California's Contractors State License Board tracks 247,176 active licensed contractors across the trades ContractorRoster mirrors, divided across more than 40 specialty and general classifications — and the most common reason a homeowner ends up paying twice for the same job isn't fraud. It's hiring a licensed contractor whose classification doesn't cover the work in the contract.
A C-39 roofing license signing off on attic-fan electrical. A C-36 plumber framing a bathroom addition. On paper the license is active. In court it's the same as being unlicensed.
CSLB is also one of the few state portals that surfaces bond status and workers' comp status alongside the license itself — a real advantage over states that hide that data behind a separate request. This guide walks the 3-step CSLB verification, decodes the license-status codes that matter, and lists the four red flags that catch most homeowners and out-of-state sourcers who think they did the homework.
Why verification matters more in California than most states
Hiring an unlicensed contractor in California has three concrete consequences that don't apply in lighter-touch states.
The $500 threshold is unusually low. Under California Business & Professions Code §7028, any construction work where the combined labor and materials value is $500 or more requires an active CSLB license. Smaller-dollar repair work doesn't, but the bar is set well below what most kitchen, bath, or roof jobs cost — meaning the vast majority of residential work is in scope.
You can recover everything you paid them. This is the California fact most homeowners — and most contractors — don't know about. Under B&P Code §7031(b), a person who uses an unlicensed contractor for work requiring a license is entitled to recover all compensation paid to that contractor, even if the work was performed competently and the homeowner suffered no actual damages. The statute is a disgorgement remedy: the legislature decided the deterrent matters more than fairness to the contractor. Courts have applied it strictly. If the license wasn't active for the entire duration of the work, the contractor has to give the money back.
Unlicensed contracting is a misdemeanor. B&P Code §7028 makes contracting without a license a criminal offense, with escalating penalties for repeat offenses and for unlicensed work performed in a declared disaster area. CSLB runs sting operations. This is not theoretical.
Those three together are why the CSLB check is non-optional, even on a referral from someone you trust.
The 3-step CSLB verification process
Step 1 — Open the licensee search. Go to cslb.ca.gov and click "Check a License" in the top navigation, or jump directly to the instant license check at cslb.ca.gov/OnlineServices/CheckLicenseII/CheckLicense.aspx. Both land at the same CSLB-hosted portal.
Step 2 — Search by name or license number, then cross-check both. Unlike some state boards, CSLB's portal is happy to take either input. The play is to search by name first, confirm the license number matches what you were handed, then search by license number to confirm it doesn't pull up a different business. License numbers in California are personal to the qualifying individual and travel with them — a license printed on a business card may belong to someone who left the company two years ago.
Step 3 — Read all four status fields, not just the license status. This is where CSLB's portal earns its reputation. A clean record shows you four things, and you should look at each one separately:
- License Status — Active, Suspended, Expired, Revoked, or Cancelled. Active is the only one that lets the contractor legally take your money for licensed work. Suspended is the California gotcha: the license number still resolves on the portal and the business may still be operating, but the contractor cannot legally contract for new work until the suspension is lifted. Suspensions happen for unpaid judgments, lapsed workers' comp, bond issues, or disciplinary action.
- Classifications — A (general engineering), B (general building), B-2 (residential remodeling), or one of the roughly forty C-XX specialty classes (C-10 electrical, C-20 HVAC, C-36 plumbing, C-39 roofing, C-46 solar, and so on). The classification has to match the scope of the work. A B-licensed general building contractor can take on most residential work directly, but cannot self-perform a single trade unless the job involves at least two unrelated trades or the contractor also holds the relevant C-XX.
- Bond Status — every active CSLB license carries a $25,000 contractor's bond by statute. The portal shows the bond company, bond number, and effective date. A license active but bond lapsed is a contractor you cannot legally hire.
- Workers' Comp — either a current workers' compensation insurance policy with carrier and policy number, or a CSLB-filed exemption (only valid if the contractor has no employees). A roofer with the exemption box checked and three guys on the truck is a problem — both for liability if someone gets hurt on your property and as a signal of how the business is being run.
Four red flags most homeowners miss
The classification doesn't cover the scope of work. This is the single most common California verification miss. A C-39 roofing license cannot legally perform the electrical work for a roof-mounted solar array (that needs a C-10 or C-46). A C-36 plumbing license cannot frame a bathroom addition (that needs a B). The portal shows the classification plainly; the contract you're about to sign rarely calls out the mismatch. Read both and compare.
The license is held by an RME or RMO who isn't actually on the job. Under B&P Code §7068, every CSLB license is qualified by a real human — either a Responsible Managing Officer (RMO, an officer of the licensed entity) or a Responsible Managing Employee (RME, a bona fide employee). The qualifier is supposed to exercise direct supervision and control over the licensed business. In practice, license-renting (where a qualifier sells their name to a business they have nothing to do with) is one of CSLB's most-investigated violations. If the qualifier on the portal isn't anyone you've met or spoken to about your job, that's worth a direct question.
The license is current but bond or workers' comp is lapsed. The portal will show you a green Active license with a red bond-suspended or workers'-comp-expired flag right next to it. Most people see "Active" and stop reading. The bond exists specifically to give you recourse if the contractor walks off the job; without it, the license-status check is half-done.
The license is current but the contract value exceeds the qualifier's experience cap. Less common but worth knowing about. A CSLB qualifier's experience on the original application sets an implicit ceiling on the size of jobs the board considers them competent for. A two-person shop with an active B license taking on a $4 million tenant improvement is technically licensed and technically a red flag, particularly if you're a property manager or developer with downstream liability.
What CSLB data doesn't tell you
Worth being honest about the limits of the public portal so you know where to look further.
Complaint records are partially public. The portal surfaces disciplinary actions that have resulted in a formal accusation, citation, or final order. Open complaints that haven't reached that stage do not appear. For a fuller picture, CSLB accepts public records requests under the California Public Records Act, but you should expect a delay measured in weeks.
Mechanic's lien history isn't centralized. Liens are recorded at the county recorder's office where the property sits. A contractor with a clean CSLB record can still have a pattern of recording liens against homeowners after disputed jobs — and you'd have to pull county records in every county they work in to see it.
RME and RMO turnover isn't always reflected immediately. CSLB allows a period for license-qualifier changes to be reported and recorded. A license that recently changed qualifiers may show stale information for a window.
Out-of-state contractors operating in California without CSLB licensure are not tracked at all. California does not honor reciprocal licensure from any other state for general contracting. Anyone working a job over $500 in California has to be CSLB-licensed, full stop, regardless of what they're licensed for elsewhere.
Sourcing licensed California contractors at scale
ContractorRoster maintains a continuously-updated mirror of California's CSLB licensed-contractor data with phone, email, website, and Google ratings layered in. For one-off verification of a name you've already been handed, the free CSLB Check a License portal above is the right tool — it is the source of truth.
For sourcing multiple licensed contractors at scale — a property manager building a vendor roster across the Bay Area, a supplier launching into Los Angeles, a developer running an RFP for a multi-property rehab — our $39 CSVs at /california pull the same CSLB data pre-enriched with the contact info CSLB doesn't surface. California accounts for roughly 40% of the 614,114 active licenses we mirror across 13 states.
Either way, the verification rules above don't change. Even from a pre-enriched roster, the last check before you sign is to pull the license up on the CSLB portal and read all four status fields yourself.
Next step
Browse licensed California general contractors, electricians, plumbers, HVAC contractors, or roofers — every record sourced from the CSLB registry above, with the contact info CSLB doesn't publish.
Or run a one-off check at the official CSLB Check a License portal.