Certificates of insurance: the paperwork that decides who pays when it goes wrong

A COI names the certificate holder, lists coverage and endorsements — additional insured status and waivers of subrogation live in the details. What to require from every sub, and how to track expirations.

Before a subcontractor sets foot on site, one document should already be in the job file: their certificate of insurance. The COI is the evidence that the coverage the contract requires actually exists — and as any owner's insurance requirements show, the details matter. A typical public owner's spec, like New York State OGS's, requires contractors to submit certificates of insurance naming the owner as certificate holder, with additional insured endorsements and waivers of subrogation in favor of the additional insureds documented on the certificate or its endorsements — and accepts only original documents.

What a COI review actually checks

• The named insured matches the subcontract: the legal entity on the certificate is the entity you hired.
• Coverages and limits match the contract: general liability, auto, workers' compensation and umbrella at the required limits — per project, per occurrence, aggregate.
• Endorsements exist, not just boxes ticked: additional insured and waiver of subrogation status live on endorsements; the certificate points to them.
• The expiration date is in a system, not in the drawer: a policy that lapses mid-project is uninsured work you don't know about.

COIs are a per-project register, not a folder

Tracked properly, every sub on every job has a current COI, required endorsements on file, and an expiration date that triggers renewal before it lapses — the same discipline as bonding and lien waivers: risk documents tied to the job record. That register, implemented per company around the way each one works, is what an ERP for construction companies runs.