What Is a Certificate of Insurance? A Contractor's Complete Guide

Every contractor gets asked for a certificate of insurance — usually right before a job starts or when pulling a permit. Most contractors know they need one, but fewer understand what the document actually is, what each section means, and — critically — what the COI cannot do that contractors sometimes assume it can.

This guide walks through the ACORD 25 certificate form, explains each section in plain English, covers what California GCs typically require, and explains the most important misconception about COIs: they are evidence of insurance, not the insurance itself.

What a COI Is — and What It Isn't

A certificate of insurance (COI) is a standardized one-page summary of your active insurance policies. The industry-standard form is the ACORD 25 — "ACORD" stands for Association for Cooperative Operations Research and Development, the nonprofit that develops standard insurance forms.

The COI documents:

• Which insurance policies you have active
• Which carriers are providing the coverage
• The policy numbers and coverage periods
• The coverage limits for each policy
• Whether any additional insured endorsements are in place

Walking Through the ACORD 25 Form

Producer Section (Top Left)

This is your insurance broker's information — name, address, phone, email. The producer (broker) is the one who issues the certificate on behalf of the carrier. If you need a COI, you contact your broker, not the carrier directly.

Insured Section

This is your business information — the named insured on the policy. The name here must match the name on your CSLB license and your policies exactly. Mismatches between "Smith Plumbing" and "Smith Plumbing, Inc." can create coverage disputes.

Insurer Section

Lists the insurance companies providing each line of coverage, identified by letter (Insurer A, B, C, etc.). Each insurer is also shown with their NAIC number — a federal ID for insurance carriers that lets you verify they're licensed in California.

General Liability Section

This is the section GCs scrutinize most carefully. It shows:

• Commercial General Liability checkbox — confirms it's a CGL policy, not a lesser form
• Claims-made vs. occurrence checkbox — occurrence is standard for contractors; claims-made is unusual and requires more scrutiny
• Each Occurrence limit — maximum per single claim (typically $1M)
• General Aggregate limit — total for all claims in the policy year (typically $2M)
• Products/Completed Operations Aggregate — coverage for completed work claims (should match the general aggregate, ideally separate)
• Personal and Advertising Injury limit — typically $1M

Auto Liability Section

If you carry commercial auto, it appears here showing the combined single limit (CSL) or split limits. Most GCs require at least $1M CSL. The form also indicates whether coverage is for any auto, owned autos only, hired autos, or non-owned autos.

Workers Compensation / Employers Liability Section

Shows workers comp coverage (statutory — meaning at California's required limits) and the employers liability limits (typically $1M per accident / $1M policy limit / $1M per disease). If you're a sole proprietor with an exclusion, this section will reflect the owner exclusion.

Description of Operations / Additional Insured Box

This is where endorsements and special provisions are noted. If you've added a GC as additional insured with CG 20 10 and CG 20 37, it should appear here. Primary and non-contributory language, waiver of subrogation, and 30-day cancellation notice provisions are also listed here.

Certificate Holder

The entity receiving the certificate — the GC, property owner, or permit office. The certificate holder is not automatically an additional insured just because they're named in this box. Additional insured status requires a separate endorsement.

What California GCs Typically Require on a COI

While requirements vary by GC and project, here's what you'll encounter on most California construction projects:

City and Permit Office Requirements in California

Many California cities require a COI before issuing a building permit. Here's the general pattern:

• San Diego: The city requires contractors to have a valid CSLB license and typically requires proof of workers comp and GL as part of the permit application process.
• Los Angeles: The LA Department of Building and Safety requires contractors registered with the city to maintain minimum GL insurance and file certificates.
• San Francisco: The SF Department of Building Inspection has specific insurance requirements that include naming the City and County of San Francisco as additional insured on GL policies.
• General pattern: Most California jurisdictions follow a similar pattern — minimum $1M GL, workers comp, and in many cases additional insured status for the city or county on projects involving public property or permits.

What Happens When Coverage Lapses

When your insurance policy cancels or lapses — whether for non-payment, mid-term cancellation, or policy expiration — the carrier is required to notify the certificate holders on file. This triggers several immediate consequences:

• The GC receives notice and can immediately remove you from the project
• CSLB monitors insurance status for licensed contractors and can suspend your license for uninsured periods
• Any claims that occur during a lapse period are personally your responsibility — your carrier owes nothing during uninsured periods
• Future coverage applications require you to disclose the lapse, which can increase premiums or make coverage harder to obtain

The Most Common COI Mistakes Contractors Make

After years of working with California contractors, here are the mistakes we see most often:

1. Issuing a COI that lists coverage the policy doesn't have. If your policy doesn't have a primary/non-contributory endorsement, your COI can't say it does. Issuing a fraudulent certificate can be grounds for policy cancellation and creates personal liability.
2. Assuming the certificate holder is automatically an additional insured. The certificate holder box and the additional insured endorsement are different things. Being listed as certificate holder does not grant AI status.
3. Not matching the legal entity name. "Smith Construction" and "Smith Construction LLC" are different legal entities. The GC may require coverage in a specific entity name. Make sure your policy and COI use the correct legal name.
4. Letting policies lapse and using old COIs. A COI from an expired policy is worthless. Some contractors have mistakenly presented outdated COIs. If your carrier audits or a claim arises, the lapse will be discovered and coverage denied.
5. Not reading the subcontract insurance requirements carefully. Many contractors sign contracts with insurance requirements their current policy doesn't meet. Send us the contract before you sign — we'll tell you whether your coverage complies.

How to Get a COI

Getting a COI is straightforward when you have active coverage. Contact your broker with:

• The certificate holder's full legal name and mailing address
• Whether any additional insured endorsements are required and in what form
• Any special language that needs to appear in the description of operations box
• Where to email the completed certificate

We can issue and deliver most COIs electronically within the same business day. For new projects with specific GC requirements we haven't handled before, we first verify the endorsements are in place before issuing the certificate — ensuring what the COI says matches what your policy actually provides.

Frequently Asked Questions