How to check an HVAC contractor’s license

Look up the license on your state licensing board’s website, or with your city or county if the state doesn’t license HVAC. Confirm it is active and covers HVAC work, get a certificate of insurance, and check that technicians who handle refrigerant hold EPA Section 608 certification. NATE certification is voluntary, not a license.

Licensing is state by state

There is no federal HVAC contractor license. Each state decides, and the rules differ a lot. Some license HVAC contractors at the state level; others leave it to cities and counties, or only require registration. Four examples:

Elsewhere, start with your state’s contractor or mechanical licensing board, then check with your city or county building department. Rules also change: California raised its license threshold from $500 to $1,000 in 2025.

Some states also register the people who do the work. In Texas, anyone who assists a licensed air conditioning and refrigeration contractor with maintenance or repair must register as a technician and work under that contractor’s supervision.

How to look up a license

• Get the license number and the exact business name from the quote or contract.
• Search it on the state board’s website, or call the local building department if licensing is local.
• Confirm the status is active and the classification covers HVAC work.
• Check that the name and address match the company you are dealing with.
• Look for disciplinary actions or complaints, which many boards show with the record.
• Ask whether the crew are employees or subcontractors. Subcontractors need their own license where the state requires one.

A license number that belongs to a different company, or a business borrowing someone else’s license, is a reason to walk away.

Insurance

Ask for a certificate of insurance showing general liability coverage and, if the company has employees, workers’ compensation. Have it sent to you directly by the insurer or agent, and check the dates. Some states require insurance or a bond as a condition of the license, but the minimums may be low for a large job.

California is stricter than most: every active C-20 HVAC contractor must carry workers’ compensation insurance or have a self-insurance certificate on file, and the CSLB license record shows the bond and workers’ compensation status. If an uninsured worker is hurt on your property, you could be liable.

EPA Section 608 certification

Federal law requires technicians who maintain, service, repair or dispose of equipment that could release refrigerants to hold EPA Section 608 certification. There are four types: Type I for small appliances, Type II for high-pressure equipment, which includes home central air conditioners and heat pumps, Type III for low-pressure equipment, and Universal for all three. Certification doesn’t expire. It is a technician credential, not a contractor license, so a company needs both. Ask the technician to show the card; for a home central system it should say Type II or Universal.

NATE and other credentials

NATE certification is a voluntary industry credential that technicians earn by passing specialty exams. It is a useful signal of training, not a legal requirement. Manufacturer dealer programs are similar: they may mean extra training or longer warranty options, but they don’t replace a license. For a new system, it is also fair to ask what training the installers have on A2L refrigerants, which new split systems now use.

What to verify before you sign

• License active, in the right classification, in the company’s own name.
• License or registration number printed on the contract; Pennsylvania, for example, requires the registration number on contracts and estimates.
• A current certificate of insurance.
• EPA 608 certification for the technicians who will handle refrigerant.
• The permit pulled in the contractor’s name.
• A written quote with model numbers, scope, warranty and payment terms.
• A physical business address and an office phone number, not only a cell number.
• A deposit within your state’s limits; California caps it at $1,000 or 10% of the price, whichever is less.

Questions

Does every state license HVAC contractors? No. Some license them at the state level, some leave licensing to cities and counties, and some only require general contractor registration. Check both your state board and your local building department.

Is EPA 608 certification the same as a license? No. It is a federal certification for individual technicians who handle refrigerant. The company still needs whatever contractor license your state or city requires.

Is NATE certification required? No. NATE is a voluntary industry certification. It shows a technician passed specialty exams, but it is not a legal requirement.

What if my state doesn’t license HVAC contractors? Check city or county licensing, any state registration, insurance and EPA 608 certification. A permit pulled in the contractor’s name is another sign they are recognized locally.

Sources

• CSLB: C-20 Warm-Air Heating, Ventilating and Air-Conditioning classification — https://www.cslb.ca.gov/about_us/library/licensing_classifications/Licensing_Classifications_Detail.aspx?Class=C20
• CSLB: License requirement for minor work rises to $1,000 (AB 2622) — https://www.cslb.ca.gov/Resources/PressReleases/2024/AB2622.FINAL.pdf
• CSLB: Home improvement contracts — https://www.cslb.ca.gov/Consumers/Hire_A_Contractor/Home_Improvement_Contracts/What_Is_A_Contract.aspx
• CSLB: Workers’ compensation requirements — https://www.cslb.ca.gov/contractors/maintain_license/workers_compensation.aspx
• CSLB: How to find the right licensed contractor — https://www.cslb.ca.gov/consumers/hire_a_contractor/finding_the_right_contractor.aspx
• TDLR: Air Conditioning and Refrigeration Contractors — https://www.tdlr.texas.gov/acr/
• TDLR: ACR technician registration — https://www.tdlr.texas.gov/acr/technician-apply.htm
• Florida DBPR: Construction industry FAQs — https://www2.myfloridalicense.com/construction-industry/faqs/
• Pennsylvania Attorney General: Home improvement contractor registration — https://www.attorneygeneral.gov/businesses-and-organizations/home-improvement-contractor-registration/
• EPA: Section 608 technician certification requirements — https://www.epa.gov/section608/section-608-technician-certification-requirements
• NATE: North American Technician Excellence — https://natex.org/