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# Certificate of Insurance vs Additional Insured

*Reviewed 2026-05-15*

> These two get confused constantly, and the difference matters. A certificate proves coverage exists. Additional insured status actually extends that coverage to someone else. One is paper, the other is protection.

## Certificate of insurance (COI)

A one-page document that proves your policy exists and shows its coverage types, limits, and dates. It does not change the policy.

## Additional insured

An endorsement that extends your policy's coverage to another party, so they are protected under your policy for covered claims.

## Comparison

| Feature | Certificate of insurance (COI) | Additional insured |
| --- | --- | --- |
| What it is | Proof that a policy exists | An actual extension of coverage to another party |
| Does it change coverage | No, it only summarizes the policy | Yes, it adds a protected party by endorsement |
| Who benefits | Anyone who needs evidence of your insurance | The named party, now covered under your policy |
| How you get it | Requested from your agent, often same day | Added by endorsement, sometimes for a premium |
| Common in | Almost every contract and lease | Contracts where a client or landlord wants direct protection |

## Which is right for you

- Certificate of insurance (COI): A certificate of insurance fits any time you simply need to prove coverage exists. It is fast, free, and required by almost every contract and lease.
- Additional insured: Additional insured status fits when a contract asks a client, landlord, or general contractor to be protected under your policy, not just shown proof of it.

Paper versus protection

A certificate of insurance is a snapshot. It lists your coverage types, limits, and policy dates on one page so a client, landlord, or general contractor can confirm you carry insurance. What it does not do is change a single thing about your policy. The fine print on every certificate says exactly that: it is for information only and confers no rights on the holder.

Additional insured status is different in kind. It is an endorsement that actually adds another party to your policy, so that party is protected under your coverage for claims arising from your work. When a client asks to be named additional insured, they are not asking for a document, they are asking to be covered by your general liability policy when something related to your work goes wrong.

Why the mix-up is expensive

The trap is treating a certificate as if it grants coverage. A contract may require both a certificate and additional insured status, and handing over a certificate alone leaves the other party uncovered, even though the paper looks complete. Confirm what the contract demands: a certificate is almost always required, and additional insured is required whenever the other party wants real protection under your policy. Request a quote or talk to an agent and we will set up both correctly.

## Frequently asked questions

### Does a certificate of insurance give the holder any coverage?

No. A certificate only documents that a policy exists and summarizes its limits and dates. It states on its face that it confers no rights. To extend coverage to another party, you need an additional insured endorsement.

### Is there a charge to add an additional insured?

Sometimes. Some carriers add an additional insured at no cost, others charge a premium or require specific endorsement wording. Certificates are generally issued at no charge. Check with your agent before you commit in a contract.