COI term

Certificate holder vs. additional insured

Certificate holder just means you got a copy — it grants no coverage. Additional insured means you're added to the sub's policy and actually protected.

Key takeaways

Certificate holder = you were mailed a copy. The ACORD 25 says it confers no rights on the holder — zero coverage.
Additional insured = you were added to the sub's policy by endorsement, so their insurer defends and pays for claims from the sub's work.
Proof is the endorsement, not the certificate: CG 20 10 (ongoing operations) and CG 20 37 (completed operations) for general liability.
Ask the sub's agent (the producer on the certificate) for the endorsement copy — not the sub for a fresh certificate.

By the Sealinn team · 5 min read · Updated July 2026 · Written for general contractors

You were handed a certificate of insurance and your company appears on it. But where your name appears decides whether you actually have coverage. The Certificate Holder box and the Additional Insured line look similar and mean completely different things.

The trap: same form, two very different jobs

On an ACORD 25 certificate, your company can show up in two places. One is basically a mailing label. The other is real protection. People treat them as the same thing. They are not.

Certificate holder (the bottom-left box): this only says a copy of the certificate was sent to you. It is an address label. It gives you no rights under the sub's policy.
Additional insured (noted on the coverage lines and backed by an endorsement): this means you were actually added to the sub's policy, so their insurer must defend and pay for claims that arise out of the sub's work.

Why 'certificate holder' grants you nothing

Being the certificate holder just means the sub's agent mailed you a snapshot of their coverage on that day. It does not add you to anything. The ACORD 25 says so, in its own header, before you even read the numbers.

The line on the form that ends the argument

The ACORD 25 states it 'CONFERS NO RIGHTS UPON THE CERTIFICATE HOLDER' and 'does not affirmatively or negatively amend, extend or alter the coverage afforded by the policies below.' So your name in the holder box changes your coverage by exactly zero. It is a receipt, not a contract.

What 'additional insured' actually buys you

Additional insured status is granted by an endorsement — a document the sub's insurer adds to the policy that names you. Once it exists, the sub's general liability insurer treats you as an insured for liability tied to the sub's work. That is the protection you are really after.

For general liability, the standard ISO endorsements are:

CG 20 10 — Additional Insured, Owners, Lessees or Contractors: covers you for the sub's ongoing operations (while the work is happening).
CG 20 37 — the completed-operations version: covers you after the sub finishes, when a problem shows up later. You want both, because construction claims often surface long after the job ends — see CG 20 10 vs CG 20 37.
Primary and non-contributory wording (usually built into the additional-insured endorsement, or added by a CG 20 01): makes the sub's policy pay first, before yours — see primary and non-contributory.

The certificate reports it; the endorsement grants it

A certificate can type 'Additional Insured: Y' in a box and still be wrong, blank, or out of date. The endorsement is the coverage. If all you hold is the certificate, you are trusting a summary of a document you have never seen — so collect the endorsement itself.

And four things it does not buy

Being an additional insured is worth having, and it is worth knowing precisely what it is not, because a GC who believes it is broader than it is stops asking the other questions.

It is not your own policy. You are an insured under theirs, sharing their limits with them and with every other party they have added. If the aggregate is spent, it is spent for you too — which is the whole argument for a per-project aggregate.
It does not cover your sole negligence. The modern forms grant coverage for liability caused in whole or in part by the named insured's work. A claim arising purely from something your own crew did is not what this endorsement is for, and your own general liability is what answers it.
It does not survive the policy's exclusions. You get the policy as written. A residential exclusion, a wrap-up exclusion or a height limitation applies to you exactly as it applies to them — and the endorsement will not mention it.
It does not entitle you to notice of cancellation. Additional-insured status and notice are separate things, granted by separate endorsements. Being on the policy does not mean the carrier writes to you when it ends — that is its own arrangement.

There is also a third box on the certificate worth keeping distinct from these two: the INSURED box, which names the entity whose policy it is. Holder is who was sent the paper, additional insured is who was added to the coverage, and named insured is whose coverage it is in the first place — and if that last one is not the company that signed your subcontract, the other two do not matter.

What to collect before the sub starts

Do not ask the sub for a fresh certificate — a new certificate just re-reports the same summary. Ask the agent (the producer named on the certificate) for a copy of the actual endorsement pages that name your company.

The CG 20 10 endorsement (ongoing operations) showing your company on its schedule.
The CG 20 37 endorsement (completed operations).
Written confirmation the coverage is primary and non-contributory.
The full endorsement PDF — the pages showing the schedule with your name, not another certificate.

Copy-paste to the sub’s agent

Subject: Additional insured endorsement for [Project] — please send a copy

Hi [Agent name],

We're the general contractor on [Project]. [Subcontractor] lists us as an additional insured on the certificate you issued, but before they start work we need the endorsement itself, not just the certificate.

Please send:
- The CG 20 10 additional-insured endorsement (ongoing operations) naming our company
- The CG 20 37 additional-insured endorsement (completed operations)
- Confirmation the coverage is primary and non-contributory

A PDF of the actual endorsement pages is perfect. Thank you,

[Your name]
[Your company]

Where the difference gets caught

In a filing cabinet the two are indistinguishable: both are a certificate with your company's name on it. Sealinn checks the ADDL INSD column against your requirement, so a sub who is only a certificate holder is flagged as one before the crew arrives.

Where this comes from

ACORD — Certificate of Liability Insurance (form 25)
ISO — Additional Insured — Owners, Lessees or Contractors, Ongoing Operations (CG 20 10)

Tell the two apart before the crew arrives.

Sealinn checks additional-insured status against your requirement, so a certificate holder is never filed as though they were covered.

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