Insurance and bonds

What is a certificate of insurance in construction?

A certificate of insurance (COI) is a one-page document from an insurance agent that summarizes a contractor's policies, limits, and dates. It shows coverage exists; it does not change or add coverage.

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A certificate of insurance is how one company proves to another that it carries insurance. In construction, owners ask GCs for one, and GCs ask every subcontractor for one before the sub sets foot on site. Most COIs in the U.S. are on the ACORD 25 form, the standard certificate of liability insurance, issued by the contractor's agent or broker.

The certificate lists the insured, the insurers, policy numbers, effective and expiration dates, and limits for general liability insurance, auto, umbrella, and workers compensation. It also names the certificate holder, which is the company that asked for it.

What a COI proves and what it does not

The ACORD 25 carries a printed disclaimer: the certificate is issued as a matter of information only, confers no rights on the holder, and does not amend, extend, or alter the coverage afforded by the policies. That line matters. Checking a box for additional insured on the certificate does not make anyone an additional insured. Only an endorsement on the policy does that.

  • It shows: that policies existed on the date the certificate was issued, with the listed limits and dates.
  • It does not show: exclusions, whether the policy has been cancelled since, or the actual wording of additional insured or waiver of subrogation endorsements.
  • What to ask for with it: copies of the additional insured endorsement and the waiver of subrogation endorsement your subcontract requires.

How COIs work on a real job

Say a GC hires an electrical sub on a $1.1 million medical office build. The subcontract requires $1 million per occurrence and $2 million aggregate general liability, a $5 million umbrella, and the GC and owner as additional insureds on a primary and noncontributory basis. The project coordinator requests a COI with the job name in the description box, compares each limit to the contract, and asks the sub's agent for the endorsements.

Six months in, the sub's GL policy renews. If nobody requests the new certificate, the GC has a sub working on an expired COI. That is the gap most compliance problems come from: not the first certificate, but the renewal nobody tracked.

Common COI mistakes and disputes

  1. Accepting a certificate without reading the limits against the subcontract.
  2. Treating the additional insured checkbox as proof of coverage instead of asking for the endorsement.
  3. Not tracking expiration dates, so renewals lapse mid-job.
  4. Letting the sub's lower-tier subs work without their own certificates.
  5. Paying a sub while its certificate is expired, which can leave the GC's own policy picking up the claim.

Related terms

See insurance certificate tracking, subcontractor prequalification, and hold harmless clause. The guide on what a subcontractor COI should include goes line by line. Smart Business Automator tracks each sub's COI dates and flags expirations before the next payment goes out.

Frequently asked questions

Who issues a certificate of insurance?

The contractor's insurance agent or broker issues it, not the contractor. A COI filled out by the insured itself should not be accepted.

Does being a certificate holder give me coverage?

No. A certificate holder only receives information. Coverage for another party comes from an additional insured endorsement on the policy itself.

How often should a GC collect a new COI?

At least at every policy renewal, and for each new project if the certificate names a specific job. Many GCs also request one at subcontract signing.

What is ACORD 25?

ACORD 25 is the standard certificate of liability insurance form used across the U.S. It summarizes general liability, auto, umbrella, and workers compensation coverage.

Sources

  1. International Risk Management Institute (riskeducation.org): Certificates of insurance seminar materials
  2. AIA Contract Documents: G715 Supplemental Attachment for ACORD Certificate of Insurance 25 (G-Series list)
Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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