What Is Aon?
Aon’s U.S. Commercial Risk terms describe brokerage for certain insurance programs, while its Middle Market page describes a dedicated practice for mid-sized organizations across North America. The public materials reviewed do not identify the licensed producer or insurer for a particular placement. Ask which entity will produce each line and which insurer will issue the policy; request jurisdiction details for the proposed placement and ask how compensation and claim notice work for your account. 1,2
What Is Liberty Mutual Business Insurance?
Liberty Mutual spans small-commercial, commercial, specialty, surety, and reinsurance businesses. The insurer and distribution route depend on the product, so check the offer and policy before you compare terms. 4,5
What Is Professional Errors and Omissions (E&O) Insurance?
Professional liability can help pay defense costs and covered losses when a client says your advice or service caused financial harm. If customers rely on your work, list every service you provide and check the claims-made reporting and prior-work terms. 7,8,9,10
Key Differences in Professional Liability (E&O) Insurance
Professional Class and Product Scope
Aon describes professional liability as a structure tailored to professional-services firms’ needs, particularly law, accounting and consulting practices. Liberty Mutual’s specialty-program portfolio instead names a specific Physicians & Surgeons Professional program and marks it “PL Only.” That is a more occupation-specific route for medical professionals, while Aon’s stated audience centers on professional-service firms. A physician should confirm the Liberty program’s eligible specialties before comparing it with a brokered alternative. 3 6
Placement Detail and Buyer Decisions
Liberty Mutual says its programs are managed by program administrators and provides inquiry contacts, but the listing does not establish the form, limits, exclusions or issuing insurer. Aon’s overview also leaves carrier and account terms unstated. Liberty’s page does not describe online binding; applicants should ask its program contact or an agent how placement proceeds. Obtain actual policy forms and confirm whether the program is professional liability only as applied to your specialty. 3 6
What to Confirm in Professional Liability (E&O) Insurance Quotes
Review Scores
These averages can combine ratings for different products, locations, and customer groups, including approximate BBB grade conversions. Read each review for the sources, scope, and calculation.
Aon
Review Score
3 rated sources
Public ratings for Aon are low: Trustpilot shows 1.2 out of 5 from 782 reviews, and BBB shows 1.6 from five. Aon is a global firm, so those pages mostly reflect other parts of the business, not large U.S. commercial accounts.[4][6][7]
Read Aon reviewsLiberty Mutual
Review Score
2 rated sources
Customers give Liberty Mutual 4.2 out of 5 on Trustpilot from 3,836 reviews, but that page mixes auto, home and life customers with business ones. For business insurance specifically, NerdWallet gives 3.0 out of 5 and reports more complaints than expected.[4][1]
Read Liberty Mutual reviewsOffering Details
Aon vs Liberty Mutual: Professional Liability (E&O) Insurance: documented features by provider
| Criteria | Aon Professional Liability / E&O brokerage and risk-advisory offering | Physicians & Surgeons Professional program |
|---|---|---|
| Role in This Line | 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. 3Company-reported. Aon’s global professional-services practice page. This establishes a marketed brokerage/advisory offering, not policy issuance or account-specific placement. | Liberty Mutual lists a Physicians & Surgeons Professional program, marked “PL Only,” in its specialty-program portfolio. 6Company-reported. Official Liberty Mutual commercial/product page; company-reported description scoped to Physicians & Surgeons Professional program. Not policy wording, underwriting approval, state eligibility or a coverage guarantee. |
| Issuing 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. 3Not found in reviewed sources. 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. | Confirm in your quote. |
| Who It’s For | 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. 3Company-reported. Audience described for Aon’s global professional-services practice. It does not establish U.S. state availability or underwriting eligibility for a placement. | Liberty Mutual says its programs are managed by program administrators; the page provides program inquiry contact details. 6Company-reported. Official Liberty Mutual commercial/product page; company-reported description scoped to Physicians & Surgeons Professional program. Not policy wording, underwriting approval, state eligibility or a coverage guarantee. |
| Coverage Features | 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. 3Company-reported. 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. | The listing identifies professional liability only; it does not establish form terms, limits, exclusions or insurer for a quote. 6Company-reported. Official Liberty Mutual commercial/product page; company-reported description scoped to Physicians & Surgeons Professional program. Not policy wording, underwriting approval, state eligibility or a coverage guarantee. |
| Limits and Retentions | 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. 3Not publicly disclosed. Aon’s global practice page as reviewed 2026-09-30; no quote, bond form or issued policy was reviewed. | Confirm in your quote. |
| Risk 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. 3Company-reported. Company-reported advisory services on Aon’s global practice page; account-specific service scope is not stated. | Confirm in your quote. |
| How to Apply | Confirm in your quote. | The cited product page does not establish an online application or policy-binding path; ask the listed team or your broker/agent how this product is placed. 6Not found in reviewed sources. Reviewed product-page scope only. This not-found disposition is not a claim that no digital route exists. |
Full Comparison
More Aon vs Liberty Mutual Comparisons
Other Professional Liability (E&O) Insurance Comparisons
Sources
Aon
- Commercial Risk Solutions U.S. Brokerage Terms of Service. Aon; Lines 120–127: certain-program broker-of-record scope, consultation, application assistance, client signature and bind instruction, and account administration; lines 140–147: variable and contingent compensation, potential placement incentive, and client request route; lines 206–213: no price guarantee and surplus-lines limitations; lines 229–231: client insurer-notice duty unless separately agreed. Accessed 2026-09-29.
- Middle Market Clients. Aon; Lines 125–132: mid-sized organizations and middle-market framing; lines 165–173: dedicated practice and North America statement; lines 188–224: Commercial Risk capabilities. No numeric company-size cutoff or U.S.-only eligibility rule is stated on the reviewed page. Accessed 2026-09-29.
- 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.
Liberty Mutual
- Company Profile. Liberty Mutual Group; Strategic business units paragraph: US Retail Markets (individuals/small businesses; small commercial; countrywide) and Global Risk Solutions (mid-size/large businesses; commercial, specialty, reinsurance, surety; worldwide). Accessed 2026-09-29.
- Commercial Insurance Solutions. Liberty Mutual Business Insurance; Commercial solutions index names commercial auto and fleet, cyber, environmental liability, equipment breakdown, excess and surplus, general liability, healthcare liability, inland marine, management liability, multinational, ocean marine, professional liability, property, reinsurance, surety, umbrella/excess and workers compensation. Disclosure says policy insurer is named when offered, may be an affiliate/subsidiary or surplus-lines insurer; states/jurisdictions and actual policy terms vary. Accessed 2026-09-29.
- Programs. Liberty Mutual Business Insurance; ‘Our programs portfolio’ lists Auto Salvage/Dismantlers, Fire Suppression and Sprinkler Contractors, Nonprofits, Physicians & Surgeons Professional (PL only), Post-surgical for bariatric and plastic surgeries, Roofing Contractors, Scrap Metal Dealers, Self-storage, and Sports and Fitness. Page says programs are managed by program administrators; not a complete business catalogue. Accessed 2026-09-29.
Professional Liability (E&O) Insurance Guide
- 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.
- 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.
- Get business insurance. U.S. Small Business Administration; Six common types of business insurance table. Accessed 2026-09-16.
- 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.
