California Subcontractor License Requirements: What GCs Must Verify
California licenses almost all construction work through one board, and it attaches consequences to the GC as well as the sub: an unlicensed sub can become the GC's employee by statute, and the money paid to it can be clawed back. This guide covers the license classes, what to check and how.
The most common mistake: treating an unlicensed sub as a contract problem. In California it is also an employment problem — under Labor Code §2750.5, a contractor who hires an unlicensed sub for licensed work is treated as the employer of that sub and its workers.
California requires a Contractors State License Board (CSLB) license for construction work of $1,000 or more in labor and materials, or any work that needs a permit. Licenses come in three classes — A (general engineering), B (general building) and C (specialty trades such as C-10 electrical, C-36 plumbing and C-39 roofing) — and a sub must hold the class that matches its work. Before a sub starts, confirm on the CSLB website that the license is active, covers the work, and has a current bond, workers' comp on file where required, and a qualifying individual.
In this guide
How California contractor licensing works
The Contractors State License Board (CSLB) licenses general contractors and specialty trades alike. A license is required for any construction, alteration, improvement or repair work of $1,000 or more in combined labor and materials — the threshold rose from $500 on January 1, 2025 — and for any job that needs a building permit, whatever its value.
The narrow minor-work exemption below that line only applies when the work needs no permit and the person doing it has no employees, and the $1,000 is the total for the job: splitting it into smaller invoices does not help.
A CSLB license record carries more than status: it shows the contractor's bond, its workers' compensation on file (or its exemption), its qualifying individual and any disciplinary history. That makes the CSLB lookup the most useful single check in the country — if someone actually reads the whole record.
License classes — A, B and C
Class A — General Engineering
Fixed works requiring specialized engineering knowledge: roads, bridges, dams, pipelines, utilities. Infrastructure GCs meet Class A subs; building GCs rarely do.
Class B — General Building
Structures involving two or more unrelated trades — the license most building GCs hold. A B contractor can take on framing or carpentry alone, but specialty work such as electrical or plumbing on a sub's own scope still needs that sub's C license. A narrower B-2 (residential remodeling) class also exists.
Class C — Specialty
Roughly forty specialty classifications, one per trade — C-10 electrical, C-36 plumbing, C-39 roofing and so on. A sub doing specialty work must hold the C class for it.
Key C-class licenses by trade
| Class | Trade | Note |
|---|---|---|
| C-10 | Electrical | Electricians doing the work also need state certification through the Division of Labor Standards Enforcement |
| C-36 | Plumbing | |
| C-20 | Warm-air heating, ventilating & AC | Separate from C-38 refrigeration and C-4 boilers |
| C-39 | Roofing | Must carry workers' comp even with no employees |
| C-8 | Concrete | Must carry workers' comp even with no employees |
| C-33 | Painting & decorating | Licensed in California, unlike many states |
| C-27 | Landscaping | Includes irrigation and hardscape tied to landscaping |
| C-35 | Lathing & plastering | Stucco and plaster systems |
| C-17 | Glazing |
Don't carry assumptions across state lines: painting, flooring and landscaping are unlicensed in many states and licensed in California.
What GCs should verify
Business and Professions Code §7118 makes entering into a contract with an unlicensed contractor a ground for discipline against the licensee who did it. Checking is how a GC stays on the right side of that line.
The license is Active on CSLB
Not expired, inactive, suspended or revoked. A suspension for a lapsed bond or missing workers' comp shows on the same record.
The classification matches the work
C-10 for electrical, C-36 for plumbing, C-39 for roofing. A sub doing two trades needs both classes.
Bond and workers' comp are current
Every license needs a $25,000 contractor's bond. Workers' comp must be on file for any licensee with employees, and for C-8, C-20, C-22, C-39 and D-49 licensees whether or not they have employees. The requirement extends to all licensees from January 1, 2028.
A qualifying individual is still listed
Every license is qualified by an individual — a Responsible Managing Officer or Employee. When that person leaves, the licensee has 90 days to replace them before the license is at risk. Check that the personnel list is current.
How TrackMyVendor automates this
- CSLB licences are re-checked against CSLB’s own records, so an expiry or a suspension shows on the sub’s record rather than surfacing after an incident.
- The sub’s COI is read on upload, including its workers’ comp row and dates, and sits on the same record as the licence.
- Every check is logged with a timestamp — your record that the licence was active when the sub started.
Bond and qualifier details still come from the CSLB record itself; read them there before a sub mobilizes.
See how California license tracking worksWhat unlicensed work costs in California
California's penalties reach further than most states', and several of them land on whoever hired the unlicensed sub.
The sub's crew becomes the GC's
Labor Code §2750.5 treats a contractor who hires an unlicensed sub for licensed work as the employer of that sub and its workers — for wages, payroll obligations and workers' comp.
Money paid can be recovered
Under Business and Professions Code §7031, an unlicensed contractor cannot sue for payment, and a person who used one can sue to recover everything paid for the work. Courts apply it strictly, with no allowance for not knowing.
Discipline against the GC's own license
Section 7118 makes contracting with an unlicensed contractor a ground for CSLB discipline against the licensee.
Criminal and civil penalties
Contracting without a license is a misdemeanor under §7028, with fines of up to $5,000 and up to six months in jail for a first offense. CSLB can also issue civil penalties of up to $15,000 per citation, with a higher minimum for unlicensed activity from July 1, 2026.
How to look up a California contractor license
CSLB's license check at cslb.ca.gov is the authoritative source. Search by license number — a short numeric ID — for the most reliable result.
- Get the license number before work begins. California requires it on bids, contracts and advertising, so a sub who can't produce it quickly is a flag.
- Confirm Active status and the classification against your scope.
- Read the bond, workers' comp and personnel sections on the same record, and check any disciplinary history.
- Record what you found and when. CSLB licenses renew every two years; note the expiration against your schedule.
How TrackMyVendor automates this
- Subs send their licence number, certificate and W-9 through one upload link — no account, no portal login.
- A licence nearing expiry is on the Monday summary on every plan; on Starter and above the sub is emailed at 90, 60, 30 and 7 days with the link to send the renewal.
- The licence sits next to the COI on the same record, because a current certificate and a lapsed licence can belong to the same sub.
Tracking licenses for California subs?
Everything above is a check you can run by hand. This is what it looks like when it runs itself.
On the free plan
- Your first 25 subs, no credit card
- Subs upload certificates, licences and W-9s through a one-time link — no account, no app
- Every certificate read automatically: coverage rows, limits and each policy’s own dates
- Contractor licences checked against the state board’s own records
- A Monday summary of everything expired or expiring
Per-deadline alerts at 90, 60, 30 and 7 days, sent to your team and to the sub, start on Starter. Compare plans
Stop checking by hand
Set up your roster today
Add your subs — or import the whole list from a spreadsheet on Starter — send each a one-time upload link, and the certificates, licences and W-9s arrive already read. No demo, no sales call, no implementation project.
Start free — no credit card →Up and running in about 10 minutes.
Explore what it does: License verification · AI COI parsing · Expiration alerts · Sub onboarding