---
title: "Aon vs Marsh McLennan Agency: Commercial Auto Insurance"
description: "Marsh McLennan Agency lists commercial auto among its business coverage options; Aon lists Automobile Liability for law, accounting, and consulting firms."
canonical: "https://spot.insure/compare/aon-vs-marsh-mclennan-agency/commercial-auto"
page-type: "line-comparison"
updated-at: "2026-10-01"
comparison-pair: "aon-vs-marsh-mclennan-agency"
provider-a: "aon"
provider-b: "marsh-mclennan-agency"
coverage-line: "commercial-auto"
---

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[Human-readable page](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/commercial-auto)

## Agent Guide

**What this page is:** Focused comparison of Aon and Marsh McLennan Agency for Commercial Auto 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 Commercial Auto Insurance questions about Aon versus Marsh McLennan Agency. 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 McLennan Agency for Commercial Auto Insurance: how do they differ?
- Which is better for Commercial Auto Insurance, Aon or Marsh McLennan Agency?
- What does Aon or Marsh McLennan Agency publish about Commercial Auto Insurance (limits, eligibility, claims, add-ons)?
- What should I confirm in a quote for Commercial Auto Insurance from Aon or Marsh McLennan Agency?

**Key facts:**
- Line: Commercial Auto Insurance. Providers: Aon and Marsh McLennan Agency.
- 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 2026-10-01. Editorial policy: /editorial-policy.

**Related pages:**
- [Aon vs Marsh McLennan Agency](https://spot.insure/compare/aon-vs-marsh-mclennan-agency) — parent: all coverage lines for this pair
- [Commercial Auto Insurance guide](https://spot.insure/coverage/commercial-auto) — coverage explainer for this line
- [Aon profile](https://spot.insure/insurance-providers/aon) — provider profile (evidence)
- [Marsh McLennan Agency profile](https://spot.insure/insurance-providers/marsh-mclennan-agency) — provider profile (evidence)
- [Aon vs Marsh McLennan Agency Builders Risk Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/builders-risk) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Cargo and Transit Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/cargo-transit) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Commercial Property Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/commercial-property) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Crime Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/crime) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Cyber Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/cyber) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency D&O Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/directors-officers) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Employment Practices Liability Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/employment-practices) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Fiduciary Liability Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/fiduciary) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency General Liability Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/general-liability) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Kidnap and Ransom Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/kidnap-ransom) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Professional Liability (E&O) Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/professional-errors-omissions) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Surety Bonds](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/surety-bonds) — sibling comparison (other line, or other pair for this line)
- [Aon vs Marsh McLennan Agency Workers’ Compensation Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/workers-compensation) — sibling comparison (other line, or other pair for this line)
- [AIG vs Aon Commercial Auto Insurance](https://spot.insure/compare/aig-vs-aon/commercial-auto) — sibling comparison (other line, or other pair for this line)
- [AIG vs Marsh McLennan Agency Commercial Auto Insurance](https://spot.insure/compare/aig-vs-marsh-mclennan-agency/commercial-auto) — sibling comparison (other line, or other pair for this line)
- [Alliance Risk vs Aon Commercial Auto Insurance](https://spot.insure/compare/alliance-risk-vs-aon/commercial-auto) — sibling comparison (other line, or other pair for this line)
- [Alliance Risk vs Marsh McLennan Agency Commercial Auto Insurance](https://spot.insure/compare/alliance-risk-vs-marsh-mclennan-agency/commercial-auto) — sibling comparison (other line, or other pair for this line)
- [Aon vs The Baldwin Group Commercial Auto Insurance](https://spot.insure/compare/aon-vs-baldwin/commercial-auto) — sibling comparison (other line, or other pair for this line)
- [Aon vs biBerk Commercial Auto Insurance](https://spot.insure/compare/aon-vs-biberk/commercial-auto) — sibling comparison (other line, or other pair for this line)

# Aon vs Marsh McLennan Agency: How Do They Compare for Commercial Auto Insurance?

Marsh McLennan Agency lists commercial auto among its business coverage options; Aon lists Automobile Liability for law, accounting, and consulting firms.

## How to Use the Aon vs Marsh McLennan Agency Commercial Auto Insurance Comparison

Use this comparison to evaluate Aon and Marsh McLennan Agency for Commercial Auto 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.

## Aon vs Marsh McLennan Agency Commercial Auto Insurance Summary

Marsh McLennan Agency lists commercial auto among its business coverage options. Aon identifies law, accounting, and consulting firms as the audience for its Professional Services Practice, where it lists Automobile Liability. [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice") [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA")

## 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 McLennan Agency?

Marsh McLennan Agency provides business insurance and employee health and benefits, alongside retirement, wealth, and private-client services across the United States and Canada. Its US small-business page lists six common coverage types and directs buyers to request a personalized quote by phone; the insurer and terms for a specific placement must be confirmed in the proposal. [4](https://www.marshmma.com/us/mma/about-us.html "Who We Are") [5](https://www.marshmma.com/us/solutions/small-business.html "Small Business Insurance Solutions")

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

## What Is Commercial Auto Insurance?

Commercial auto suits businesses that use vehicles for work and need liability protection; damage to your own vehicles is a separate coverage choice. If employees drive personal or rented cars, check how those trips are handled. [7](https://www.insurance.ca.gov/01-consumers/105-type/95-guides/09-comm/commercialguide.cfm "Commercial Insurance Guide") [8](https://content.naic.org/insurance-topics/auto-insurance "Auto Insurance") [9](https://www.iii.org/publication/insuring-your-business-small-business-owners-guide-to-insurance/specific-coverages/business-vehicle-insurance "Business Vehicle Insurance") [10](https://nationalgeneral.com/forms_catalog/CA0001_10012013.pdf "Business Auto Coverage Form")

## What Are the Key Differences Between Aon and Marsh McLennan Agency Commercial Auto Insurance?

### Advice and Audience

Marsh McLennan Agency’s business-insurance overview lists commercial auto among its coverage options. Aon lists Automobile Liability within a Professional Services Practice for law, accounting, and consulting firms. The first is a line within a general business-coverage menu; the second names a specific audience for an automobile-liability offering. A company should ask both organizations which policy and underwriting market can address its actual operation. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice")

### Auto Liability or Business Coverage

Marsh McLennan Agency’s cited overview lists commercial auto as a business coverage option; Aon specifically labels its Professional Services offering “Automobile Liability.” A business comparing those labels should ask MMA which auto protections its proposal includes and ask Aon for the liability form and any separate physical-damage coverage. The source pages describe offerings, not the final insurer terms. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice")

## What Should You Confirm in Aon and Marsh McLennan Agency Commercial Auto Insurance Quotes?

- Which vehicles, drivers, states, and business operations will MMA review, and which professional-services audience does Aon consider for this placement? [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice")
- Who is the insurer and producing entity, and what limits, deductibles, and physical-damage terms will appear in the quote? [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") [3](https://www.aon.com/en/capabilities/risk-transfer/professional-services-practice "Professional Services Practice")

## Aon vs Marsh McLennan Agency Commercial Auto Insurance Compared

| Criteria | Aon Automobile Liability brokerage and risk-advisory offering | Marsh McLennan Agency commercial auto (official overview) |
| --- | --- | --- |
| Role in This Line | Aon presents Automobile Liability 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 McLennan Agency describes arranging commercial auto for the audience stated on the cited product page. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") (Evidence: Company-reported; scope: commercial auto marketed by marsh-mclennan-agency; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement..) |
| 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..) | 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. [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..) | Organizations seeking business insurance; the source says advisers analyze operations, assets, liabilities, and loss exposures. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") (Evidence: Company-reported; scope: commercial auto marketed by marsh-mclennan-agency; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement..) |
| Coverage Features | Aon lists Automobile Liability in its property-and-casualty offerings for professional services firms. The page does not describe covered autos, drivers, liability limits or policy terms. [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..) | The cited product page describes commercial-auto insurance as one of the business coverage types the agency places; the overview does not state policy terms. Marketing description only; actual coverage, exclusions, conditions, limits, and availability depend on the issued policy and jurisdiction. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") (Evidence: Company-reported; scope: commercial auto marketed by marsh-mclennan-agency; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement..) |
| 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..) | The cited overview does not set a universal limit or retention for this line. Ask for the proposed policy form, limits, retentions, exclusions, and conditions in the quote. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") (Evidence: Not publicly disclosed; scope: Only the cited marketing page was reviewed for published limit and retention information; no policy-form entitlement is inferred..) |
| 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..) | Confirm in your quote. |
| How to Apply | Confirm in your quote. | The page invites organizations to contact a Marsh McLennan Agency adviser or specialist to discuss placement. The page does not establish a quote, bind, or coverage-effective timeline. [6](https://www.marshmma.com/us/services/business-insurance.html "Business Insurance | MMA") (Evidence: Company-reported; scope: commercial auto marketed by marsh-mclennan-agency; scope is limited to the cited official product overview and described audience. This is not a policy form or a universal eligibility statement..) |

## Related Pages for Aon vs Marsh McLennan Agency Commercial Auto

- [Aon vs Marsh McLennan Agency](https://spot.insure/compare/aon-vs-marsh-mclennan-agency): all coverage lines, business roles, service and claims.
- [What Is Commercial Auto Insurance?](https://spot.insure/coverage/commercial-auto): Commercial auto covers liability from vehicles used for work, with vehicle damage and employee personal or rented cars requiring separate quote checks.
- [Aon vs Marsh McLennan Agency Builders Risk Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/builders-risk)
- [Aon vs Marsh McLennan Agency Cargo and Transit Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/cargo-transit)
- [Aon vs Marsh McLennan Agency Commercial Property Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/commercial-property)
- [Aon vs Marsh McLennan Agency Crime Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/crime)
- [Aon vs Marsh McLennan Agency Cyber Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/cyber)
- [Aon vs Marsh McLennan Agency D&O Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/directors-officers)
- [Aon vs Marsh McLennan Agency Employment Practices Liability Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/employment-practices)
- [Aon vs Marsh McLennan Agency Fiduciary Liability Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/fiduciary)
- [Aon vs Marsh McLennan Agency General Liability Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/general-liability)
- [Aon vs Marsh McLennan Agency Kidnap and Ransom Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/kidnap-ransom)
- [Aon vs Marsh McLennan Agency Professional Liability (E&O) Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/professional-errors-omissions)
- [Aon vs Marsh McLennan Agency Surety Bonds](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/surety-bonds)
- [Aon vs Marsh McLennan Agency Workers’ Compensation Insurance](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/workers-compensation)
- [AIG vs Aon Commercial Auto Insurance](https://spot.insure/compare/aig-vs-aon/commercial-auto)
- [AIG vs Marsh McLennan Agency Commercial Auto Insurance](https://spot.insure/compare/aig-vs-marsh-mclennan-agency/commercial-auto)
- [Alliance Risk vs Aon Commercial Auto Insurance](https://spot.insure/compare/alliance-risk-vs-aon/commercial-auto)
- [Alliance Risk vs Marsh McLennan Agency Commercial Auto Insurance](https://spot.insure/compare/alliance-risk-vs-marsh-mclennan-agency/commercial-auto)
- [Aon vs The Baldwin Group Commercial Auto Insurance](https://spot.insure/compare/aon-vs-baldwin/commercial-auto)
- [Aon vs biBerk Commercial Auto Insurance](https://spot.insure/compare/aon-vs-biberk/commercial-auto)

## Sources for Aon vs Marsh McLennan Agency Commercial Auto Insurance

### Sources About 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.

### Sources About Marsh McLennan Agency

4. [Who We Are](https://www.marshmma.com/us/mma/about-us.html). Marsh McLennan Agency; Lines 193-195: ‘a business of Marsh’ and company-listed service lines across US and Canada. This does not establish the legal entity for an account, corporate ownership chart, or insurer role.. Accessed 2026-09-29.
5. [Small Business Insurance Solutions](https://www.marshmma.com/us/solutions/small-business.html). Marsh McLennan Agency; Lines 205-207: small-business audience and call invitation; lines 224-249 list six coverage categories and short descriptions; line 264 is an embedded form whose function is not stated. No form submitted.. Accessed 2026-09-29.
6. [Business Insurance | MMA](https://www.marshmma.com/us/services/business-insurance.html). Marsh McLennan Agency; Business insurance coverage options; commercial auto is specifically listed among business insurance types.. Accessed 2026-09-30.

### Sources for the Commercial Auto Insurance Guide

7. [Commercial Insurance Guide](https://www.insurance.ca.gov/01-consumers/105-type/95-guides/09-comm/commercialguide.cfm). California Department of Insurance; Commercial Automobile: Coverage, Classification and Limits. Accessed 2026-09-16.
8. [Auto Insurance](https://content.naic.org/insurance-topics/auto-insurance). NAIC; Coverages. Accessed 2026-09-16.
9. [Business Vehicle Insurance](https://www.iii.org/publication/insuring-your-business-small-business-owners-guide-to-insurance/specific-coverages/business-vehicle-insurance). Insurance Information Institute; Will My Personal Auto Policy Cover Business Use?; What Vehicles Are Covered?; What Coverage Do I Need if Employees Drive Their Personal Vehicles for Business?; Does a Business Umbrella Cover Autos?; Do I Need a Business Auto Policy?; Be Sure the Right Insured Is on the Policy. Accessed 2026-09-16.
10. [Business Auto Coverage Form](https://nationalgeneral.com/forms_catalog/CA0001_10012013.pdf). Insurance Services Office, Inc.; hosted by National General; I.A, printed/PDF page 1; II.A.1, printed/PDF page 2; III.C–D, printed/PDF page 6; II.B.6, printed/PDF page 3; III.B.3, printed/PDF page 6. Accessed 2026-09-16.

Updated 2026-10-01. 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 Review Scores for 2026

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 McLennan Agency Review Scores for 2026

Review Score: 8.2 / 10 from 2 rated sources, equally weighted.

There are almost no public customer reviews of Marsh McLennan Agency (MMA). Trustpilot shows 3.2 out of 5, but from a single review, and BBB shows an A grade with four complaints closed in three years.

- Trustpilot: TrustScore 3.2 (out of 5); 1 reviews. Trustpilot profile for marshmma.com, MMA's own domain. Unclaimed; MMA has not invited reviews. Period: checked 2026-09-29. Checked 2026-09-29. [marshmma.com Trustpilot profile](https://www.trustpilot.com/review/marshmma.com)
- Trustpilot: TrustScore (Marsh brand) 1.3 (out of 5); 115 reviews. Trustpilot page for marsh.com, the global Marsh brand (mostly individual and non-US customers). This is a different entity from MMA. Period: checked 2026-09-29. Checked 2026-09-29. [Marsh Reviews](https://www.trustpilot.com/review/www.marsh.com)
- BBB: BBB business grade A. BBB San Diego-area profile for Marsh & McLennan Agency LLC (accredited). MMA has separate BBB profiles per office; Dayton and Schaumburg both show A+. Checked 2026-09-29. [Marsh & McLennan Agency LLC (San Diego) BBB](https://www.bbb.org/us/ca/san-diego/profile/insurance-services-office/marsh-mclennan-agency-llc-1126-3000103)
- BBB: Complaints 4. Same San Diego-area profile; zero customer reviews. No client-count denominator. Period: closed in the last three years (checked 2026-09-29). Checked 2026-09-29. [Marsh & McLennan Agency LLC — BBB Complaints](https://www.bbb.org/us/ca/san-diego/profile/insurance-services-office/marsh-mclennan-agency-llc-1126-3000103/complaints); [Marsh & McLennan Agency LLC — BBB Reviews](https://www.bbb.org/us/ca/san-diego/profile/insurance-services-office/marsh-mclennan-agency-llc-1126-3000103/customer-reviews)

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

## Agent and Developer Resources

- [Markdown page](https://spot.insure/compare/aon-vs-marsh-mclennan-agency/commercial-auto.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)
- [Public page index](https://spot.insure/llms.txt)