Certificate of insurance (COI)

A certificate of insurance (COI) is a one-page document, issued by a subcontractor's insurance agent or broker, that summarizes the insurance policies they carry: who insures them, policy numbers, coverage types, limits and the dates each policy is in force. A standard form for liability coverage is the ACORD 25.

A service company asks for a COI before sending a 1099 subcontractor work, as evidence that the sub carries the coverage the company requires.

What a COI shows

A typical ACORD 25, such as the sample form published by the Hawaii State Procurement Office, lists:

• The producer (agent or broker) and the insured (the sub's business name)
• The insurers providing each coverage
• Each type of insurance, such as general liability, automobile liability, umbrella and workers' compensation, with its policy number
• Policy effective and expiration dates
• Limits, such as each occurrence and general aggregate
• The certificate holder, usually the company that asked for it

What a COI does not do

The form says so at the top. The ACORD 25 sample states that it is "issued as a matter of information only and confers no rights upon the certificate holder," and that it does not amend, extend or alter the coverage of the policies. A guide from the Park District Risk Management Agency makes the same point and notes that being named as an additional insured depends on an endorsement to the policy, not on the certificate. Both sources were checked as of October 2026.

What to require, what limits are appropriate and whether a certificate is enough are questions for your insurance agent or a lawyer. This page is not insurance or legal advice.

When to check it

The practical failure is timing. A COI collected at sign-up shows the policy dates as they were that day. Policies expire and get cancelled.

Check = Expiration date on the COI is after the job date, for every coverage you require

Say a sub's general liability policy expires October 31. A job on October 20 passes. A job booked today for November 4 does not, until you have the renewed certificate. Checking once at onboarding passes all of them.

So check it against each job date, not the day you filed it, and diary the expiration dates. For subcontracted work, this belongs in the same step as scheduling. CrewLink's CrewConnect lets you require insurance, among other credentials, and a person whose credential lapses before the job date is not offered. More on that in subcontractor scheduling and subcontractor management software.

A common mistake

Filing the PDF and never looking at it again. The certificate is a snapshot. If you would not send the job without coverage, check the dates when you send the job.

Common questions

What is a certificate of insurance for a subcontractor?

A one-page summary, usually an ACORD 25 for liability coverage, issued by the sub's insurance agent. It lists the insurers, policy numbers, coverage types, limits and policy dates, and names the company that requested it as the certificate holder.

Does a COI prove the subcontractor is covered?

It shows the agent's summary of coverage on the date it was issued. The form itself says it confers no rights on the certificate holder. Policies can lapse or be cancelled afterward, so check the dates against the job and ask your agent if you need more.

How often should I check a sub's COI?

Before every job, against the job date. In practice, record each policy's expiration date and ask for a renewed certificate before it passes.

Does being the certificate holder make me an additional insured?

Not by itself. Additional insured status comes from an endorsement on the sub's policy. Ask your agent what you need.