Advertising law: the license number on every ad, every contract and the side of the van, and the review habit that actually brings work
In one paragraph
California treats your advertising as part of the license record. The license number goes on every contract, bid and ad, and on the van in type at least three-quarters of an inch high. You may only advertise work in classifications you hold, so 'electrical and solar' is a misdemeanor for a C-10 alone. And the word 'bonded' is a ground for suspension. Get those four rules onto the van, the estimate and the Google Business Profile once, then spend the marketing energy where it pays: a review request at the end of every job.
The rule
Every licensee must include the license number in all construction contracts, subcontracts and calls for bid, and in all forms of advertising (B&P 7030.5), and must display the business name and license number on every commercially registered vehicle used in the business in type of at least 72 points or three-quarters of an inch (B&P 7029.6). Advertising for work in a classification you do not hold is a misdemeanor with a fine of $700 to $1,000 (B&P 7027.1). Any reference in advertising to the CSLB bond is a ground for suspension (B&P 7071.13).
Why it matters
The van and the Google listing are the two ads a homeowner actually sees. A van with no license number is a CSLB citation waiting at the next sting, and a listing that says 'electrical and solar' from a C-10 without a C-46 is a misdemeanor in writing. These are five-minute fixes that some contractors never make, and CSLB's enforcement staff look for exactly them.