A certificate of insurance, or COI, lists the policies a business carries, such as general liability, auto, workers' compensation, and umbrella coverage, along with limits and effective dates. General contractors and owners request COIs from subcontractors, often requiring them to be named as additional insureds.
COIs expire with the underlying policies, so contractors must track expiration dates and request updated certificates on renewal. A lapsed COI can stop work on site or delay payment. Tracking COIs per job and per vendor is a common office automation target.