Explainer

What is a certificate of insurance (COI)?

A certificate of insurance is the one-page proof that a business holds specific insurance cover for a specific period. Simple in theory, and one of the most-requested documents in business.

5 min read Updated 1 July 2026

The essentials

A COI is issued by the insurer or their broker. It lists the insured, the policy type, the coverage limits, the effective dates and any parties named as additional insured. It is not the full policy, it's the summary you share to prove cover exists.

The fields on a typical UK COI

FieldWhat it means
Insured nameLegal entity covered
Policy typePublic liability, PI, employers', motor, etc.
Limit of indemnityMaximum insurer will pay per claim / aggregate
Period of insuranceCover start and expiry dates
ExcessAmount the insured pays before cover kicks in
Additional insuredThird parties named on the policy

What to do with a COI when you receive one

File it against the supplier record, capture the expiry date, set a reminder 60 days out and check the limits meet your contract. Credbase does the last three automatically.

Frequently asked questions

Put this into practice today.

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