A certificate of insurance, also referred to as a COI, is essentially a one page summary that describes your current insurance status. This document identifies the carriers, policy numbers, coverage types, limits, and effective dates. A Certificate of Insurance will provide confirmation that there was coverage in place at the time it was issued. Certificates of Insurance should be provided prior to any new business being conducted with a landlord, general contractor, or client. The purpose of this document is informational only. Therefore, a Certificate of Insurance has no effect upon your actual policy or the creation of coverage. By itself, a Certificate of Insurance does not make the certificate holder an additional insured party.
Most people who ask for a COI assume the paper in their file means they're protected. It often doesn't. The gap between a certificate holder and an additional insured drives a steady stream of errors and omissions claims against issuing agencies, and holders usually discover the problem at claim time.
Certificate of Insurance (COI)
A one-page document summarizing a business's insurance policies, issued as evidence that coverage existed on the date it was produced. Most liability certificates use the ACORD 25, a standardized industry form.
What is a certificate of insurance (COI)?
A certificate of insurance is a standardized summary that your insurance agent or broker issues to a third party, called the certificate holder, who wants proof you carry insurance. For liability coverage, nearly every certificate is issued on the ACORD 25 form, which lists each insurer, the policy numbers and dates, the limits, a description of operations, and the holder's name and address.
A sample certificate of insurance reads top to bottom in fixed blocks: the producer (your agency), the insured business, the insurers lettered A through F with their NAIC numbers, the coverage grid with each policy's limits and dates, the description of operations, and the certificate holder box. The insurer blocks carry each carrier's legal name rather than its brand, which is why a certificate stays accurate through a carrier rebrand like Next Insurance becoming ERGO NEXT. The box a compliance desk reads hardest is the description of operations, which carries the project name, contract number, and any additional insured or waiver notations. Cite the endorsement form number behind each notation there, and attach that endorsement to the certificate.
Those NAIC numbers can be used for more than simply identifying the insurance company. Entering one into the Consumer Insurance Search at the National Association of Insurance Commissioners (NAIC) will provide a complaint index, which measures its share of complaints against its share of premium. A complaint index of 1.0 would indicate that the insurance company has an average number of complaints compared to other insurance companies of similar size, while a number significantly higher than this is worth a question before you rely on the certificate.[3]
When do you need a certificate of insurance?
At any point prior to doing business with another entity or person when there is a request for documentation to verify the existence of an active insurance policy. Some of the most common events or conditions that trigger requests include:
| Who is requesting this documentation from you? | Their reasons for needing this documentation | What they typically require |
|---|---|---|
| Landlord | Tenant negligence at the leased premises | GL certificate, often with additional insured status |
| General contractor | Claims arising from a subcontractor's work | GL and workers comp certificates, additional insured, waiver of subrogation |
| Project owner | Vicarious liability for the contractor's operations | Certificates plus additional insured endorsements down the chain |
| Enterprise client | Contract compliance before onboarding | Certificates showing the minimum limits named in the contract |
| Equipment lessor | Damage its equipment causes in your hands | The certificate shows that an "additional insured" has been added to the Lessee's CGL (Commercial General Liability) policy. |
A typical construction contract asks for $1,000,000 per occurrence and $2,000,000 general aggregate, the default limits on most ISO CGL declarations, so the requirement rarely means buying more coverage. A certificate of insurance for contractors flows both directions: collect one from every sub and vendor, because an uninsured sub's injured employee can make you the statutory employer under workers compensation law, leaving your own policy to pay.
Does a certificate of insurance make someone an additional insured?
No, and this is where real money gets lost. Under the standard ISO CGL policy, only an endorsement can grant additional insured status, and the certificate merely reports what the policy says. For a landlord or general contractor to actually get that status, three things must line up: the contract requires it, the policy is endorsed with a scheduled or blanket additional insured endorsement, and the certificate then reflects it.
On construction work the endorsement question splits in two. CG 20 10 covers the additional insured for ongoing operations, and CG 20 37 covers the products-completed operations hazard after the work is done. Most sophisticated construction contracts require both, and a certificate referencing only one does not satisfy them. Owners often require the CG 20 37 to stay in force for two or three years after completion, since defect claims surface late. When your contract entitles you to that status, ask for the endorsement itself, not just the certificate.
What else do contracts ask for alongside a COI?
A certificate request usually sits atop a bundle of contractual insurance requirements:
- Additional insured status: same as above, requires endorsement.
- Waiver of subrogation: the insured's carrier agrees not to recover a paid loss from the other party. The workers comp policy needs the WC 00 03 13 endorsement, and some states prohibit it.
- Primary and noncontributory: This means that the Named Insured's policy will pay claims without seeking contribution from the Additional Insured's own insurance. Requires the CG 20 01 endorsement on the ISO CGL (Commercial General Liability).
- Notice of cancellation: contracts demand "30 days notice to the certificate holder," which the certificate cannot deliver. The current ACORD 25 (2016/03 edition) states only that notice will be given per the policy provisions.[1] Holder notice exists only if a cancellation endorsement grants it.
Each item is a policy matter your agent cannot bind by typing it on a certificate, and many states now bar certificates that try to amend the policy at all. Texas Insurance Code Chapter 1811, for example, prohibits issuing a certificate that alters, amends, or extends the referenced policy, with civil penalties of up to $1,000 per infraction.[2] When reviewing a sub's COI, confirm the policy period covers your project dates and, for claims-made lines, that you understand the trigger.
Frequently asked questions
What does COI mean in insurance?
COI stands for certificate of insurance, a one-page summary of a company's policies and proof of coverage on the date it was issued. For liability the industry standard is the ACORD 25, listing each carrier with policy numbers, limits, and dates.
Does being listed as a certificate holder give me any coverage?
No. A certificate holder simply receives the certificate. To have rights as stated in the policy (i.e., to receive defense and indemnification) you must be an Insured. As an example, as a Third Party this would require an Additional Insured Endorsement, typically, the CG 20 10 attached to the policy itself.
How long is a certificate of insurance valid?
A certificate is evidence of coverage as of its issue date, for the policy periods it lists. It does not guarantee the policies stay in force, and coverage can be canceled mid-term. The current ACORD 25 promises no cancellation notice beyond what the policy requires, which is why holders demand a fresh certificate at each renewal.
This guide is for educational purposes and summarizes standard ISO policy language. Your policy's specific terms, conditions, and endorsements control. Talk to a licensed broker about your actual exposures.
The Bottom Line
A certificate of insurance is a one-page snapshot that proves your policies existed on the day it was issued, and little more. It does not add coverage, grant additional insured status, or force your carrier to warn a holder before canceling. Only an endorsement does that. Before you rely on anyone's COI, ask for the endorsement behind it and read it against your contract.
References
- 1.ACORD. “ACORD Forms.” Accessed July 2026. https://www.acord.org/forms-search ↩
- 2.Texas Legislature. “Insurance Code Chapter 1811: Certificates of Property and Casualty Insurance.” Accessed July 2026. https://statutes.capitol.texas.gov/Docs/IN/htm/IN.1811.htm ↩
- 3.NAIC. “How to File a Complaint and Research Complaints Against Insurance Carriers.” Accessed July 2026. https://content.naic.org/article/how-file-complaint-and-research-complaints-against-insurance-carriers ↩