O from management liability but gives limited detail about covered acts. Request the specific form, exclusions, retroactive date and issuing insurer from both providers before comparing the $2 million headline with an actual quote. [1] [4]

What Should You Confirm in Aon and Markel Insurance Professional Liability (E&O) Insurance Quotes?

Ask Markel whether your industry qualifies and what limit below the $2 million maximum is offered. [1] [4]
Ask Aon for carrier, limit, deductible and the policy definition of professional services. [1] [4]

Aon describes tailored E&O structures for professional firms but publishes no limits. Markel describes miscellaneous E&O for small businesses in targeted industries, up to a stated $2 million product maximum.

Sources reviewed

01
Professional Services Practice
Aon · Named professional-services audiences and global advisory role, lines 125–128; line offerings and explanations lines 131–190; contact link lines 120–122. Global practice page; no U.S. state or account-specific placement schedule. · accessed 2026-09-30
02
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
03
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
04
ProBiz | Professional Liability Coverage
Markel · Miscellaneous E&O; types of covered professional-service errors; ProBiz target classes and process. · accessed 2026-09-30
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
06
Get business insurance
U.S. Small Business Administration · Six common types of business insurance table · accessed 2026-09-16