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Starting a contracting business in California: CSLB license, bond, insurance and vehicle lettering
Short answerCalifornia contractors need a CSLB license for any job over the contract threshold, a contractor's bond, insurance, a city business license, and the business name plus license number on every commercially registered work vehicle in letters at least 3/4 inch tall.
The checklist, in order
- Pick the classificationB general, or a C specialty (C-10 electrical, C-36 plumbing, C-20 HVAC, C-27 landscaping, C-33 painting, and so on).
- Qualify and testFour years of experience in the trade, law and business exam plus trade exam.
- Bond and insuranceContractor's bond, workers' comp (required even with no employees for some classifications), general liability.
- Business license and EINCity business license; EIN if you have employees or an entity.
- Vehicle letteringBusiness name and license number on every commercially registered vehicle used in the business, 3/4 inch minimum, clearly visible. Plumbing, electrical sign and well drilling contractors also add the business address.
- AdvertisingEvery ad, including the truck, must carry the license number.
What goes on the truck
| Business name | As on the license |
|---|---|
| License | CSLB Lic# 1098765 |
| Address (plumbing, electrical sign, well drilling) | 123 Main St, Pomona CA |
| Phone | Optional but smart |
Both sides, contrasting color, readable from 50 feet in daylight. Two inch numbers is the standard; the rule is legibility, not a fixed height.
Related questions
What size does the license number have to be?
72 point or 3/4 inch tall and 1/2 inch wide, per B&P 7029.6. Most contractors use 1.5 to 2 inches.
What if my truck is registered as personal?
The lettering rule applies to commercially registered vehicles. Many contractors register work trucks commercially anyway for the deduction.
Checked September 2026 against FMCSA, California DMV, CHP, CSLB and BHGS requirements. A plain-English summary, not legal advice; fees and insurance minimums change, so confirm with the agency before filing.