Completed operations endorsement: when CG 20 37 matters
A subcontractor finishes a job. Two years later, a water-intrusion claim surfaces. Without the completed operations endorsement, you're not covered. Here's what CG 20 37 does and how to verify it.
Why both endorsements exist
A typical construction project has two distinct risk windows:
- Ongoing operations— while the work is actively being performed. A worker drops a tool. A vehicle damages a parked car. A subcontractor's scaffolding collapses. CG 20 10 covers the additional insured during this window.
- Completed operations — after the job is finished. The roof leaks. The electrical fails. A weld breaks two years later. CG 20 37 covers the additional insured for these claims.
Most contracts require both endorsements because most projects have both kinds of risk. Skipping completed operations is the easier mistake to make because it doesn't look like a gap until something goes wrong years later.
Verifying it on a COI
On the Acord 25, look in the "Description of Operations / Locations / Vehicles" box for explicit language like:
[Your firm name] is named as additional insured for ongoing and completed operations on the General Liability policy per CG 20 10 and CG 20 37 where required by written contract.
What to verify:
- Both CG 20 10 and CG 20 37 are referenced.
- The endorsements are linked to the active GL policy (not a different line of coverage).
- For high-stakes work, request a copy of both endorsements directly from the broker.
Don't miss CG 20 37 at scale.
COIverify automatically detects when only CG 20 10 is referenced and flags certs that are missing the completed-operations endorsement.
The common mistake
Vendors send a COI with the line "additional insured per CG 20 10" — looks fine, has an endorsement reference, easy to approve. The clerk approves it. The job finishes. Eighteen months later, a defect-related claim surfaces. The vendor's insurer denies coverage to the GC because the cert only listed CG 20 10, and the claim is in the completed-operations window that requires CG 20 37.
The pattern repeats often enough that catching it is a measurable line of defense. If your contract template requires both endorsements, your verification process needs to fail any cert that only references one.
Frequently asked questions
What is a completed operations endorsement?
On commercial general liability, the completed operations endorsement (typically CG 20 37) extends additional-insured coverage to losses arising out of the named insured's completed work — meaning losses that occur after the work is finished, not during it.
Why does it matter if I already have CG 20 10?
CG 20 10 covers ongoing operations only — losses that occur while the work is being performed. Construction-defect claims often surface months or years after work is complete (think water intrusion from a roof installed two years ago). Without CG 20 37, you have no coverage for those late-emerging claims.
How long does completed operations coverage last?
It lasts as long as the underlying CGL policy is in force and the additional-insured endorsement remains attached. Many states have statutes of repose that limit construction-defect claims to a window (often 6–10 years), so coverage during that window is the practical concern.
Related reading
Additional insured: what it means and how to verify it
Adding another party to a policy so they're covered too — and the language to look for to confirm it's actually been done.
ReadAcord 25 form: a field-by-field guide
The standard certificate-of-liability format used across the US. Every field, what it means, and what to look for when verifying.
ReadPrimary and non-contributory: what risk managers need to know
The endorsement that makes the additional insured's coverage primary instead of contributory. Why every general contractor should require it.
Read