What Is an Additional Insured Endorsement and Why Do GCs Require It?

If you've ever bid on a subcontract in California, you've almost certainly seen this requirement in the contract: "Subcontractor shall name General Contractor as Additional Insured on its General Liability policy." But what does that actually mean? What does it cost? And how do you get it done quickly so you don't lose the job? Here's a clear explanation.

What Is an Additional Insured?

An additional insured is a person or entity — other than the named insured (you) — who is covered under your insurance policy for certain claims. When a general contractor requires you to add them as an additional insured on your general liability policy, they're asking your insurance company to extend coverage to them for claims that arise from your work on their project.

In practical terms: if a third party sues the general contractor because of something your crew did on the job site, your GL policy would defend the GC and pay any covered damages — not just you.

Why Do General Contractors Require It?

General contractors face significant liability exposure on every project they manage. They're responsible for the actions of every subcontractor on their job site. By requiring all subs to add them as additional insured, GCs ensure that if a sub causes an injury or property damage, the sub's insurance — not the GC's — responds first. It's a standard risk transfer mechanism in the construction industry and is required on virtually every commercial project in California.

What Types of Additional Insured Endorsements Are There?

Most GC contracts in California now require Primary and Non-Contributory additional insured status, meaning your policy must respond before the GC's own coverage. Make sure your policy includes this — not all do by default.

How Much Does an Additional Insured Endorsement Cost?

In most cases, adding an additional insured is included at no extra charge with a standard general liability policy. Some carriers charge a small flat fee ($25–$100 per endorsement) for ongoing and completed operations combined. The certificate of insurance (COI) showing the additional insured can typically be issued the same day you request it.

How Quickly Can You Get a Certificate Showing Additional Insured?

At Asena Capital Insurance Services, we issue certificates of insurance — including additional insured endorsements — the same business day in most cases. If you have a contract requirement, send us the contract language and we'll make sure your certificate matches exactly what the GC is asking for. Call us at (858) 925-9555 or email us and we'll get it done fast.