The Contractors State License Board (CSLB) is the official state authority for contractor licensing in California. TradeOS doesn't replace CSLB — we help you understand the path, then plug you into a trusted network the day you're licensed.
TradeOS does not issue licenses, administer exams, process applications, or handle complaints. For anything official — exam scheduling, application status, license lookup, bonding rules, discipline — go directly to cslb.ca.gov. This page is educational and may not reflect the most current CSLB rules or fees.
CSLB owns the licensing process. Here's how it typically flows.
Be 18+, have a valid SSN or ITIN, and document at least 4 years of journey-level experience in your trade within the last 10 years.
Use CSLB-approved study guides and prep courses. The exam tests trade knowledge plus California contracting law, safety, labor code, and business practices.
File Application for Original Contractor License directly with CSLB. They set the requirements, fees, fingerprinting, and timeline.
Two parts: trade exam (e.g. C-20 HVAC / C-10 Electrical / C-36 Plumbing) and the Law & Business exam. Multiple-choice, computer-based.
Post your $25,000 contractor bond, secure workers' comp if you have employees, pay the initial license fee, and CSLB issues your license number.
CSLB issues 40+ specialty classifications. These are the trades the TradeOS network is built around today.
The HVAC classification — installs, alters, repairs, and services heating, ventilation, and AC systems including ductwork and controls.
Installs, maintains, and repairs electrical systems for light, heat, and power — residential, commercial, and industrial.
Installs, alters, and repairs piping, fixtures, appliances, and appurtenances for water, gas, waste, and venting systems.
Full classification list: CSLB classifications
A non-exhaustive checklist to gather before you start your CSLB application. Always confirm current requirements on cslb.ca.gov.
The day CSLB issues your number, apply to the TradeOS network. We verify your license against CSLB's public records, onboard you, and route real install work — without lead fees.