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 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. 4,5
What Is Directors and Officers Insurance?
D&O insurance can help pay covered defense costs and losses from claims against company leaders over management decisions. If your organization has a board or executives, check whether the company itself is insured and whether legal bills reduce the limit. 7,8,9
Key Differences in D&O Insurance
Employer Segment and Broker Access
Marsh McLennan Agency names its D&O target organizations and describes an application route. Aon discusses D&O for public and private companies without a numeric size cutoff. A smaller business can ask MMA whether it fits the stated segment; an Aon buyer should ask which markets will consider its ownership and governance structure. 3 6
Program Structure and Coverage
Aon explains Side A, B and C and describes insurer-selection analytics. MMA describes D&O coverage and placement, while the carrier form supplies actual terms. Compare entity coverage, securities treatment, limits and defense-cost erosion in the quotes. 3 6
What to Confirm in D&O Insurance Quotes
- Ask MMA which carriers and size criteria apply; ask Aon for the proposed insurer, Side A/B/C limits and exclusions. 3
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 reviewsMarsh McLennan Agency
Review Score
2 rated sources
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.[8][9][1]
Read Marsh McLennan Agency reviewsOffering Details
Aon vs Marsh McLennan Agency: D&O Insurance: documented features by provider
| Criteria | Aon Directors and Officers Liability brokerage and risk-advisory offering | Marsh McLennan Agency directors officers (official overview) |
|---|---|---|
| Role in This Line | Aon markets D&O broking and advisory services, including insurer selection and program design. It does not issue the described coverage or name the carrier for a buyer’s placement. 3Company-reported. Aon’s official global product/capability page. The statement is limited to Aon’s marketing of brokerage or advisory services, not policy issuance. | Marsh McLennan Agency describes arranging directors officers for the audience stated on the cited product page. 6Company-reported. directors officers 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 page does not identify the insurer or the legal producing entity for a specific placement. Ask Aon to identify both for the quoted risk. 3Not found in reviewed sources. Aon’s global product/capability page reviewed 2026-09-30; no buyer quote, binder or policy was reviewed. This does not establish that no insurer or producing entity is available. | Confirm in your quote. |
| Who It’s For | Aon describes D&O services for public and private companies and discusses executives, directors, managers and board members. This is a target-audience description, not an underwriting eligibility schedule. 3Company-reported. Audience stated by Aon on its global capability page; this does not establish a specific applicant’s eligibility or placement availability by U.S. state. | Corporate executives, board members, and their organizations, as described by the source. 6Company-reported. directors officers 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 explains D&O policies generally through Side A individual protection when company indemnity is unavailable, Side B reimbursement when the company indemnifies a director or officer, and Side C entity coverage, with different descriptions for public and private companies. It notes exclusions can apply; an issued policy determines the actual scope. 3Company-reported. Aon’s broker-authored explanation of the insurance line. It does not establish an individual insured’s policy entitlement; the insurer’s form, endorsements and declarations control. | The cited product page describes D&O for alleged wrongful acts by directors or officers, including described defense costs for civil and criminal actions and investigations. Marketing description only; actual coverage, exclusions, conditions, limits, and availability depend on the issued policy and jurisdiction. 6Company-reported. directors officers 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 standard buyer-specific limit, retention or deductible for this placement. Confirm amounts, sublimits and conditions in the quote and issued policy. 3Not publicly disclosed. Aon’s global product/capability page reviewed 2026-09-30; no buyer quote or policy form 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. 6Not publicly disclosed. Only the cited marketing page was reviewed for published limit and retention information; no policy-form entitlement is inferred. |
| Risk Services | Aon says its brokerage and claims teams collaborate on coverage negotiations and describes insurer-selection analytics and a D&O Risk Analyzer. Those are broker services, not an insurer claim decision or guarantee. 3Company-reported. Company-reported brokerage and advisory services. Account-specific service terms are 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. 6Company-reported. directors officers 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. |
Full Comparison
More Aon vs Marsh McLennan Agency Comparisons
Other D&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.
- Directors’ and Officers’ (D&O) Liability Insurance. Aon; D&O audience and coverage explanation, lines 123–160; insurer-selection, brokerage and claims collaboration, analytics and industry specialization, lines 171–189; contact link at top. Accessed 2026-09-30.
Marsh McLennan Agency
- Who We Are. 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.
- Small Business Insurance Solutions. 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.
- Executive and Professional Liability | MMA. Marsh McLennan Agency; Directors and Officers section; claims for alleged wrongful acts and defense costs. Accessed 2026-09-30.
D&O Insurance Guide
- Glossary of Business Insurance Terms. The Hartford; Directors and Officers Liability Insurance; Errors and Omissions Insurance; Employment Practices Liability Insurance. Accessed 2026-09-16.
- The Chubb Primary Directors & Officers and Entity Securities Liability Insurance. Chubb Group of Insurance Companies; hosted by eperils; I.A–C p.1; I.C p.1; I and III.A–B pp.1–2; VI Reporting pp.3–4. Accessed 2026-09-16.
- Private Company Directors and Officers Liability Coverage. Travelers Casualty and Surety Company of America; I.A–C p.1; I.C p.1; Header p.1 and VI.A pp.6–7. Accessed 2026-09-16.
