Home / Licensing / California / C34

C34 Pipeline License (California)

California has 545 active C34 Pipeline holders in the state file as of 2026-10-29¹, the 50th-largest of 64 classes with at least 200 holders. 13 of them expire by 2026-12-28.

Active holders: 545; 0.2% of active California licenses
Expiring by 2026-12-28: 13; 2.4% of holders
Median bond on file: $25,000; 545 bonds
Workers' comp exempt: 25.7%; of 545 with WC status

How many C34 contractors are exempt from workers' comp?

140 of 545 active C34 holders with a recorded status (25.7%) filed an exemption¹, against 48.7% across all California classes.

How do you check a C34 license?

Search by license number or business name on the California license lookup, which reads the same state file.

Other California license classes

C49 Tree and Palm631
D03 Awnings525
D64 Non-specialized654
C32 Parking and Highway Improvement500
C4 Boiler, Hot Water Heating and Steam Fitting693
C31 Construction Zone Traffic Control472
C57 Well Drilling712
C47 General Manufactured Housing451

All 64 classes

Sources

CA CSLB License Master (cslb.ca.gov data portal) (cslb.ca.gov, 2026-10-29)