California HVAC license requirements and insurance

To work for yourself as an HVAC contractor in California, you need the C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor license. The state sets no minimum liability insurance, and workers' comp is required once you have employees. A $25,000 bond is required.

Checked by the Trades by State editor on 2026-09-07 Based on 29 official pages, listed at the bottom Something wrong? Tell us

License you need: C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor Renew Every two years for an active license. An inactive license renews every four years
Insurance you must carry: No state minimum customers usually ask for $1,000,000
Workers' comp: Required as soon as you hire anyone
Credit score: None or take a 14-hour course
To protect your pay, send notice by: Within 20 days of your first day of work on the job (first day on January 10 means notice by January 30). A late notice still counts, but only for work done in the 20 days before you served it and after.

Turn this into a checklist

1 What stands out in California for an HVAC contractor What is this?

The things people get wrong or do not expect about California, in a few sentences.

A C-20 contractor must have workers' comp insurance even with no employees. It is one of five classifications that cannot claim the no-employee exemption, alongside concrete, asbestos abatement, roofing, and tree service. A license qualified by a responsible managing employee is in the same position.
There is one contractor license, not a journeyman and master ladder. Four years in the last ten at journey level, or as a foreman, supervising employee, contractor, or owner-builder. Then two exams, a $25,000 bond, and the C-20 is issued to you or your company.
The state sets no liability insurance minimum for a sole owner or corporation. An LLC must carry at least $1,000,000.
A furnace or air-conditioning unit is a fixture for sales tax. You charge the customer tax on the unit. Ductwork is a material, so you pay tax when you buy it and charge the customer nothing on it.
If you were hired by a general contractor, send a preliminary notice within 20 days of starting or you can only lien for work done in the 20 days before you finally send it.
Anyone who handles refrigerant needs the federal EPA Section 608 certificate on top of the C-20. It never expires.

Checked by a person against the official page

·6 official pages

2 Who issues HVAC contractor licenses in California? What is this?

Contractors State License Board (CSLB), part of the California Department of Consumer Affairs issues HVAC licenses in California.

Name	Contractors State License Board (CSLB), part of the California Department of Consumer Affairs
Website	https://www.cslb.ca.gov/
Look up a license	https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/CheckLicense.aspx
The law	Business and Professions Code division 3, chapter 9 (Contractors State License Law, sections 7000 and following)
The rulebook	Title 16 California Code of Regulations, division 8 (sections 810 and following)

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3 California HVAC contractor license requirements and fees What is this?

California has 1 license type that matter to an HVAC contractor. The C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor needs four years of work at journey level (a fully qualified worker who needs no supervision), or as a foreman, supervisor, contractor, or owner-builder, in the last ten years. Up to three of the four years can come from an apprenticeship, technical training, or a degree, but at least one year must be hands-on work. Someone who saw you do the work, such as an employer, foreman, fellow journeyman, union rep, or building inspector, must sign a Certificate of Work Experience.

C-20 Warm-Air Heating, Ventilating and Air-Conditioning Contractor

Anyone who contracts to do heating, ventilation, or air-conditioning work in California that needs a contractor license. A sole owner, partnership, corporation, or LLC can hold it. The license names one qualifying individual who meets the board's experience and exam requirements and is answerable for how the company does its work

What you can work on

Fabricates, installs, maintains, services, and repairs warm-air heating systems and water heating heat pumps with their warm-air appliances.
Also ventilating systems with blowers and plenum chambers, and air-conditioning systems with the air-conditioning unit.
Also the ducts, registers, flues, humidity and thermostat controls, and air filters that go with them.
Includes systems that use solar energy.

Experience required

Four years of work at journey level (a fully qualified worker who needs no supervision), or as a foreman, supervisor, contractor, or owner-builder, in the last ten years.
Up to three of the four years can come from an apprenticeship, technical training, or a degree, but at least one year must be hands-on work.
Someone who saw you do the work, such as an employer, foreman, fellow journeyman, union rep, or building inspector, must sign a Certificate of Work Experience.

Training required

None required beyond the experience above

Exam

Yes, two computer exams run by PSI Exams: a Law and Business exam and a C-20 trade exam. You get 3.5 hours for each, 18 months from the date your application is accepted to pass both, and can retake a failed exam after 21 days.

Fees

Application	$450
Each exam (paid to PSI)	51.43
Both exams (paid to PSI)	$102.86
First license, sole owner	$200
First license, company or partnership	$350
Fingerprints (state)	32
Fingerprints (FBI)	17
Fingerprint scanning fee	Varies by location
Renewal, sole owner	$450
Renewal, company or partnership	$700
Late renewal, sole owner	$675
Late renewal, company or partnership	$1,050
Adding a license type	$230

Renewal

Every two years for an active license. An inactive license renews every four years

Training hours each year

Taken from the linked page, not separately checked

·8 official pages

4 How much insurance does an HVAC contractor need in California? What is this?

California sets no minimum liability insurance for this license. Customers and general contractors usually ask for $1,000,000 anyway. Workers' comp is required once you have employees.

Minimum liability insurance	None required by the state
Type of policy	None required by the state for a sole owner, partnership, or corporation
Minimum liability insurance for an LLC	$1,000,000
About LLC insurance	An LLC must carry liability insurance of at least $1,000,000 if it has five or fewer people on record with CSLB. Add $100,000 for each extra person, up to $5,000,000. The insurer must be licensed in California or an eligible surplus line insurer.
Who this applies to	Only licenses held by an LLC
Who must be named on the certificate	CSLB. Name the board as the certificate holder on the workers' comp certificate, and take the policy out in your licensed business name, not your own name
Workers' comp required?	Yes, always. Every active C-20 licensee must have a Certificate of Workers' Compensation Insurance or a Certificate of Self-Insurance on file with CSLB, whether or not they have employees.
Who can opt out	None for C-20. The no-employee exemption other trades can file is not open to C-8, C-20, C-22, C-39, or C-61/D-49 licensees. From January 1, 2028, no trade can file it.

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·6 official pages

5 Does California check your credit for an HVAC contractor license? What is this?

California does not check your credit for this license.

Credit score you need	None
If your score is lower	Nothing to do. The board does not list a credit score or a financial statement among its license requirements
About the bond	The $25,000 contractor bond is its own requirement, not a test of your finances. It protects customers if you do not finish the work

Checked by a person against the official page·cslb.ca.gov

6 Does an HVAC contractor need a bond in California? What is this?

California requires a bond of $25,000. A bond is a promise, backed by an insurance company, that customers can be paid if you do not finish the job.

Does the state require a bond?	Yes
Amount	$25,000
Bond for the qualifying person	$25,000
Bond for LLC employees	$100,000

A bond (a promise, backed by an insurance company, that customers and workers can be paid if you break the rules) of $25,000 must be on file before the license is issued, or a $25,000 cashier's check instead. If the license is qualified by a Responsible Managing Employee, or by an officer who owns less than 10 percent of the company, a second $25,000 Bond of Qualifying Individual is needed. An LLC also needs a $100,000 employee and worker bond. The bond must come from a surety licensed by the California Department of Insurance.

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·3 official pages

7 Federal rules that also apply What is this?

Rules from the US government that apply to an HVAC contractor in California on top of the state's own.

EPA refrigerant certification	Anyone who maintains, services, repairs, or disposes of equipment that could release refrigerant must hold EPA Section 608 certification, on top of the C-20. There are four types. Type I for small appliances, Type II for high-pressure systems (most home and light commercial AC), Type III for low-pressure chillers, and Universal for all three. The EPA does not run the test or issue the card. You take it through an EPA-approved certifying organization.
Expires	No

EPA refrigerant certification

Anyone who maintains, services, repairs, or disposes of equipment that could release refrigerant must hold EPA Section 608 certification, on top of the C-20.
There are four types.
Type I for small appliances, Type II for high-pressure systems (most home and light commercial AC), Type III for low-pressure chillers, and Universal for all three.
The EPA does not run the test or issue the card.
You take it through an EPA-approved certifying organization.

Expires

Taken from the linked page, not separately checked

·2 official pages

8 Where must a California HVAC contractor show the license number? What is this?

In California: your license number must appear in every construction contract, subcontract, and call for bid, and in every form of advertising. Advertising means business cards, contract proposals, signs, billboards, vehicle lettering, brochures, flyers, newspaper and magazine ads, radio and TV, websites, online posts, and directories.

The rule	Your license number must appear in every construction contract, subcontract, and call for bid, and in every form of advertising. Advertising means business cards, contract proposals, signs, billboards, vehicle lettering, brochures, flyers, newspaper and magazine ads, radio and TV, websites, online posts, and directories.
On your vehicles	Show the business name and license number on every commercially registered vehicle where it can be seen, in letters at least 72-point type, or three quarters of an inch high and wide
If you forget	Leaving the number out of your advertising brings a civil penalty of $100 to $1,000 for a first offense. The vehicle rule sets no fine of its own, but the board can act against your license

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·4 official pages

9 Does an HVAC contractor charge sales tax on labor in California? What is this?

Whether California taxes your labor, your materials, or neither.

See how this compares in every state: Sales tax on labor for plumbers and HVAC contractors by state

Materials	You are the consumer of materials (ducts, pipe, wire, refrigerant line, anything that loses its identity once installed). You pay sales tax when you buy them and do not charge the customer tax on them.
Fixtures (things attached to the building)	You are the retailer of fixtures (items that stay recognizable after installation). Publication 9 and Regulation 1521 list air-conditioning units, furnaces, boilers, and heating units as fixtures. You charge the customer sales tax on the unit. In a lump-sum contract the tax is worked out on what the unit cost you.
Installation labor	No sales tax
Homes versus businesses	Same rules for a home and a business
New buildings	Same rules as repair and remodel
Repairs	In a lump-sum repair you pay tax on the parts and charge the customer nothing. If you bill the parts separately from the labor, or you replace the whole unit, you charge the customer tax on the parts or unit.
When you quote one total price	You pay tax on materials at cost and report tax on fixtures at your cost. Listing materials, labor, and tax separately on the invoice does not turn a lump-sum contract into a time-and-material one.
When you bill time and materials	You are still the consumer of materials unless you bill sales tax on a marked-up materials charge, or the contract passes title to the materials before installation and states their price separately. Then you are the retailer and charge tax on the materials.
Seller's permit	Needed, because selling and installing a furnace or AC unit makes you a retailer of fixtures.
Tax rate	7.25 percent statewide, plus district taxes of 0.10 to 2.00 percent in many cities and counties

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·4 official pages

10 Getting paid: lien and notice deadlines for a California HVAC contractor What is this?

If you are not paid in California, a lien on the property is your backstop, but only if your notice goes out on time: within 20 days of your first day of work on the job (first day on January 10 means notice by January 30). A late notice still counts, but only for work done in the 20 days before you served it and after.

Who has to send a notice	Everyone who wants to keep the right to file a lien, except workers paid by the hour. If you were hired by the property owner, you only need to send the notice to the construction lender, if there is one. If you were hired by a contractor, send it to the owner, the direct contractor, and any lender.
Send your notice by	Within 20 days of your first day of work on the job (first day on January 10 means notice by January 30). A late notice still counts, but only for work done in the 20 days before you served it and after.
File your lien by	If the owner hired you, record the lien within 90 days of the project being finished, or within 60 days after the owner records a notice of completion or cessation, whichever comes first (project finished March 1 with no notice recorded means lien by May 30). If a contractor hired you, the 60 days becomes 30 days.

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·4 official pages

11 How much does it cost to become an HVAC contractor in California? What is this?

The government fees on this page add up to about $800 in California. Add insurance, tools, and a vehicle to get the real number.

Government fees, added up	$800

Does not include the $25,000 bond premium, the workers' comp policy every C-20 must carry, the EPA 608 test, live scan rolling fees, tools, a vehicle, or city permits and business licenses

Our estimate

12Where these numbers come from

The labels under each table are explained on how to read a page.