Contractor Certificate of Insurance: What Bay Area Homeowners Should Check

What is a certificate of insurance, and why does it matter?

A certificate of insurance, commonly issued on the ACORD 25 form, is a one-page summary of the insurance policies a contractor holds. It lists the carriers, policy numbers, effective dates, coverage types, and limits. For a Bay Area homeowner about to sign a six or seven figure contract, the COI is the single most important document to request before the first payment.

The COI is not a legal substitute for the underlying policy. It is a snapshot issued by an insurance producer that reflects what was true at the moment of issuance. Policies can be canceled, lapsed, or modified the next day. That is why the COI is a starting point, not an ending point, and why the verification steps below matter as much as the checklist items themselves.

Which insurance coverages should a California contractor carry?

California law treats the three major contractor coverages differently. Understanding which are mandatory, which are conditional, and which are industry practice helps you read a COI critically instead of trusting it at face value.

Workers’ compensation. Historically, California required workers’ comp only when a contractor had employees. Senate Bill 216, signed in 2022 (Chapter 978, Statutes of 2022), phased that exemption out. Effective January 1, 2023, four license classes (C-8 Concrete, C-20 HVAC, C-22 Asbestos Abatement, and D-49 Tree Service) lost the sole-proprietor exemption. Effective January 1, 2026, the requirement extends to every CSLB licensee and applicant, with a narrow joint-venture exception under Business and Professions Code Section 7029. In practice, this means every Bay Area homeowner hiring a licensed contractor in 2026 should receive a current workers’ compensation certificate.

Commercial general liability (CGL). CGL is not statutorily required for most individual California contractors. The CSLB’s own guidance notes that contractors building single-family residences for owner-occupants must disclose in writing whether they carry CGL, the carrier’s name, and the coverage amounts. LLC-licensed contractors are separately required to carry at least $1 million in liability coverage (up to $5 million depending on personnel of record). The practical answer: CGL is not a statutory mandate for every contractor, but it is nonnegotiable as a contract condition that a reasonable homeowner should require.

Commercial auto. Required wherever the contractor uses vehicles for the business, including transporting tools, materials, and crews to your site. Ask whether the contractor will operate trucks, trailers, or loaders on the property.

How to read a contractor’s COI line by line

The ACORD 25 form follows a consistent layout. Work through it in this order.

Producer box (upper left). This is the insurance agent or broker who issued the certificate. Record the name, phone number, and email. You will call this person during verification.

Insured box (upper right). The legal name of the contractor. This must match the business name on the contractor’s CSLB license exactly. If the COI lists “ABC Construction LLC” but the CSLB license is issued to “ABC Construction Inc.,” the policy may not extend to your project. Subtle name differences matter.

Insurers affording coverage. Each policy on the certificate is numbered A, B, C, and so on. Confirm each insurer has an acceptable rating. A.M. Best A- or better is the common threshold cited by industry sources.

Coverage rows. This is the heart of the document. Look for:

• Commercial General Liability: each occurrence limit, general aggregate, products and completed operations aggregate. Typical residential-remodel standards cited by industry practice are $1M per occurrence and $2M aggregate. Custom Home Design and Build (CSLB #986048, licensed since 2005) carries $2,000,000 in general liability coverage as our baseline.
• Automobile Liability: combined single limit or split limits. Confirm coverage applies to hired and non-owned vehicles if the contractor uses subcontractor trucks.
• Workers’ Compensation and Employers’ Liability: policy number, effective dates, and the per-accident and per-disease limits. California statutory workers’ comp has no scheduled dollar limit on medical benefits, so focus on verifying the policy is active.
• Umbrella / Excess Liability: optional but common on larger projects.

Description of Operations box. This is where endorsements and project-specific language appear. You want to see the homeowner named as additional insured on the general liability policy, and ideally a waiver of subrogation referenced.

Certificate Holder box (lower left). This is the party to whom the certificate is issued, usually the homeowner. Confirm your name and project address are correct. A COI issued to a lender or a prior customer does not protect you.

What is an additional insured endorsement, and why should it name you?

An additional insured endorsement extends the contractor’s general liability policy to cover a named third party (you) for liability arising from the contractor’s work on your project. It is usually documented through an ISO form such as CG 20 10 (ongoing operations) or CG 20 37 (completed operations), and it is summarized on the COI in the Description of Operations section.

Why it matters: without the endorsement, if a neighbor, a guest, or a delivery driver is injured on your property during construction and sues, you may be defending the claim out of pocket even though the contractor’s carrier is the one with deep coverage. With the endorsement, the contractor’s insurer has a contractual duty to defend and indemnify you for qualifying claims.

Always ask for both ongoing-operations and completed-operations additional-insured language. Ongoing operations covers you during the build; completed operations covers you after the project is finished, which is when latent-defect claims typically surface.

How do I verify the COI is real and still active?

Three verification steps, in order.

1. Check the CSLB license first. Use the Check a License tool to confirm the contractor is licensed, classifications are appropriate for your project, bond is posted, and workers’ comp is listed as active (not exempt) on or after January 1, 2026. See our CSLB license verification guide for a detailed walkthrough.
2. Call the producer listed on the COI. Introduce yourself as the certificate holder on a project and ask them to confirm (a) the policies are in force today, (b) the limits match what is on the certificate, (c) the additional insured endorsement has been issued, and (d) your project address is included.
3. Require a 30-day notice of cancellation clause. Ask the contractor to have the producer issue a revised COI if any policy changes during the project. Policies can be canceled mid-project for non-payment or loss experience, and you want to know when that happens.

Red flags on a contractor’s certificate of insurance

Certain patterns on a COI should stop a contract signing until resolved.

• Named insured does not match the CSLB license. Different legal entity, different policy.
• “Workers’ comp exempt” status shown on CSLB in 2026. Under SB 216 Phase 2, this should no longer appear for licensed contractors outside the narrow joint-venture exception.
• Policies expiring before your project end date. Ask for a renewal certificate before work begins.
• No additional insured endorsement. Pre-printed forms often omit this; a compliant contractor will have their producer issue a project-specific certificate.
• Coverage limits below what your contract requires. The contract controls; the COI must match or exceed.
• Refusal to let you call the producer. A contractor who resists direct verification is signaling something.
• Handwritten modifications on the COI. Valid certificates are issued electronically by the producer; handwritten changes are not trustworthy.

What happens if an uninsured contractor’s worker is hurt on my property?

This is the catastrophic-risk scenario SB 216 was designed to address. If a contractor without workers’ compensation has a worker injured on your property, the worker can file a personal-injury claim against the homeowner. Your homeowner’s insurance may deny the claim because construction exposure is typically excluded. The result, in a serious-injury case, can be a six or seven figure personal exposure.

This is the single strongest reason to insist on a current workers’ comp certificate from every contractor who sends workers to your property, including subcontractors. General contractors’ policies do not automatically cover subcontractors’ employees. For large projects, ask for sub-level COIs during construction, not just at the start.

Is the CSLB contractor bond insurance?

No. The CSLB contractor license bond is a $25,000 surety bond (increased from $15,000 on January 1, 2023 under SB 607). It compensates consumers for specific statutory violations, compensates employees for unpaid wages, and compensates subcontractors and suppliers for unpaid work. It pays out from the contractor’s future assets after a claim is adjudicated, not from an insurance carrier’s reserves. It is complementary to, not a substitute for, general liability and workers’ compensation insurance.

For context on how the bond fits into a broader payment-protection plan, see our guide to mechanics liens in California.

Your pre-hire insurance verification checklist

Before signing a Bay Area home-improvement or custom-home contract, confirm each of the following.

• CSLB license is active, classifications match the project, and workers’ comp is listed as active on the CSLB public record.
• Certificate holder box names you and the project address correctly.
• Named insured matches the CSLB-licensed business name exactly.
• Workers’ compensation policy is in force and covers every trade category that will be on site.
• General liability meets your contract minimum (commonly $1M per occurrence, $2M aggregate for residential; $2M+ per occurrence for larger custom-home work).
• Commercial auto covers vehicles operating on the property.
• Additional insured endorsement names you on both ongoing and completed operations.
• Insurers are A.M. Best A- or better.
• You called the producer to confirm all of the above in writing via email follow-up.
• Deposit request complies with California Business and Professions Code Section 7159.5 (lesser of $1,000 or 10% of contract price).
• Contract is written and signed before any work starts, with any changes documented under the written change-order rules.

Insurance premiums are not a fixed line item

Contractor insurance premiums vary by trade mix, project type, claim history, and coverage limits. Do not treat a low insurance cost as a competitive advantage or a high cost as a warning sign. What matters for the homeowner is the adequacy of coverage and the verifiable status of the policy on the day work begins, not what the contractor pays for it.

This guide is educational, not legal or insurance advice. For project-specific coverage questions, consult a licensed California insurance broker. For contract-specific questions, consult a California attorney experienced in residential construction.

Talk with a licensed Bay Area design-build team

Custom Home Design and Build has served 60+ Bay Area cities since 2005 under CSLB #986048. We carry $2,000,000 in general liability and $3,000,000 in workers’ compensation coverage, and we issue a project-specific COI naming every client as additional insured before construction begins.

Contact Custom Home for a free consultation to walk through your project scope and receive a documentation package that meets the full pre-hire checklist above.