What does primary and non-contributory mean?

How does “other insurance” normally work?

When two liability policies cover the same claim, each policy’s “other insurance” condition decides how they interact. By default, policies often share a loss on a pro-rata or equal basis—so the general contractor’s insurer could end up paying part of a claim that arose from a subcontractor’s work. Primary and non-contributory language overrides that default for the GC’s benefit.

What do “primary” and “non-contributory” each mean?

• Primary.The subcontractor’s policy responds first—it is not excess over, and does not sit behind, the GC’s policy.
• Non-contributory.The subcontractor’s insurer will not seek contribution from the GC’s insurer, so the GC’s coverage is not pulled in to share the loss.

Combined, the wording ensures that for claims arising from the sub’s work, the sub’s coverage carries the loss first and on its own—up to its limits—before the GC’s policy is ever considered.

Why does it matter for general contractors?

Primary and non-contributory is the third leg of the standard risk-transfer package, alongside additional insured status and a waiver of subrogation. Additional insured status gives the GC access to the sub’s policy; primary and non-contributory wording makes sure that policy actually pays first and doesn’t reach back into the GC’s coverage. Missing this term can mean the GC’s policy quietly shares a loss it should never have touched—raising premiums and eroding limits.

Where does it live, and how is it verified?

The wording is added by endorsement to the subcontractor’s general liability policy, commonly the ISO CG 20 01 (Primary and Noncontributory – Other Insurance Condition). On the ACORD 25, it may appear as a note in the description box rather than a dedicated checkbox, which is why it is easy to overlook. Confirming it generally requires the endorsement or policy.

What does Wardly check?

Wardly scans each certificate of insurance for primary and non-contributory language and checks it against the requirement you define, alongside additional insured and waiver of subrogation. Each subcontractor is reviewed identically, and the certificate is graded A–F so a missing term is obvious at a glance.

Common mistakes

• Requiring additional insured status but forgetting primary and non-contributory, leaving the GC’s policy exposed to sharing the loss.
• Assuming a contract clause is enough—the policy must be endorsed for the wording to bind the insurer.
• Missing the note in the ACORD 25 description box because there is no standalone checkbox for it.
• Not re-checking the term at each renewal.

Automate the whole package

Additional insured, waiver of subrogation, and primary and non-contributory only protect you if all three are actually present on every certificate. Wardly verifies them automatically—for free. Compare it with COIPulse on the comparison hub.

This is general information, not legal or insurance advice.