Industry Deep-Dive · 14 min read

Subcontractor Risk Transfer: COIs, Additional Insureds, and Contract Controls

Subcontractor risk transfer is the coordinated use of a written subcontract, indemnity terms, required insurance, additional-insured endorsements, and compliance records to allocate a subcontractor-caused loss. A certificate of insurance is evidence, not coverage: it does not amend the policy or replace the required endorsement. Contractors should verify the contract, endorsement, policy dates, limits, exclusions, and completed-operations treatment before mobilization.

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Reza Azar · Senior Insurance Broker · OnePark Risk

What subcontractor risk transfer means

Risk transfer moves defined obligations to the party performing the work and backs those obligations with insurance where available. The contract creates duties; the policy determines whether insured risk is covered. Indemnity, insurance, and additional-insured status are related but separate. Anti-indemnity statutes and additional-insured rules vary by state: as of 2016, 46 states had construction anti-indemnity statutes, and several of them (Arizona, Colorado, Georgia, Kansas, Montana, and Oregon among the examples) also void additional-insured coverage for the indemnitee's sole negligence (IRMI, Contractual Insurance Requirements and Anti-Indemnity Statutes, 2016). The ISO endorsements answered those statutes in 2013 by limiting the additional insured's coverage "to the extent permitted by law" and to no more than the contract requires (IRMI, 2013 ISO Additional Insured Endorsements), so project-specific wording should be reviewed by qualified counsel rather than copied from another jurisdiction.

COI versus additional-insured endorsement

A certificate summarizes reported insurance on the date issued and confers no rights. The ACORD 25 form says so on its face: it is issued as a matter of information only, confers no rights upon the certificate holder, and does not amend, extend, or alter the coverage afforded by the listed policies (ACORD 25 sample package, City of Riverside); ACORD adds that only an endorsement, rider, or amendment to the policy changes coverage (ACORD, Certificates of Insurance FAQ).
An additional-insured endorsement changes the policy for qualifying parties and only within its wording. The standard ISO owner/upstream-contractor forms are CG 20 10 for ongoing operations and CG 20 37 for completed operations (IRMI, Effective Contractual Risk Transfer in Construction, 2021).
Ongoing-operations and completed-operations status require different endorsements. Since the 2001 editions CG 20 10 excludes injury or damage occurring after the work is completed or put to its intended use (CG 20 10 04 13 sample), and CG 20 37 is the separate form for "your work" included in the products-completed operations hazard (CG 20 37 04 13). ISO's December 2019 filing added automatic completed-operations forms, CG 20 39 and CG 20 40 (SDV, The 2019 ISO Forms).
Primary and noncontributory wording and waiver of subrogation are separate requirements and separate forms: CG 20 01, the Primary and Noncontributory—Other Insurance Condition endorsement introduced in April 2013, applies only where the named insured agreed to those terms in a written contract (IRMI, Primary and Noncontributory, 2018; IRMI, The 2013 Edition of the CGL Policy), and CG 24 04 waives only the insurer's recovery rights against the scheduled party (CG 24 04 05 09; IRMI, Subrogation and the CGL Policy, 2013).
A blanket endorsement still depends on a qualifying written contract executed when the form requires it, and since 2013 the ISO forms pay the additional insured no more than the lesser of the amount the contract requires and the policy limit (IRMI, 2013 ISO Additional Insured Endorsements).

Pre-mobilization compliance checklist

Execute a written subcontract before work begins.
Match GL, auto, workers' compensation, umbrella, and specialty requirements to the work.
Collect the COI and actual endorsements; confirm named insured, carrier, dates, limits, and each endorsement's form number, edition date, and schedule.
Check trade-sensitive exclusions, including residential, roofing, height, subsidence, action-over, and designated-work restrictions.
Confirm ongoing and completed-operations additional-insured status for every required upstream party, and treat a request for "CG 20 10 11 85 or equivalent" as an exception to resolve: that 1985 edition, which covered liability "arising out of your work" with no completed-operations exclusion (CG 20 10 11 85 reproduction), is generally no longer available (IRMI, Additional Insured Endorsements—A Potential Minefield, Part 3).
Calendar expirations and stop noncompliant subcontractors from mobilizing.

Completed operations and record retention

A loss can emerge after turnover, when the policy and certificate current during construction have expired. Completed-operations additional-insured protection for a period after completion exists only while a CG 20 37-type endorsement is attached to each successive policy during that period (IRMI, Questions and Answers on Additional Insured Issues, Part 2), so the subcontract has to say how many years the subcontractor will carry it and the compliance file has to diary each renewal. Preserve subcontracts, change orders, certificates, endorsements, policies when available, and closeout records for the period required by the prime contract and applicable law. Limitation and repose periods vary by state and claim type; this is a records-control issue, not a universal retention prescription.

Coverage coordination and claim tender

After an incident, notify potentially responsive insurers promptly and tender under both contractual indemnity and additional-insured rights. The upstream contractor's own GL may also receive notice. Priority depends on endorsement language, other-insurance provisions, the pleadings, and state law; "primary and noncontributory" does not eliminate the need to coordinate policies, and a follow-form umbrella follows the primary additional-insured grant only to the extent its own terms do not differ (IRMI, Additional Insured Coverage under Excess Policies, 2017).

Common gaps and exclusions

The certificate names the GC, but no endorsement grants status.
The endorsement covers ongoing operations (CG 20 10) but not completed operations (CG 20 37); the ongoing-operations limitation dates from ISO's 1993 revision and became an express exclusion in 2001 (IRMI, Additional Insureds and Completed Operations, 2001).
The subcontract was signed after work began, defeating a written-contract condition.
The subcontractor's operations fall within a designated-work or residential exclusion.
Umbrella follow-form terms do not match the primary policy's additional-insured grant, or primary-and-noncontributory and waiver terms were never carried to the excess layer (IRMI, Additional Insured Coverage under Excess Policies, 2017).
A lower-tier subcontractor was never enrolled in the compliance process.

Underwriting inputs to prepare

Annual subcontracted cost by trade and state
Standard subcontract and insurance exhibit
Sample COI and required endorsement package
Compliance platform, escalation, and exception procedures
Five years of currently valued loss runs
Largest projects, residential/commercial mix, and lower-tier subcontracting

Safety duties remain with the project team

Insurance transfer does not replace hazard control. OSHA's construction resources describe federal construction standards and employer responsibilities (https://www.osha.gov/construction), while the Bureau of Labor Statistics Injuries, Illnesses, and Fatalities program supplies occupational-safety data (https://www.bls.gov/iif/). Use those sources for safety planning; policy compliance and jobsite safety are distinct controls.

Where the answer depends on the edition, the wording, the state, and the contract

Everything above describes the ISO forms. Which edition is attached matters: the 1985 CG 20 10 covered liability "arising out of your work" with no completed-operations exclusion; the 2001 editions split ongoing operations (CG 20 10) from completed operations (CG 20 37); the 2004 editions adopted the "caused, in whole or in part" causation standard; and the 2013 editions added "to the extent permitted by law," "not broader than required by the contract," and lesser-of limits wording, restated again in December 2019 (IRMI, 2013 ISO Additional Insured Endorsements; SDV, The 2019 ISO Forms). Carriers may attach their own equivalents or automatic forms instead, and proprietary additional-insured endorsements often alter the ISO other-insurance condition (IRMI, Primary and Noncontributory, 2018). The project state's anti-indemnity statute can cut back what any endorsement provides, and the 2013 and later forms give the additional insured no more than the contract required, so the subcontract's insurance clause is itself part of the coverage. The issued endorsement, the policy it modifies, the executed contract, and the governing law control; this article cannot predict how any of them will apply to a particular loss.

Is a COI proof that we are an additional insured?

No. The ACORD 25 certificate states that it confers no rights on the holder and does not amend, extend, or alter the listed policies, and ACORD's guidance says only an endorsement, rider, or amendment changes coverage. Confirm status through the applicable endorsement, its edition, its schedule, and its conditions.

Do we need both ongoing and completed-operations endorsements?

Usually, if the contract requires protection during the work and after turnover. On ISO forms CG 20 10 covers ongoing operations only and, since the 2001 editions, excludes injury or damage after the work is completed or put to its intended use; CG 20 37, or an automatic equivalent such as CG 20 39 or CG 20 40, is the completed-operations form. Whether a carrier's own endorsement combines them depends on that form.

What does primary and noncontributory mean?

It asks the subcontractor's coverage to respond before, and without contribution from, the additional insured's own insurance. On ISO forms the wording is CG 20 01, introduced in April 2013, which applies only where the named insured agreed to it in a written contract; the endorsement and other-insurance wording actually attached control.

Can indemnity replace additional-insured coverage?

No. Indemnity is a contractual obligation; additional-insured status is a policy right. Either can fail independently, and enforceability varies by state.

Should an expired COI be deleted after project closeout?

No. Preserve the compliance file because completed-operations claims can arise later. Set retention with counsel based on contracts and applicable state law.

What should happen when a subcontractor is noncompliant?

Use a documented escalation process: identify the deficiency, require correction, restrict mobilization where contractually permitted, and obtain authorized approval for any exception.

Frequently asked questions