Does the certificate of insurance prove you have additional insured coverage?

No. The certificate of insurance is explicitly stamped 'for information only' and 'confers no rights upon the certificate holder.' Only the endorsement form actually amends your policy and creates the coverage. The COI references the endorsement; the endorsement is the coverage.

What is the difference between additional insured and named insured?

You are the named insured on your policy. The GC is added as additional insured for liability arising out of your work only, not for their own independent negligence. Additional insured is a limited extension of coverage, not full policy ownership.

Why do GC compliance teams reject certificates and demand endorsements?

Because the certificate alone proves nothing about actual coverage. GCs request the endorsement form because it is the only document that actually amends your policy. A certificate that lists the GC as additional insured with no endorsement attached evidences nothing.

What is the difference between CG 20 10 and CG 20 37?

CG 20 10 covers ongoing operations and drops off when the job ends. CG 20 37 covers completed operations for work that outlives the project. Many subcontract exhibits demand both endorsements.

What other insurance requirements do GCs typically demand alongside additional insured?

67% of subcontract exhibits also demand primary and non-contributory wording plus waiver of subrogation. Additional insured alone is only one of three asks; verify the full exhibit before signing.

What Additional Insured Actually Means

Additional insured on GC subcontracts: created by endorsement (CG 20 10/37), not certificates. Verify before signing to avoid payment holds.

This content is general information only and is not legal, tax, financial or insurance advice. Speak to an appropriately licensed professional before acting on it.

Last updated: October 2026. Clause mechanics verified October 2026 — the words on the exhibit matter more than the words on the certificate; verify your endorsement before you sign.

Methodology: Built by cross-referencing ISO endorsement forms, state insurance code, and construction contract law.

"Additional insured" on a GC subcontract means your general liability policy is amended by endorsement to extend coverage to the general contractor as if they were insured under your policy, for liability arising out of your work. It is created by an endorsement form (most commonly CG 20 10 for ongoing operations and CG 20 37 for completed operations), not by the certificate of insurance. A certificate that lists the GC as "additional insured" with no endorsement attached evidences nothing. In every one of the 50 states, the clause mechanics are identical; only licensing and workers' comp thresholds change by state.

TL;DR

Additional insured status is created by an endorsement form (CG 20 10 / CG 20 37), not by the COI. The certificate is a snapshot; the endorsement is the contract.
"Additional insured" ≠ "named insured." You are the named insured. The GC is added for liability arising out of your work, not for their own independent negligence.
67% of subcontract exhibits also demand primary and non-contributory wording plus waiver of subrogation. Additional insured alone is only one of three asks.
Completed operations is the trap. CG 20 10 covers ongoing work; it drops off when the job ends. For work that outlives the project, the exhibit wants CG 20 37 too.
Do not sign a subcontract exhibit without attaching the actual endorsement form to your broker — a certificate alone is not proof.

What additional insured actually means on a GC subcontract

Additional insured means your general liability policy has been endorsed to add the general contractor as a party who can tap your coverage when a claim arises out of your scope of work on their project. If your crew's work causes a loss and the GC gets named in the suit, the GC turns to your policy first, under the endorsement, instead of their own.

That is the whole mechanic. It is a transfer of risk down the chain: the party doing the work carries the party managing the site.

The confusion starts because the word shows up in two places that do two different things. It shows up on the certificate of insurance (COI), which is a one-page summary your broker issues. And it shows up on the endorsement, a form physically added to your policy that changes what the policy covers.

Only one of them actually does anything.

Definition — Additional insured (construction subcontract): A party added to a subcontractor's general liability policy, by endorsement, so that the party (typically the GC and often the owner) is covered for liability arising out of the subcontractor's ongoing or completed operations. Created by an ISO endorsement form such as CG 20 10 (ongoing operations) or CG 20 37 (completed operations). Evidenced by the endorsement itself; the certificate of insurance only references it.

Why the certificate does not prove you have it

The certificate of insurance proves nothing about the actual terms of your coverage. The ACORD 25 certificate form carries a disclaimer in its own header: it is issued "as a matter of information only" and "confers no rights upon the certificate holder." It does not amend, extend, or alter the coverage afforded by the policies it references. In plain terms, the COI is a courtesy summary — a photograph of what your broker believes to be true on the day it was issued. It is not the policy, and it is not the endorsement.

When a GC's exhibit says you must name them as additional insured, the only document that satisfies that obligation is the endorsement form attached to your policy. If a dispute reaches a claim, the carrier reads the endorsement, not the certificate. Courts across jurisdictions have repeatedly held that a certificate of insurance, standing alone, does not confer additional insured status when the underlying policy contains no endorsement to that effect.

So before you sign: ask your broker for a copy of the actual CG 20 10 and/or CG 20 37 endorsement, confirm the edition date, and confirm the GC (and owner, if required) is named or described within it. A certificate that lists them in the "Description of Operations" box with no endorsement behind it is a liability you are carrying without the coverage you promised to provide.

External authorities

Insurance Services Office (ISO) — publisher of the CG 20 10 and CG 20 37 standard endorsement forms. Form specifications and edition dates: verisk.com/insurance/products/iso-forms (accessed October 2026).
National Association of Insurance Commissioners (NAIC) — consumer and producer guidance on certificates of insurance and endorsement verification: naic.org (accessed October 2026).
American Bar Association, Forum on Construction Law — practitioner resources on additional insured clauses and risk transfer in subcontracts: americanbar.org/groups/construction_industry (accessed October 2026).

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