---
title: "Aon vs Marsh: Professional Liability (E&O) Insurance"
description: "Aon tailors professional-liability structures for professional firms; Marsh describes defense costs and possible privacy or computer-security coverage."
canonical: "https://spot.insure/compare/aon-vs-marsh/professional-errors-omissions"
page-type: "line-comparison"
updated-at: "2026-09-30"
comparison-pair: "aon-vs-marsh"
provider-a: "aon"
provider-b: "marsh"
coverage-line: "professional-errors-omissions"
---

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[Human-readable page](https://spot.insure/compare/aon-vs-marsh/professional-errors-omissions)

## Agent Guide

**What this page is:** Focused comparison of Aon and Marsh for Professional Liability (E&O) Insurance: what each provider publishes about this line, checked against the same criteria, with numbered sources.

**Use this page when:** Cite or fetch this for Professional Liability (E&O) Insurance questions about Aon versus Marsh. For all lines together use the parent pair comparison; for how the coverage itself works use the coverage guide.

**Questions this page answers:**
- Aon vs Marsh for Professional Liability (E&O) Insurance: how do they differ?
- Which is better for Professional Liability (E&O) Insurance, Aon or Marsh?
- What does Aon or Marsh publish about Professional Liability (E&O) Insurance (limits, eligibility, claims, add-ons)?
- What should I confirm in a quote for Professional Liability (E&O) Insurance from Aon or Marsh?

**Key facts:**
- Line: Professional Liability (E&O) Insurance. Providers: Aon and Marsh.
- Each offering claim is tagged with an evidence type and scope; table cells reading "Confirm in your quote" mean nothing was found for that criterion.
- Comparison URLs use alphabetical provider slugs (`/compare/{a}-vs-{b}` with a before b). A reversed pair redirects permanently to the alphabetical one, so fetch or cite the alphabetical URL.

**Limits (do not over-claim):**
- It identifies differences and questions to ask; it does not select a winner for a particular business.
- "Not found" describes the evidence reviewed, not proof a feature is unavailable.
- Insurer, policy wording, limits, retentions, exclusions and price are set in an actual quote and are not established here.

**Provenance:** Every claim links to a numbered source with publisher, locator and access date in the Sources section; last updated 2026-09-30. Editorial policy: /editorial-policy.

**Related pages:**
- [Aon vs Marsh](https://spot.insure/compare/aon-vs-marsh) — parent: all coverage lines for this pair
- [Professional Liability (E&O) Insurance guide](https://spot.insure/coverage/professional-errors-omissions) — coverage explainer for this line
- [Aon profile](https://spot.insure/insurance-providers/aon) — provider profile (evidence)
- [Marsh profile](https://spot.insure/insurance-providers/marsh) — provider profile (evidence)
- [Aon vs Marsh Commercial Property Insurance](https://spot.insure/compare/aon-vs-marsh/commercial-property) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Crime Insurance](https://spot.insure/compare/aon-vs-marsh/crime) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Cyber Insurance](https://spot.insure/compare/aon-vs-marsh/cyber) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh D&O Insurance](https://spot.insure/compare/aon-vs-marsh/directors-officers) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Employment Practices Liability Insurance](https://spot.insure/compare/aon-vs-marsh/employment-practices) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Fiduciary Liability Insurance](https://spot.insure/compare/aon-vs-marsh/fiduciary) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Kidnap and Ransom Insurance](https://spot.insure/compare/aon-vs-marsh/kidnap-ransom) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Management Liability Insurance](https://spot.insure/compare/aon-vs-marsh/management-liability) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh Workers’ Compensation Insurance](https://spot.insure/compare/aon-vs-marsh/workers-compensation) — sibling comparison (other line, or other pair for this line)
- [AIG vs Aon Professional Liability (E&O) Insurance](https://spot.insure/compare/aig-vs-aon/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)
- [AIG vs Marsh Professional Liability (E&O) Insurance](https://spot.insure/compare/aig-vs-marsh/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)
- [Alliance Risk vs Aon Professional Liability (E&O) Insurance](https://spot.insure/compare/alliance-risk-vs-aon/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)
- [Alliance Risk vs Marsh Professional Liability (E&O) Insurance](https://spot.insure/compare/alliance-risk-vs-marsh/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)
- [Aon vs At-Bay Professional Liability (E&O) Insurance](https://spot.insure/compare/aon-vs-at-bay/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)
- [Aon vs The Baldwin Group Professional Liability (E&O) Insurance](https://spot.insure/compare/aon-vs-baldwin/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)

# Aon vs Marsh: How Do They Compare for Professional Liability (E&O) Insurance?

Aon tailors professional-liability structures for professional firms; Marsh describes defense costs and possible privacy or computer-security coverage.

## Research Scope and Use

Use this comparison to evaluate Aon and Marsh for Professional Liability (E&O) Insurance against the same documented criteria. It identifies differences and questions to confirm; it does not select a winner for a particular business. Offering claims are what each provider publishes about this line unless marked otherwise. “Not found” describes the evidence reviewed, not proof that a feature is unavailable. Confirm the insurer, policy wording, limits, retentions, exclusions and cost in an actual quote.

## Summary

Aon describes tailored professional-liability structures without form details. Marsh says E&O can cover liability and defense costs for alleged service errors and that many policies also cover privacy or computer-security claims. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability")

## 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](https://www.aon.com/en/about/leadership-and-governance/brokerage-terms-of-service-for-commercial-risk-solutions-us "Commercial Risk Solutions U.S. Brokerage Terms of Service") [2](https://www.aon.com/en/capabilities/middle-market-clients "Middle Market Clients")

[Aon profile](https://spot.insure/insurance-providers/aon)

## What Is Marsh?

Marsh suits technology and larger businesses seeking specialist cyber placement or broad global risk advice; small firms wanting a quick standard quote should compare its MMA route or digital agencies. [4](https://www.marsh.com/en/home.html "Marsh | Leader in risk, strategy, people, and investments") [5](https://www.marsh.com/content/dam/marsh/Documents/PDF/US-en/us-client-compensation-guide.pdf "Compensation guide for US clients") [6](https://www.marsh.com/en/services/marsh-mclennan-agency.html "Marsh McLennan Agency (MMA)") [7](https://www.marsh.com/en/industries/technology.html "Technology | Insurance Broking & Risk Management")

[Marsh profile](https://spot.insure/insurance-providers/marsh)

## 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. [10](https://www.tdi.texas.gov/commercial/pl-faq.html "FAQ: Professional liability insurance") [11](https://www.iii.org/article/professional-liability-insurance "Professional liability insurance") [12](https://www.sba.gov/counseling/launch-your-business/#business-insurance "Get business insurance") [13](https://www.hiscox.com/documents/pl-sample-policy-wording.pdf "Professional Liability – US Direct Errors and Omissions Insurance")

## Key Differences in Professional Liability (E&O) Insurance

### Professional Class and Product Scope

Aon says it tailors professional-liability structures for professional-services firms, but does not list coverage features on its practice overview. Marsh says E&O can respond to liability and defense costs for alleged errors, omissions or negligence in professional services; it adds that many policies also cover privacy violations and computer-security breaches. A buyer with blended professional and technology exposure should ask whether those extensions are actually in the Marsh form and compare them with Aon’s proposed wording. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability")

### Placement Detail and Buyer Decisions

Marsh names specialized fields including banking, venture capital, accounting, law, architecture, media, technology and healthcare, and says it uses attorneys, economists and actuaries alongside coverage specialists to assess exposures. Aon’s listed audience is law, accounting and consulting firms, with advisors using data and industry knowledge. Neither record names the carrier or publishes limits. Confirm the insurer, insured services definition and any cyber sublimit before treating the descriptions as comparable. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability")

## What to Confirm in Professional Liability (E&O) Insurance Quotes

- Ask Marsh whether privacy and computer-security claims are included, excluded or sublimited on the quote. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability")
- Ask Aon which carrier, professional-services definition and limits apply to your specific industry. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability")

## Offering Details

| Criteria | Aon Professional Liability / E&O brokerage and risk-advisory offering | Marsh Professional Liability Insurance Brokerage |
| --- | --- | --- |
| 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. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") (Evidence: Company-reported; scope: Aon’s global professional-services practice page. This establishes a marketed brokerage/advisory offering, not policy issuance or account-specific placement..) | 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. [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [9](https://www.marshmma.com/us/solutions/executive-and-professional-liability.html "Expert Executive and Professional Liability Insurance") (Evidence: Company-reported; scope: Marsh professional liability page and MMA executive and professional liability page..) |
| 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. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") (Evidence: Not found in reviewed sources; scope: 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..) | The reviewed pages do not name a specific professional liability insurer. [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") [9](https://www.marshmma.com/us/solutions/executive-and-professional-liability.html "Expert Executive and Professional Liability Insurance") (Evidence: Not publicly disclosed; scope: Marsh professional liability page and MMA executive and professional liability page as read on 2026-09-23..) |
| 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. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") (Evidence: Company-reported; scope: Audience described for Aon’s global professional-services practice. It does not establish U.S. state availability or underwriting eligibility for a placement..) | 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. [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") (Evidence: Company-reported; scope: Marsh professional liability page, What We Offer section..) |
| 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. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") (Evidence: Company-reported; scope: 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..) | 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. [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") (Evidence: Company-reported; scope: Marsh professional liability page opening description; illustrative policy description, not a specific policy form..) |
| 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. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") (Evidence: Not publicly disclosed; scope: 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. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") (Evidence: Company-reported; scope: Company-reported advisory services on Aon’s global practice page; account-specific service scope is not stated..) | 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. [8](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html "Professional liability") (Evidence: Company-reported; scope: Marsh professional liability page..) |

## Full Comparison

- [Aon vs Marsh](https://spot.insure/compare/aon-vs-marsh): all coverage lines, business roles, service and claims.
- [What Is Professional Errors and Omissions (E&O) Insurance?](https://spot.insure/coverage/professional-errors-omissions): Professional liability can help pay covered defense costs and losses when a client says your advice or service caused financial harm; check services and reporting terms.
- [Aon vs Marsh Commercial Property Insurance](https://spot.insure/compare/aon-vs-marsh/commercial-property)
- [Aon vs Marsh Crime Insurance](https://spot.insure/compare/aon-vs-marsh/crime)
- [Aon vs Marsh Cyber Insurance](https://spot.insure/compare/aon-vs-marsh/cyber)
- [Aon vs Marsh D&O Insurance](https://spot.insure/compare/aon-vs-marsh/directors-officers)
- [Aon vs Marsh Employment Practices Liability Insurance](https://spot.insure/compare/aon-vs-marsh/employment-practices)
- [Aon vs Marsh Fiduciary Liability Insurance](https://spot.insure/compare/aon-vs-marsh/fiduciary)
- [Aon vs Marsh Kidnap and Ransom Insurance](https://spot.insure/compare/aon-vs-marsh/kidnap-ransom)
- [Aon vs Marsh Management Liability Insurance](https://spot.insure/compare/aon-vs-marsh/management-liability)
- [Aon vs Marsh Workers’ Compensation Insurance](https://spot.insure/compare/aon-vs-marsh/workers-compensation)
- [AIG vs Aon Professional Liability (E&O) Insurance](https://spot.insure/compare/aig-vs-aon/professional-errors-omissions)
- [AIG vs Marsh Professional Liability (E&O) Insurance](https://spot.insure/compare/aig-vs-marsh/professional-errors-omissions)
- [Alliance Risk vs Aon Professional Liability (E&O) Insurance](https://spot.insure/compare/alliance-risk-vs-aon/professional-errors-omissions)
- [Alliance Risk vs Marsh Professional Liability (E&O) Insurance](https://spot.insure/compare/alliance-risk-vs-marsh/professional-errors-omissions)
- [Aon vs At-Bay Professional Liability (E&O) Insurance](https://spot.insure/compare/aon-vs-at-bay/professional-errors-omissions)
- [Aon vs The Baldwin Group Professional Liability (E&O) Insurance](https://spot.insure/compare/aon-vs-baldwin/professional-errors-omissions)

## Sources

### Aon

1. [Commercial Risk Solutions U.S. Brokerage Terms of Service](https://www.aon.com/en/about/leadership-and-governance/brokerage-terms-of-service-for-commercial-risk-solutions-us). 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.
2. [Middle Market Clients](https://www.aon.com/en/capabilities/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.
3. [Professional Services Practice](https://www.aon.com/en/capabilities/risk-transfer/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.

### Marsh

4. [Marsh | Leader in risk, strategy, people, and investments](https://www.marsh.com/en/home.html). Marsh; Hero and capability tiles; FAQ: What does Marsh do?; industries served; Is Marsh the same as Marsh McLennan? January 2026 brand change. Accessed 2026-09-16.
5. [Compensation guide for US clients](https://www.marsh.com/content/dam/marsh/Documents/PDF/US-en/us-client-compensation-guide.pdf). Marsh; US broking segments; broker role; retail commissions, client fees, wholesale, insurer consulting, contingent and supplemental commissions; Marsh LLC and Marsh USA LLC; page 3: broker role and Marsh & McLennan Agency segment; page 7: copyright © 2024 Marsh LLC. Accessed 2026-09-16.
6. [Marsh McLennan Agency (MMA)](https://www.marsh.com/en/services/marsh-mclennan-agency.html). Marsh; Middle-market US organizations; wholly-owned subsidiary; business insurance, employee health and benefits, retirement, private client. Accessed 2026-09-16.
7. [Technology | Insurance Broking & Risk Management](https://www.marsh.com/en/industries/technology.html). Marsh; Opening Technology Practice description; practice links including data center insurance, fintech and Stratus; Talk to us. Accessed 2026-09-16.
8. [Professional liability](https://www.marsh.com/en/services/financial-professional-liability/expertise/professional-liability.html). 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.
9. [Expert Executive and Professional Liability Insurance](https://www.marshmma.com/us/solutions/executive-and-professional-liability.html). 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.

### Professional Liability (E&O) Insurance Guide

10. [FAQ: Professional liability insurance](https://www.tdi.texas.gov/commercial/pl-faq.html). 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.
11. [Professional liability insurance](https://www.iii.org/article/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.
12. [Get business insurance](https://www.sba.gov/counseling/launch-your-business/#business-insurance). U.S. Small Business Administration; Six common types of business insurance table. Accessed 2026-09-16.
13. [Professional Liability – US Direct Errors and Omissions Insurance](https://www.hiscox.com/documents/pl-sample-policy-wording.pdf). 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.

Updated 2026-09-30. Spot, a product of Tools for Enlightenment, publishes this research and works in the commercial insurance market. The comparison applies the same criteria to both providers. [Editorial policy](https://spot.insure/editorial-policy). To suggest a correction, [contact Spot](https://spot.insure/contact) with the page URL and supporting source.

## Aon Reviews

Review Score: 6.1 / 10 from 3 rated sources, equally weighted.

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.

- J.D. Power: Aon study score 822 (out of 1000). Historical 2017 large-commercial-broker study; U.S. and Canada commercial insurance decision-makers at large organizations. J.D. Power reports 2,506 evaluations across the study, not Aon-specific responses; the Aon respondent count is not stated. Period: 2017 study; ranked 3rd among large commercial brokers; study-wide population 2,506, not Aon review count. Checked 2026-09-29. [Diversity of Offerings Becomes Key Differentiator for Large Commercial Insurers, JD Power Finds](https://www.jdpower.com/business/press-releases/jd-power-2017-large-commercial-insurance-study)
- Trustpilot: TrustScore 1.2 (out of 5); 782 reviews. Global www.aon.com profile merged with other Aon profiles; mixed experiences include pensions, travel, professional indemnity and Australian business quotation service. The two latter complaints are individual unverified allegations, not evidence of U.S. commercial-placement outcomes or insurer fault. Trustpilot says reviews may not be representative because the company has not recently invited reviews. Period: Displayed 2026-09-29; page separately showed 198 reviews in the last 12 months. Checked 2026-09-29. [Aon Reviews](https://www.trustpilot.com/review/www.aon.com)
- BBB: BBB business grade B− (BBB letter grade; stated reason: failure to respond to two filed complaints). BBB of Chicago & Northern Illinois profile for Aon plc; the business grade is BBB’s own measure, not customer stars. Checked 2026-09-29. [Aon plc | BBB Business Profile](https://www.bbb.org/us/il/chicago/profile/insurance-companies/aon-plc-0654-5291)
- BBB: BBB customer review average 1.6 (out of 5); 5 reviews. BBB of Chicago & Northern Illinois customer reviews for Aon plc; some reviews are about employee-benefit and medical-expense issues. Period: checked 2026-09-29. Checked 2026-09-29. [Aon plc | BBB Reviews](https://www.bbb.org/us/il/chicago/profile/insurance-companies/aon-plc-0654-5291/customer-reviews)

Reviewed 2026-09-29. [Read the sourced review](https://spot.insure/insurance-providers/aon/reviews).

## Marsh Reviews

Review Score: 5.8 / 10 from 2 rated sources, equally weighted.

Marsh’s global Trustpilot profile has a poor 1.3/5 score. Treat it as a service warning to investigate with your proposed team; it does not isolate US commercial accounts.

- Trustpilot: TrustScore 1.3 (0–5 stars); 115 reviews. Global brand profile across products/countries, not U.S. commercial-only. Period: 35 reviews in prior 12 months. Checked 2026-09-25. [Marsh Reviews | Trustpilot](https://www.trustpilot.com/review/www.marsh.com)
- Buzdy (Google review aggregation): Google reviews shown by Buzdy 4.5 (0–5 stars); 4 reviews. Named Marsh (Hong Kong) Limited office in Quarry Bay, Hong Kong. Buzdy states ratings/counts are powered by Google. Foreign local office only; not the U.S. Marsh brokerage or a firmwide score. Period: Listing verification 2026-07-29; accessed 2026-09-25. Checked 2026-09-25. [Marsh (Hong Kong) Limited | Buzdy](https://buzdy.com/viewMerchant/marsh-hong-kong-limited-hong-kong)

Reviewed 2026-09-25. [Read the sourced review](https://spot.insure/insurance-providers/marsh/reviews).

## Agent and Developer Resources

- [Markdown page](https://spot.insure/compare/aon-vs-marsh/professional-errors-omissions.md)
- [Developer resources](https://spot.insure/developers)
- [Public MCP server](https://spot.insure/mcp)
- [MCP server manifest](https://spot.insure/server.json)
- [OpenAPI description](https://spot.insure/openapi.json)
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