How to File a CSLB Complaint in California

Between 2020 and 2024, the California Contractors State License Board closed over 10,700 complaints without investigation. Most homeowners who file a CSLB complaint expect the Board to fix their project or force the contractor to return their money. It does neither. The CSLB is a licensing authority, not a court. It can pull a contractor’s license. It can issue fines. It can refer cases for criminal prosecution. But it cannot write you a check or order your walls finished.

That gap between what people expect and what the CSLB actually does is where homeowners lose time, lose ground, and sometimes lose their window to recover money through other channels. This guide covers the full CSLB complaint process — what to file, when to file it, and what else you should be doing at the same time.

This is part of our ongoing ADU contractor scam investigation series.

Not every bad contractor experience is a CSLB issue. If you disagree about tile color or the finish on your cabinets, that’s a contract dispute — handle it through mediation or small claims court.

A CSLB complaint is the right move when a contractor:

• Collected a deposit exceeding the legal limit under BPC §7159.5
• Abandoned the project without finishing the contracted work
• Performed work without a valid CSLB license
• Failed to pull required building permits
• Diverted project funds (took your money but didn’t pay subcontractors or suppliers)
• Made material misrepresentations about their qualifications or license status
• Willfully departed from plans or specifications without authorization

These are license violations — the specific category of misconduct the CSLB has authority to act on.

The California contractors state license board complaint process is administrative, not judicial. Here is the boundary:

The CSLB Can	The CSLB Cannot
Investigate license violations	Force a contractor to finish your project
Suspend or revoke a contractor’s license	Recover your money directly
Issue citations and fines ($200–$15,000)	Mediate quality-of-work disputes
Refer cases to the DA for criminal prosecution	Act as your attorney
Order restitution through formal disciplinary action	Guarantee investigation of every complaint filed

The restitution line is worth noting. In formal disciplinary cases, the CSLB can order a contractor to pay restitution as a condition of keeping their license. But this only happens in cases that go through the full accusation and hearing process — not a quick resolution.

The strength of your complaint depends entirely on your documentation. The CSLB won’t investigate a vague “this contractor was bad” claim. They need specifics.

Document	Why It Matters
Signed contract	Proves scope, price, and terms. No contract = its own violation (BPC §7159)
Payment records	Checks, bank transfers, Zelle/Venmo receipts — proves how much you paid and when
Photos with timestamps	Shows state of work (or lack of it) at specific dates
Written communications	Texts, emails showing promises, excuses, or silence from the contractor
Contractor’s license number	Look it up at cslb.ca.gov if you don’t have it
Timeline of events	Dates of payments, work start, work stop, last contact — builds the narrative

If the contractor was unlicensed, that’s a separate and more serious violation under B&P Code §7028. You can still file a complaint — the CSLB investigates unlicensed activity too.

Before filing, verify the contractor’s license status so you know exactly what you’re dealing with — active, expired, suspended, or revoked.

Online (recommended)

Go to cslb.ca.gov, click “File a Complaint,” and fill out the online form. You can upload supporting documents directly. Takes about 15 minutes. This is the fastest path to getting your complaint into the system.

By mail

Download the complaint form from cslb.ca.gov. Print, fill out, and mail with copies of your evidence (never originals) to CSLB headquarters in Sacramento. Expect 2–4 weeks for processing. Send via certified mail so you have proof of delivery.

By phone

Call (800) 321-CSLB (2752), Monday through Friday, 8 AM to 5 PM Pacific. A representative can walk you through the process and answer questions about what qualifies as a complaint. They cannot file the complaint for you over the phone — you’ll still need to submit documentation.

The CSLB does not move fast. Set expectations accordingly.

Timeframe	What Happens
0–10 days	Complaint received. Acknowledgment letter sent to you.
10–60 days	CSLB reviews complaint. May contact you for additional documentation or clarification.
60–120 days	If investigation opened, an investigator is assigned. Site visit, contractor interview, document review.
120+ days	Investigation findings lead to: citation with fine, formal accusation (hearing before an ALJ), or case closed.

If the CSLB determines a violation occurred, the contractor can face citations with fines up to $15,000, a formal accusation leading to a hearing before an Administrative Law Judge, license suspension or revocation, or referral to the local District Attorney for criminal prosecution.

Most investigations resolve in 3–6 months. Cases with multiple complainants — like Nonna Homes (23 complaints) or Anchored Tiny Homes (450+ affected homeowners) — can take a year or more.

Don’t wait for the CSLB to finish before pursuing your own legal options. Start civil court proceedings in parallel.

A CSLB complaint addresses the contractor’s license. It does not put money back in your account. For financial recovery, you need one or more of these:

• Small claims court — for amounts up to $10,000 (no attorney needed). Fast, inexpensive, and you can use your CSLB complaint documentation as evidence.
• Civil lawsuit — for amounts over $10,000. Attorney recommended. BPC §7031 allows recovery of all compensation paid to an unlicensed contractor.
• Contractor’s surety bond claim — every licensed contractor carries a $25,000 bond. You can file a claim directly against it through the surety company. The bond is shared among all claimants, so act early.
• District Attorney complaint — for fraud, theft, or elder abuse. The DA can pursue criminal charges and restitution orders that carry enforcement power a CSLB citation does not.

File the CSLB complaint AND pursue financial recovery simultaneously. They are parallel tracks, not sequential steps.

Every builder in the VerifiedADU directory is checked against CSLB’s public complaint and disciplinary records before listing. Builders with unresolved complaints, active citations, or recent disciplinary actions are not listed. We recheck every license every 12 hours — if a complaint or enforcement action appears, the builder is flagged for review and may be removed from the directory.