Also known as: Evidence of insurance · Insurance proof · COI
Documentation that shows a business actually holds the insurance coverage it claims to have.
Proof of insurance is any document that demonstrates active coverage. For businesses, the standard form is the Certificate of Insurance (COI), typically issued on the ACORD 25 form, which lists the carrier, policy numbers, coverage types, limits, and effective dates. Landlords, clients, general contractors, lenders, and government agencies request proof of insurance before signing a lease, awarding a contract, or letting you start work. A certificate is evidence only: it documents coverage but does not itself grant or change it.
The standard proof is a Certificate of Insurance (COI) on the ACORD 25 form, which lists your carrier, policy numbers, coverage types, limits, and effective dates. Some contracts also request copies of specific endorsement pages, such as additional insured or waiver of subrogation.
Once your coverage is bound, a certificate can usually be issued the same day or within 24 to 48 hours. If a contract requires specific endorsements, add time for the carrier to add them before the certificate can reflect them.
Definitions are educational and may be modified by your specific policy language, endorsements, and state rules. For regulatory guidance, refer to the California Department of Insurance or the NAIC.
Last updated: July 2026.