Additional Insured vs Additional Named Insured
These two endorsement types appear constantly in commercial leases and vendor contracts — and they're routinely confused, sometimes by the people demanding them. Getting the wrong one can leave a counterparty unprotected or create unnecessary expense for the policyholder.
Plain-English: Additional Insured (AI) = third party gets limited liability protection for damages arising from your operations or premises. Additional Named Insured (ANI) = third party gets full insured rights, treated essentially as a co-policyholder.
Side-by-side
| Dimension | Additional Insured (AI) | Additional Named Insured (ANI) |
|---|---|---|
| Scope of coverage | Limited. The additional party is covered only for liability arising out of the named insured's operations, premises, or completed work. Their own independent negligence isn't covered. |
Full. The additional party has the same rights as the original named insured — independent acts, premises, operations. Treated as a co-policyholder. |
| Who typically asks for it | Landlords, project owners, prime contractors, vendors in commercial leases and standard subcontract templates. The most common type of endorsement in commercial leasing. |
Affiliated entities, parent/subsidiary, joint-venture partners — situations where the third party has its own business operations also covered, not just protection from yours. |
| Carrier willingness | Standard. Most GL carriers add Additional Insureds at no charge, often through automatic/blanket endorsements that cover anyone the named insured is contractually required to add. |
Heavier underwriting review. Adding an ANI is essentially adding a full insured — the carrier wants to know who, why, what exposures, and may add premium. |
| Cost impact | Typically free or nominal. Blanket Additional Insured endorsements are standard on most contractor and lessor GL policies. |
Often increases premium meaningfully because the carrier's exposure expands to a separate entity's full operations. |
| Common contract-language confusion | Often what was actually wanted, even when the contract says "named insured." The landlord usually just wants protection from the tenant's liability — Additional Insured does this. |
Rarely what was intended unless there's a true co-business relationship. When a contract demands ANI for a landlord-tenant scenario, push back — the landlord almost certainly meant AI. |
| Form number to look for on the COI | ISO CG 20 10 (ongoing operations) and CG 20 37 (completed operations) are the canonical Additional Insured forms. |
Manuscript endorsement, ISO CG 20 11 (Managers or Lessors of Premises), or custom add-on. Less standardized — read the actual endorsement, not just the COI. |
Bottom line
If your contract demands Additional Named Insured, confirm with the requesting party what they actually need. 8 out of 10 times they meant Additional Insured. If they really do mean ANI, expect a premium increase and additional underwriting review.
If your contract demands Additional Insured, this is routine. Your agent issues the endorsement and the COI typically same-day at no charge.
The COI itself is informational only — read the actual endorsement form attached to your policy to confirm coverage scope. See COI Request Playbook.
Related guides
Sources cited
- Additional insured — International Risk Management Institute (IRMI), 2024
- Additional named insured — International Risk Management Institute (IRMI), 2024
- ISO Additional Insured endorsements (CG 20 10, CG 20 37) — ACORD / Insurance Services Office (ISO), 2024