Skip to content
State files updated Oct 27, 2026
Look up a contractor
MenuClose

Home / Licensing / California / C20

C20 Warm-Air Heating, Ventilating and Air-Conditioning License (California)

California has 11,653 active C20 Warm-Air Heating, Ventilating and Air-Conditioning holders in the state file as of 2026-10-261, the 7th-largest of 64 classes with at least 200 holders. 372 of them expire by 2026-12-26.

Active holders
11,653
5.0% of active California licenses
Expiring by 2026-12-26
372
3.2% of holders
Median bond on file
$25,000
11,651 bonds
Workers' comp exempt
0.1%
of 11,653 with WC status

What does the California Warm-Air Heating, Ventilating and Air-Conditioning license require?

C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor. Related: C-4 Boiler/Hot Water Heating/Steam Fitting; C-43 Sheet Metal. Active C-20 must carry WC even with no employees. Refrigerant (EPA 608) not addressed on CSLB class page.2

Exam

Two exams: (1) Law & Business and (2) trade exam for the classification (no trade exam for C-61).3

Bond

$25,000 contractor bond (or $25,000 cashier's check).1

All California license requirements

How many C20 contractors are exempt from workers' comp?

8 of 11,653 active C20 holders with a recorded status (0.1%) filed an exemption1, against 48.7% across all California classes.

How do you check a C20 license?

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

Sources

  1. CA CSLB License Master (cslb.ca.gov data portal) (cslb.ca.gov, 2026-10-26)
  2. Contractors State License Board (CSLB): classes (cslb.ca.gov)
  3. Contractors State License Board (CSLB): exam (cslb.ca.gov)