How to Check a Contractor’s License in California (2026 Guide)

Every year, the California Contractors State License Board processes thousands of consumer complaints against licensed contractors — homeowners who hired someone, signed a contract, and discovered too late that something was wrong. Every one of those situations started with a decision. Most of those homeowners never checked the contractor’s license before they signed.

Learning how to check a contractor’s license in California takes about 90 seconds. The CSLB runs a free public database that shows license status, bond information, workers’ compensation insurance, and complaint history. This guide walks through every step of a CSLB license check, what each field means, and what to do with the information once you have it. You can also check any California contractor license instantly using our lookup tool, which pulls the same CSLB public records and adds verification context.

California requires a license for any construction project valued at $500 or more, including labor and materials. This isn’t advisory — it’s codified in Business and Professions Code Section 7028. Contracting without a license is a misdemeanor.

The license requirement exists because it’s the only mechanism that ties a contractor to a surety bond, workers’ compensation coverage, and a disciplinary record. Without a license check, you have no way to verify any of those protections exist.

Here’s what a license check confirms before you sign anything:

• Active status — the contractor is currently authorized to perform work in California
• Bond on file — a $25,000 surety bond backs the license per BPC Section 7071.6
• Workers’ compensation — either insured or legally exempt
• Complaint and disciplinary history — documented issues filed with the state
• License classification — confirms the contractor is qualified for the type of work you need

Skipping the license check means trusting a business card. The check itself costs nothing, takes less than two minutes, and is the single most effective step a homeowner can take before hiring. If you’re building an ADU, the stakes are even higher — projects routinely exceed $150,000 and involve multiple inspections over months. A failed contractor at that scale can mean six-figure losses. Browse ADU builders in Sacramento, ADU builders in Los Angeles, ADU builders in San Diego, or ADU builders in the SF Bay Area, or ADU builders in Orange County — every builder listed has been CSLB-verified.

The CSLB license check process is straightforward. You need either the contractor’s license number or business name.

Step 1: Go to the CSLB License Check Page

Visit cslb.ca.gov/OnlineServices/CheckLicenseII. This is the CSLB’s official public lookup tool. It’s free. No login or account required.

Step 2: Enter the License Number

Type the contractor’s license number in the “License Number” field. Every California contractor is assigned a unique number when licensed. This number should appear on their business card, contract, and any advertising. If they don’t have a visible license number, that’s a red flag before you even start the search.

Step 3: Review the Results

The CSLB returns a detail page with the contractor’s full record. You’ll see their business name, license status, classification, dates, bond information, workers’ compensation status, and any complaint or disciplinary history. Each of these fields tells you something specific — and each one matters.

If you don’t have the license number, skip to the name search section below.

The CSLB record is data-dense. Here’s what each field actually means for your hiring decision.

License Status: Active, Expired, Suspended, or Revoked

Active means the contractor is authorized to work right now. This is the only status that should appear on any contractor you’re considering.

Expired means the license lapsed — the contractor didn’t renew on time. They cannot legally perform work until they renew.

Suspended means the CSLB took action to temporarily remove the contractor’s authorization. Suspensions typically result from bond lapses, workers’ comp lapses, or disciplinary action.

Revoked means the CSLB permanently pulled the license. This is the most serious status and usually follows documented fraud, abandonment, or repeated violations.

How to Verify a Contractor’s Bond Status

California law requires every licensed contractor to maintain a $25,000 contractor surety bond. The CSLB record shows whether a bond is currently on file. If no bond is listed, the contractor is out of compliance — even if their license shows “Active.” The bond protects homeowners if the contractor violates the terms of the contract. It’s a minimum protection, not a maximum, and $25,000 won’t cover most ADU disputes. But its absence is a disqualifier.

Workers’ Compensation Insurance Status

The CSLB record shows one of two states: insured or exempt.

Insured means the contractor carries workers’ comp insurance through a named carrier. The carrier name and policy expiration date are public record.

Exempt means the contractor has filed an exemption with the state, certifying they have no employees. Sole operators with no W-2 employees are legally allowed to self-exempt per Labor Code Section 3700. This doesn’t mean they lack insurance — it means they’ve certified under penalty of perjury that they work alone. If they hire subcontractors, those subs must carry their own coverage.

Complaint and Disciplinary History

The CSLB lists documented complaints, legal actions, and citations on the contractor’s record. “No complaints on file” means no consumer has filed a formal complaint with the CSLB — or that complaints were resolved, dismissed, or fall under disclosure restrictions. The CSLB doesn’t publish all complaint details publicly; some are restricted by BPC Section 7124.6. A clean record is good. But it’s not proof that zero problems exist — it’s proof that none were formally filed and sustained. Read more about why CSLB hides some contractor complaints.

License Classification

The classification tells you what type of work the contractor is authorized to perform. The most common are:

• Class B — General Building: authorized for structures and residential construction, including ADUs
• Class A — General Engineering: grading, paving, and engineering projects
• Class C — Specialty: specific trades (C-10 Electrical, C-36 Plumbing, C-20 HVAC, etc.)

For ADU construction, you need a Class B license at minimum. A Class C specialty contractor cannot legally act as the general contractor on an ADU build unless the project falls entirely within their specialty classification.

Not every homeowner has the license number upfront. The CSLB allows searching by business name, which returns all contractors matching that name along with their license numbers and statuses.

The name search process:

1. Go to the same CSLB license check page
2. Enter the business name in the “Business Name” field
3. Review the results — CSLB returns matching businesses with license numbers
4. Click any result to see the full license detail record

Name search is less precise than number search. Common business names return dozens of results. If the contractor gave you a business name that doesn’t appear in the CSLB database at all, they may not be licensed. You can also check any California contractor license instantly using our tool, which searches both CSLB and our verified builder directory simultaneously.

If the CSLB check returns anything other than “Active,” stop.

If the license is expired: Do not sign a contract. Do not pay a deposit. An expired license means the contractor is not authorized to perform work. Some contractors let their license lapse accidentally and renew within days. Others let it lapse because they can’t maintain the bond or insurance. Either way, you should not proceed until the license shows Active again — confirmed by your own follow-up check, not their verbal assurance.

If the license is suspended or revoked: Walk away. A suspension or revocation means the CSLB took formal action. The reasons are on the record. Hiring a suspended or revoked contractor exposes you to the same risks as hiring an unlicensed one — with the added risk that this person already has a documented pattern of problems.

If they claim they’re “in the process” of renewing: Ask for the license number and check it yourself weekly. Do not sign anything until the status reads Active. Contractors who need your deposit to fund their license renewal are contractors who shouldn’t be handling your money.

VerifiedADU automatically flags builders whose license status changes. Contractors on our directory who fail verification standards are moved to our removed contractors list with the reason publicly documented.

A clean CSLB record is necessary but not sufficient. These patterns don’t show up on a license check but indicate risk:

• No written contract — California law requires a written contract for any home improvement project over $500 (BPC Section 7159)
• Demands for large upfront payment — California law caps down payments at $1,000 or 10% of the contract price, whichever is less (BPC Section 7159.5)
• Refuses to provide license number — licensed contractors are required to include their license number on contracts, business cards, and advertisements
• Pressures you to skip permits — unpermitted work exposes you to liability and can void your homeowner’s insurance
• No physical business address — P.O. boxes and virtual offices make accountability difficult
• Cash-only payments with no receipts — no paper trail means no recourse

These are the patterns that show up in ADU contractor scams across California. The license check catches the most obvious risks. These red flags catch the rest.

A CSLB license check is a snapshot. It tells you the contractor’s status at the moment you checked. It doesn’t tell you if the license was suspended last month and just reinstated. It doesn’t tell you if the bond lapsed for three weeks before being renewed. It doesn’t alert you if the status changes between when you check and when you sign.

VerifiedADU monitors every listed contractor’s CSLB record every 12 hours. That means:

• License status is checked twice daily — not once at listing time
• Bond lapses are caught within 12 hours, not weeks
• Workers’ comp changes trigger immediate review
• New complaints are flagged the day they appear on the CSLB record
• Any contractor who fails verification standards is removed from the directory and documented on the removed contractors page

The difference is ongoing monitoring vs. a one-time check. Both matter. The one-time check tells you where the contractor stands right now. Ongoing monitoring tells you if that changes. For a project that lasts 3-6 months, both are relevant.