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Industry · Updated Oct 28, 2026

Certificate of insurance

A broker-issued summary of a subcontractor's insurance coverage, limits and dates, required before a sub starts work and often checked again before payment.

Also called: COI · Insurance certificate · ACORD 25

What it is

A certificate of insurance is a one-page summary, usually on the ACORD 25 form, that the insured’s broker or insurer issues to show that a policy exists: the insured, the carrier, the types of coverage (general liability, workers’ compensation, automobile, umbrella), the limits, the policy dates, whether the certificate holder is an additional insured and whether subrogation is waived. It is not the policy and confers no rights by itself, so many contracts also require copies of the endorsements, but it is the evidence everyone works from.

Why it matters

A subcontract typically requires the sub to carry specified coverage, name the general contractor and owner as additional insureds, and keep a current certificate on file. A policy that has lapsed, or a certificate that lacks a required endorsement, leaves the general contractor exposed if something goes wrong on site, which is why many general contractors hold payment until the certificate is in order. Tracking expiry dates across every sub on every job is a chore that usually lives in a spreadsheet and surfaces at payment time.

How Aquifer fits

In contracts and billing, the insurance you require is set by default or per job, certificates are recorded with their policies, limits and endorsements, and you get notice before they expire. Accounts payable raises an insurance-expiring flag on the bill before anyone approves it, and a payment to a sub missing a required certificate is held with the reason shown. On the portal’s compliance page, a vendor sees what you need on file and where they stand, sends the certificate from the page, choosing the project it covers, and it counts once your team has checked it.

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