Additional insured endorsements explained for contractors
An additional insured endorsement adds another party, usually the owner or general contractor, to a subcontractor's liability policy for claims arising from that sub's work. Which form is used decides whether coverage lasts only during the job or also after it, who is covered, and how much the policy will pay.
An additional insured endorsement amends the Who Is An Insured section of a commercial general liability policy so that a named outside party, such as the project owner or the GC, is covered for certain claims caused by the policyholder's work. In construction, the sub buys the policy and the parties above it in the contract chain ride on it. If a drywall sub's crew leaves a cord across a corridor and a tenant's employee trips, the GC sued by that employee can tender the claim to the drywall sub's carrier.
The details live in the endorsement wording, not on the certificate of insurance. The standard ACORD 25 certificate states that if the holder is an additional insured, the policy must be endorsed, and that a statement on the certificate does not confer rights in place of the endorsement.
The common ISO forms contractors see
Most commercial GL policies use forms written by Insurance Services Office (ISO). Each form number ends with an edition date, such as 04 13 for April 2013. Carriers also write their own versions, so read whatever is attached rather than assuming.
| Form | Title on the form | What it does |
|---|---|---|
| CG 20 10 | Additional Insured: Owners, Lessees or Contractors, Scheduled Person or Organization | Covers the scheduled party for liability caused by your ongoing operations at the listed location |
| CG 20 37 | Additional Insured: Owners, Lessees or Contractors, Completed Operations | Covers the scheduled party for bodily injury or property damage caused by your work in the products-completed operations hazard |
| CG 20 38 | Automatic Status for Other Parties When Required in Written Construction Agreement | Adds anyone you agreed in writing to add, plus parties above them in the chain the contract requires, for ongoing operations |
| CG 20 01 | Primary and Noncontributory, Other Insurance Condition | Makes your policy pay first without seeking contribution from the additional insured's own policy, when conditions are met |
| CG 24 04 | Waiver of Transfer of Rights of Recovery Against Others to Us | Your carrier gives up the right to recover its payments from the scheduled party |
Ongoing operations vs completed operations
This is the distinction that matters most. The CG 20 10 (04 13) covers claims arising during the sub's ongoing operations. It excludes bodily injury or property damage occurring after all work on the project is completed, or after the portion of work that caused the injury has been put to its intended use by someone other than another contractor on the same project. Once the building is turned over, that endorsement stops helping.
Construction defect and water intrusion claims often arrive months or years after turnover. Those fall under the completed operations hazard, which is why contracts pair the CG 20 10 with a CG 20 37. Many contracts also require the sub to keep completed operations coverage in force for a set number of years after final completion. That number is a contract term, so check your subcontract agreement.
Scheduled vs automatic (blanket) status
A scheduled form like CG 20 10 lists names and locations in a schedule. If the owner's legal entity or the project address is wrong or missing, coverage can be disputed. An automatic form like CG 20 38 (12 19 edition) instead covers any person or organization the insured agreed in a written contract to add, and it also reaches other parties that contract requires, such as the owner above the GC. The tradeoff: automatic coverage depends on the written contract existing and saying the right thing before the loss.
Limits and scope built into the forms
- Caused in whole or in part. The 04 13 forms cover the additional insured only for liability caused, in whole or in part, by the named insured's acts or omissions (or those acting on its behalf). Claims solely from the GC's own negligence are generally outside.
- No broader than the contract. If the contract requires the coverage, the additional insured gets no more than the contract requires.
- Lesser of two limits. The most the carrier pays for the additional insured is the amount the contract requires or the policy's available limits, whichever is less. The endorsement does not increase the policy limits.
- To the extent permitted by law. Some states restrict how far contracts can shift risk, and the forms defer to that.
- Professional services excluded. The CG 20 38 sample excludes injury arising from architectural, engineering, or surveying services.
How to get the right endorsements in 5 steps
- Read the owner contract first. List every party it requires as additional insured, the forms or equivalent wording, and the completed operations duration.
- Write those requirements into the subcontract. Name forms by number and edition, or require equivalent coverage, and require primary and noncontributory wording if your owner requires it from you. The flow-down clauses guide explains why.
- Request the endorsement pages from the sub's broker with the certificate, not after.
- Compare the forms to the contract. Check form numbers, edition dates, schedules, and whether completed operations is included.
- Track renewals. A new policy year can bring new forms. Re-review at each renewal and log it, as described in how to track subcontractor insurance certificates.
Worked example: a slip claim after turnover
Say a GC builds a $2.4 million retail building. The tile sub's policy carries a CG 20 10 naming the owner and GC, but no completed operations endorsement. Eight months after the store opens, a customer slips on a section of floor tile that the plaintiff claims was installed with the wrong finish. The customer sues the owner and the GC.
The GC tenders to the tile sub's carrier. The carrier points to the CG 20 10 exclusion: the injury occurred after all work on the project was completed. The GC now defends on its own policy, which may raise its loss history and premium. Had the subcontract required a CG 20 37 naming the owner and GC, and had the coordinator checked for it at buyout, the claim would have had somewhere to go. This is an illustration; how any claim resolves depends on the actual policies and state law.
Mistakes to avoid
- Accepting an X in the ADDL INSD box without the endorsement itself.
- Requiring only ongoing operations coverage on work that can fail after turnover.
- Misspelling the owner's legal entity on a scheduled form.
- Forgetting to require the same coverage from lower-tier subcontractors.
- Assuming a carrier's custom form matches the ISO form it replaced.
Related terms and tools
See waiver of subrogation, hold harmless clause, general liability insurance, and what a subcontractor COI should include. Smart Business Automator stores each sub's certificates and endorsement files with expiration alerts through subcontractor compliance automation.
Frequently asked questions
What is the difference between an additional insured and a certificate holder?
A certificate holder simply receives a copy of the certificate. An additional insured has coverage rights under someone else's policy because an endorsement added it. Being a holder alone gives no coverage.
What is the difference between CG 20 10 and CG 20 37?
CG 20 10 covers the additional insured for liability arising during the named insured's ongoing operations. CG 20 37 covers liability arising from completed work in the products-completed operations hazard. Contractors usually need both.
What does primary and noncontributory mean?
Under the ISO CG 20 01 form, the sub's policy pays first and does not seek contribution from the additional insured's own policy, as long as the additional insured is a named insured on that other policy and the parties agreed to it in writing.
Does an additional insured endorsement cover the GC's own negligence?
The common 2013 ISO forms limit coverage to liability caused in whole or in part by the named insured's acts or omissions, and coverage applies only to the extent state law allows. Claims caused solely by the GC are generally outside.
Can I be added as an additional insured automatically?
Yes, if the sub's policy carries an automatic or blanket form such as CG 20 38, which covers parties the sub agreed in a written contract to add. The written agreement must be in place before the loss.
Sources
- Dormitory Authority of the State of New York: Insurance requirements sample (ACORD 25, ISO CG 20 10 04 13, CG 20 37 04 13)
- City of Sierra Madre, CA: Sample insurance for construction contracts (ISO CG 20 38 12 19, CG 20 01 04 13, CG 24 04 05 09)
- New York State Senate: Insurance Law section 502, certificates of insurance
