TradeCheck

1 California Plumbing Contractors Are Working on an Expired License

An analysis of all 18,172 plumbing contractor licenses published by the California Contractors State License Board, as of August 17, 2026.

18,172licenses analysed
1expired
0.0%of the trade
10counties ranked

CSLB republishes its full licensee file daily. We loaded every plumbing contractor record and compared the expiration date on each against today's date. 1 licenses, 0.0% of the trade, have already lapsed.

Counties with the highest expiry rate

Ranked among counties with at least 50 licensed plumbing contractors.

CountyLicensed ExpiredRate
Los Angeles County3,48910.0%
Alameda County36300.0%
Butte County6700.0%
Contra Costa County37500.0%
El Dorado County9600.0%
Fresno County15500.0%
Humboldt County5000.0%
Kern County18100.0%
Marin County12100.0%
Merced County6300.0%

Method

Source file: CSLB public license listing, downloaded August 17, 2026. A license counts as expired when its published expiration date is earlier than the date of analysis. We do not adjust for grace periods, so a licensee who renewed today may still appear here until the next daily file. Counties with fewer than 50 licensees are excluded from the ranking to avoid small-sample noise.

Full methodology →