Certificate of insurance (COI)

A certificate of insurance is a document issued by an insurer or broker summarizing the policies a contractor carries — typically commercial general liability, automobile liability, and umbrella coverage — with limits, deductibles, and expiry dates. RFPs and construction contracts ask for one as proof the required insurance is actually in place before work starts.

What a COI proves — and what it doesn't

A COI is evidence, not the policy itself. It shows that coverage existed and roughly on what terms at the date of issue; it does not amend the policy, and most certificates state that they confer no rights on the holder. That is the trap for buyers: receiving a certificate naming you as "certificate holder" gives you a piece of paper — not coverage under the contractor's policy. If something goes wrong on the site and a claim touches your organization, a certificate alone does not obligate the contractor's insurer to defend or indemnify you.

Certificate holder vs. additional insured

Being a certificate holder means you were sent the certificate as evidence of the contractor's insurance. Being an additional insured means the contractor's policy has been extended so that your organization also has coverage under it for claims connected to the contractor's work. The additional insured status is what protects the owner or buyer when the contractor's operations create liability that touches them — and it is confirmed through the policy endorsement, not merely through a line on the certificate.

CCDC Bulletin 4 ("Additional Insureds", published by the Canadian Construction Documents Committee) is the industry's reference here. It notes that unlike the more standardized additional insured endorsements used in the United States, a variety of clause wordings are used in Canada, so contractors should have their broker review each contract's additional insured requirement against the actual endorsement before signing. The bulletin also flags a common Canadian practice: because formal endorsements cost more to issue, insurers frequently add additional insured wording directly on the certificate of insurance instead — which is precisely why buyers should not treat the certificate wording as proof the endorsement exists.

What buyers and vendors should do

Buyers writing RFP requirements should specify not just policy types and limits but also that the owner/buyer be named additional insured on the CGL (and other required policies where appropriate), and should request copies of the endorsements along with the certificate. Vendors responding should confirm with their broker that the required additional insured wording can actually be endorsed onto their policies before submitting — CCDC's guidance is that if the requirement cannot be met, it should be flagged before the contract is signed, not discovered at claim time.

Common questions

Is a COI the same as proof of WSIB/Clearance?

No. A COI evidences the contractor's own commercial insurance policies (liability, auto, umbrella). A WSIB clearance certificate, in Ontario, evidences that the contractor's workplace insurance account with the Workplace Safety and Insurance Board is in good standing — a different requirement, aimed at workplace injury coverage for workers, not at third-party liability protection for the buyer.

Who pays for additional insured status?

Adding a project owner as additional insured is ordinarily handled within the contractor's existing policy at little or no extra premium, but the wording varies by insurer and by endorsement form — which is exactly why CCDC Bulletin 4 tells contractors to verify the endorsement fully meets the contract requirement. Where extended coverage is genuinely needed, premium adjustments are negotiated between the contractor and its insurer.

Related definitions

Insurance requirements in RFPs · WSIB clearance · Bonded vs. insured · Third-party inspection