AIG vs 
Liberty Mutual: How Do They Compare for Umbrella and Excess Liability Insurance?
What Is AIG?
AIG is the marketing name for American International Group, Inc.; AIG says its insurance products are written or provided by subsidiaries or affiliates. Its U.S. business pages list commercial casualty, property, cyber, management and professional liability, and specialty programs, but a brand-level page does not identify the insurer for a particular policy. 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 Umbrella and Excess Liability Insurance?
Umbrella or excess insurance adds liability limits above the policies named in the quote after a covered claim exhausts their limits. It may fit if a contract sets higher limits; check which primary policies are listed and any gaps between them. 7,8,9,10,11
Key Differences in Umbrella and Excess Liability Insurance
Named tower positions versus catalogue listing
AIG markets lead umbrella, mid-excess, and high-excess positions. Liberty Mutual lists umbrella and excess liability in its commercial catalogue and wholesale-industry list. AIG’s description names tower roles, while Liberty Mutual’s reviewed listing establishes line availability in those channels, not a particular layer. Ask Liberty Mutual what placement it can offer your industry. 3 5
Terms and distribution
Liberty Mutual distributes commercial products through brokers and agents; its reviewed umbrella listing does not establish limits or attachment terms. AIG says its placements may integrate with other casualty lines and sets underlying policies and attachment points for the account. Ask either route for the full schedule, including insurer, limits, and follow-form terms. 3 5
What to Confirm in Umbrella and Excess Liability 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.
AIG
Review Score
2 rated sources
Customer ratings for AIG are low: Trustpilot shows 1.9 out of 5 from 252 reviews, and NerdWallet gives 2.5 stars and notes more claims complaints than expected. These pages cover many AIG products and countries, so they only loosely describe business insurance.[1][2]
Read AIG 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
AIG vs Liberty Mutual: Umbrella and Excess Liability Insurance: documented features by provider
| Criteria | AIG Excess Casualty and Lead Umbrella | Umbrella and Excess Liability |
|---|---|---|
| Role in This Line | AIG markets admitted and non-admitted excess casualty capacity, including lead umbrella, mid-excess and high-excess positions. The legal insurer and structure for a specific tower are account-specific. 3Company-reported. Role in this product is limited to the description on the linked AIG source. | Liberty Mutual lists umbrella and excess liability in its commercial catalogue and in a wholesale-industry coverage list. 5,6Company-reported. Official Liberty Mutual commercial/product page; company-reported description scoped to Umbrella and Excess Liability. Not policy wording, underwriting approval, state eligibility or a coverage guarantee. |
| Who It’s For | AIG describes lead umbrella, mid-excess and high-excess placements for a wide range of accounts, including small-business and corporate risks. It does not state an account-specific appetite or attachment eligibility. 3Company-reported. Audience is the segment AIG names on the linked source; this is not an underwriting decision, quote or guarantee of availability. | The commercial business pages distribute products through brokers and agents. 5,6Company-reported. Official Liberty Mutual commercial/product page; company-reported description scoped to Umbrella and Excess Liability. Not policy wording, underwriting approval, state eligibility or a coverage guarantee. |
| Coverage Features | AIG describes excess liability protection against severe liabilities and lead umbrella placements that may integrate with other casualty lines. The exact underlying policies, attachment points and follow-form terms depend on the placement. 3Company-reported. AIG’s public product description is not the policy. Actual entitlement depends on the applicable issued form, endorsements and declarations. | Its wholesale page names umbrella/excess cover as an option for that industry; limits and attachment terms are not established here. 5,6Company-reported. Official Liberty Mutual commercial/product page; company-reported description scoped to Umbrella and Excess Liability. Not policy wording, underwriting approval, state eligibility or a coverage guarantee. |
| Limits and Retentions | AIG advertises up to $75 million total capacity on an individual-account basis, subject to underwriting. This is not a standard or guaranteed limit for a buyer. 3Not publicly disclosed. This statement reports only what the linked public source discloses and does not substitute for a quote or issued policy. | Confirm in your quote. |
| Risk Services | AIG describes in-house risk experts, claims specialists, litigation-management strategies and integration with domestic and foreign casualty platforms. Those services do not change policy wording. 3Company-reported. The linked page describes company-reported support; specific account services and third-party arrangements must be confirmed. | 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. 5,6Not 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 AIG vs Liberty Mutual Comparisons
Other Umbrella and Excess Liability Insurance Comparisons
Sources
AIG
- Investor Relations. American International Group, Inc. (AIG); About AIG and legal footer; lines 244–246 and 327–331. Accessed 2026-09-28.
- Business. AIG US; Surplus Lines heading and paragraph, lines 357–359. Accessed 2026-09-28.
- Excess Casualty Insurance. AIG; Official AIG Excess Casualty page: admitted/non-admitted options, lead umbrella/mid/high excess placements, advertised per-account capacity subject to underwriting, domestic/foreign integration, risk and claims services. 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.
- Wholesale Distribution. Liberty Mutual Business Insurance; Wholesale coverage options list includes cargo stock throughput, commercial auto, cyber, D&O, environmental, general liability, inland marine, management liability, property (including equipment breakdown), trade credit, umbrella/excess and workers compensation. Industry-specific examples, not universal eligibility. Accessed 2026-09-29.
Umbrella and Excess Liability Insurance Guide
- Liability Insurance. Insurance Information Institute; Heading Umbrella Liability Insurance; sentence Umbrella Liability—also known as Excess Liability Insurance; underlying policies listed with limits; typically GL, auto and employers’ liability; starts when a covered loss exhausts the primary per occurrence limit; Most umbrella policies exclude EPL, professional liability, product recall, workers compensation, asbestos, pollution, war and terrorism. Accessed 2026-09-16.
- Commercial Insurance Guide. California Department of Insurance; Commercial Umbrella; excess over a basic liability policy; auto/CGL/WC or any liability policy can be covered; may respond if basic policy not in force or for gaps; SIR when no underlying. Accessed 2026-09-16.
- Lines of Insurance. California Department of Insurance; Umbrella or Excess Liability Policy: excess limits over existing liability; may provide additional coverages not provided by underlying policies. Accessed 2026-09-16.
- Coverage Hub. Coverdash; Excess & Specialty: Umbrella; Excess Liability. Accessed 2026-09-16.
- Products. Kinro; 09 Umbrella/Excess: additional limits above scheduled underlying policies; when to review; reviewed with. Accessed 2026-09-16.
