How to add an additional insured to a certificate of insurance

Start with the document that asked for it. The contract, lease, or vendor packet says who must be an additional insured, on which policy, for which operations, and often with which endorsement form. That clause is what your agent matches the policy against, so send it whole rather than a summary.

The agent then answers one question: does the policy already grant this status? ACORD 25 prints the rule at the top of the form: if the certificate holder is an additional insured, "the policy(ies) must have ADDITIONAL INSURED provisions or be endorsed." There are two ways a general liability policy can have those provisions. A blanket endorsement, such as ISO CG 20 33 or CG 20 38, makes anyone you have agreed in writing to add an additional insured automatically. A scheduled endorsement, such as CG 20 10, names each party in a schedule, so each new party needs a new endorsement from the carrier.

With a blanket form on the policy and a signed contract that requires the status, the party already has it under the form's own terms: CG 20 38 reaches anyone you "have agreed in writing" to add, so no new endorsement is needed and the certificate only has to report it, citing the form. With a scheduled form, the carrier issues an endorsement naming the party first. Smart Choice, a market Redoubt places through, described the order: if it needs an endorsement, the endorsement is done before the certificate is changed.

The wording should say who is an additional insured, on which policy, and under which endorsement, by form number and edition, and nothing the endorsement does not say. We found no regulator-published sample wording, so the lines below are our own illustrations of that shape, not approved text. Referring to the endorsement matters most with a blanket form, because the party's name appears nowhere on the policy; the endorsement number is what ties the name on the certificate to the grant. With a scheduled form, the party is named on the endorsement itself.

The certificate holder is the person or organization the certificate is addressed to, the intended recipient who asked for proof of your insurance, such as a general contractor, landlord, lender, or customer. Being the holder gives them a copy of the facts, not coverage. ACORD 25 says the certificate "confers no rights upon the certificate holder," and New York's insurance regulator, asked whether "certificate holder" means "additional insured," answered no: an additional insured is a party "added to an insurance policy as an insured by the insurer at the behest of the insured."

This is the difference that decides speed. Smart Choice told us certificate holders do not need to be endorsed and can be added once the policy is bound. An additional insured needs an endorsement, either already on the policy as a blanket form or issued by the carrier. If a request only says "list us as certificate holder," ask your agent whether it can go out today; if it says "additional insured," check the policy first.

A holder that reads the endorsement, not just the box, can find mismatches the certificate does not show: a scheduled endorsement that names a different entity, or a form that ends too early. ISO's blanket CG 20 33 and CG 20 38 cover ongoing operations only; under CG 20 33, status "ends when your operations for that additional insured are completed." Completed operations sit on a separate form, such as scheduled CG 20 37, which covers "your work" in the "products-completed operations hazard" for the party it names. A contract that asks for both needs both on the policy.

Coverage under these forms is also capped by the contract: the blanket forms say the insurance "will not be broader than that which you are required by the contract or agreement to provide." That protects you, but it means the contract and the endorsement must line up. When a holder rejects the certificate, ask for the reason in writing and send it to your agent with the contract clause.