How to Start an HVAC Business in California

October 29, 2026

Starting an HVAC business in California involves two requirements that catch most newcomers off guard, and both work differently than in many other trades. First, if you install, maintain, service or repair heating and air-conditioning equipment, the law treats that work as contracting. You need a C-20 license from the Contractors State License Board (CSLB) before you bid or perform a job, and that includes service-only work. Second, a C-20 holder must carry workers' compensation insurance even if you have no employees. The owner exemption that other license classes can use does not apply to C-20.

This guide covers those two requirements first, then the rest of the setup in the order most owners find workable: license, bond and insurance, business entity, tax and employer registration, local rules, and federal refrigerant certification.

What You Need Before You Start

Gather these items before you file anything. The bond and insurance take the longest to arrange, so start those early.

• Personal identification and the ownership information the CSLB asks for on its application
• Dated work records showing at least four years of journey-level HVAC experience within the last ten years, plus names and contact details for supervisors or employers who can verify it
• A $25,000 contractor bond from a surety company
• If you form an LLC: an additional $100,000 bond and a liability insurance policy that meets CSLB minimums (see Step 3)
• A workers' compensation policy that covers you as a C-20 holder
• A business name, and if you form an LLC, a California office address and a California agent for service of process
• Funds for the CSLB application fee and initial license fee, the Secretary of State filing fee, and any name reservation fee
• A federal Employer Identification Number from the IRS for tax and payroll accounts
• EPA Section 608 certification, if you will handle refrigerants (see Step 10)

Step 1: Confirm Your Work Requires a C-20 License

The C-20 class covers a contractor who fabricates, installs, maintains, services and repairs the following:

• Warm-air heating systems and water-heating heat pumps that use warm-air appliances
• Ventilating systems with blowers and plenum chambers
• Air-conditioning systems with the air-conditioning unit
• Ducts, registers, flues, humidity and thermostatic controls, and air filters connected to those systems
• Solar-powered heating, ventilating and air-conditioning systems

Service work counts. Under Business and Professions Code (BPC) 7026.1(a)(1), a person who maintains or services air-conditioning, heating or refrigeration equipment that is fixed to a structure is a contractor. A business that only does tune-ups and repairs still needs the license.

A license is required for any job of $1,000 or more in labor, materials and all other items, and for any job that requires a building permit. The small-job exemption is lost by advertising or employing help (BPC 7048), so do not place ads or hire anyone before your license is in place.

Refrigeration is a separate CSLB class (C-38). Check with the CSLB on whether your commercial refrigeration work requires it before you bid on that work.

For the shared mechanics of applying for any CSLB license, read the CSLB contractor license guide at cslb.ca.gov.

Step 2: Meet the Experience and Exam Requirements

To qualify for a C-20 license, you need four years of journey-level experience within the last ten years. The CSLB verifies experience, so keep dated job records and contact information for people who can confirm your work. Gaps or unclear records can slow an application, so review your documentation before you file.

You also must pass the CSLB exams. Expect a law and business exam, the C-20 trade exam, and an asbestos open-book exam. Study for each one separately, and check the CSLB website for current exam formats and content. Do not plan around a fixed timeline. The time from filing to license depends on how your experience and exams are processed, so confirm current timing with the CSLB.

Step 3: Arrange Your Contractor Bond and Liability Insurance

Every CSLB licensee must post a $25,000 contractor bond. An LLC license also requires a $100,000 bond. A surety company will review your credit and may ask for collateral, so start that conversation early.

An LLC license also requires liability insurance with at least $1,000,000 aggregate coverage for up to five listed personnel. The required coverage rises by $100,000 for each additional listed person, up to $5,000,000. Confirm the current insurance requirements with the CSLB before you buy a policy, and make sure your agent's listed personnel match your license application.

Step 4: Carry Workers' Compensation, Even With No Employees

This is the requirement that surprises most HVAC owners. A C-20 license holder must carry workers' compensation insurance even with no employees, because of BPC 7125(b). The owner exemption that other license classes can file through December 31, 2027 is not available to C-8, C-20, C-22, C-39 or D-49 (BPC 7125(b)(2)). From January 1, 2028, the exemption disappears for most licensees.

Get a workers' compensation quote during startup planning, not after you hire your first technician. Ask your insurance agent how a policy handles a solo owner who works in the field, and confirm your exemption status for your license class with the CSLB. Do not budget a premium until you have a written quote.

Step 5: Pay the CSLB Fees

The application fee is $450. The initial license and renewal fees depend on how your business is organized, as shown below. Note that the $450 renewal fee is the sole-owner rate. Other entities pay more.

CSLB fee	Sole owner	Other entities (such as LLCs and corporations)
Initial license	$200	$350
Renewal	$450	$700

Confirm the current fee schedule on the CSLB website before you pay.

Step 6: Form Your Business Entity With the Secretary of State

A sole owner can operate without filing formation documents, but many HVAC owners form an LLC to separate business and personal liability. The California Secretary of State (SOS) Business Programs Division handles entity filings through bizfile Online. The main fees are:

• Articles of Organization for an LLC (Form LLC-1): $70
• Articles of Incorporation for a stock corporation: $100
• Name reservation: $10, which lasts 60 days and cannot be renewed for consecutive periods

An LLC name must include limited liability company, L.L.C. or LLC. Limited may be written as Ltd., and company may be written as Co. The name may not contain bank, trust, trustee, incorporated, inc., corporation or corp. Online filings are normally processed within about 5 business days or less, and paper filings take 10 or more business days. Expedited options are $350 for 24-hour processing, $750 for same-day processing if received by 9:30 a.m., and $500 for 4-hour processing with drop-off and precleared status.

LLC owners should also plan for these requirements:

• A registered agent for service of process: an individual who resides in California, or a corporation that holds a Corporations Code 1505 certificate
• A California office, which need not be a place of business activity
• A Statement of Information (Form LLC-12) for $20, due within 90 days of filing the articles and then every two years during the six-month window ending on the last day of the anniversary month. The Franchise Tax Board (FTB) assesses a $250 penalty after an SOS notice if you miss it.
• California does not allow a domestic series LLC.

Every LLC, LP and LLP organized or registered in California in 2024 through 2026 owes the $800 minimum annual franchise tax from its first year. An LLC whose first taxable year begins in 2027, 2028 or 2029 pays $400 in year one under Revenue and Taxation Code 17941(g)(2), so confirm the first-year amount with the FTB. The LLC fee is $900 once California-source total income reaches $250,000, $2,500 at $500,000, $6,000 at $1,000,000, and $11,790 at $5,000,000.

Corporations file a Statement of Information (Form SI-550) for $25, due within 90 days of filing the articles and then every year. A newly incorporated corporation owes no $800 minimum in its first taxable year. Corporate income tax is 8.84% (S corporations pay 1.5% of net income with an $800 minimum), so confirm your structure with a CPA before choosing it.

Step 7: Register for Sales Tax and Employer Accounts

California has no general state business license. The SOS issues none, and the CDTFA seller's permit is not a business license. Register for the following only as they apply to you:

• CDTFA seller's permit: Register if you sell taxable goods, such as equipment or parts sold to customers. The permit is free. The statewide sales tax base rate is 7.25%, and district taxes raise city rates to between 7.25% and 11.75%. Find your local rate through the CDTFA sales and use tax page.
• Resale certificate: Use one when you buy parts you will resell to customers. No specific form is required.
• EDD employer account: Register with the Employment Development Department at edd.ca.gov before you hire your first employee.

If you hire technicians, plan for the state minimum wage of $16.90 in 2026 and $17.40 beginning January 1, 2027. Verify both figures with the state before you set pay rates.

Step 8: File a Fictitious Business Name Statement if You Need One

If you operate under a name other than your legal name, such as a shortened brand name, you must file a Fictitious Business Name Statement. You file with the county clerk-recorder in the county of your principal place of business (Sacramento County if you have none in California). The filing is due within 40 days of starting business under that name.

The statement must be published in a newspaper once a week for four weeks, and it expires after five years. The statutory filing fee is $10 plus $2 for each additional name or owner (Business and Professions Code 17929), but counties charge more. Tehama County, for example, charges $31 plus $5 for each additional name. The newspaper publication fee is separate. Read the SOS fictitious business name page and confirm your county's current fee.

Step 9: Check Local Business Tax and Installation Permits

Most California cities charge a local business tax or require a registration certificate. Of the 483 cities, 445 report revenue from one, but there is no common formula, so the answer depends on your city. Counties license only regulated activities. Ask your city's finance department or business license office what applies to your address.

Installation work usually requires a building permit from the city or county. Energy and efficiency rules apply to much of this work. This guide does not list specific energy code requirements, so check with the local building department before you bid, since requirements vary by jurisdiction.

Step 10: Get EPA Section 608 Certification (Verify)

Under federal law, anyone who handles refrigerants must hold EPA Section 608 certification from an EPA-approved certifying organization. This is a federal rule, not a California license, so it is separate from your C-20 license. Confirm the current requirements, the certification types, and the approved certifying organizations with the EPA at epa.gov/section608 (verify). Choose the certification that covers the equipment you will service.

Step 11: Set Up Written Contracts and Deposit Practices

Home improvement contracts must be in writing, and the price must be stated in dollars and cents (BPC 7159.5). The down payment is capped at the lesser of $1,000 or 10 percent of the contract price. Build these rules into your contract template before your first bid, and keep a signed copy for every job.

Unlicensed contracting is punishable by a fine of up to $5,000, up to six months in jail, or both for a first conviction (BPC 7028). That exposure applies whenever you bid on or perform covered work without the required license.

Common Mistakes to Avoid

• Treating service calls as exempt. Maintaining and servicing fixed heating and cooling equipment is contractor work under BPC 7026.1(a)(1).
• Advertising or hiring before the license is issued. Doing so removes the small-job exemption (BPC 7048).
• Skipping workers' compensation because you have no employees. C-20 holders must carry it anyway (BPC 7125(b)).
• Budgeting the $450 renewal fee for an LLC. For entities other than sole owners, the renewal fee is $700.
• Forgetting the LLC bond and liability insurance. An LLC license needs a $100,000 bond in addition to the $25,000 contractor bond, plus the insurance described in Step 3.
• Missing Statement of Information deadlines. A missed filing can trigger a $250 penalty.
• Missing the 40-day fictitious business name deadline, or using a name you have not filed.
• Taking a deposit above the cap, or working from a verbal agreement instead of a written contract.

What Results to Expect

A properly organized HVAC business gives you a clear legal footing to bid and perform covered work, and it can make your bonding and insurance easier to explain to customers and lenders. Owners who finish these steps before their first job may avoid the rework that comes from fixing paperwork later. Results depend on your experience, your local market and how you run the business. Nothing in this guide guarantees a license approval, a customer, or revenue.

Next Steps

1. Confirm your license scope with the CSLB, including whether you need C-38 for refrigeration.
2. Assemble your experience records and schedule the required exams.
3. Request bond, liability insurance and workers' compensation quotes.
4. Form your entity and reserve your name if needed.
5. Register with the CDTFA and EDD as your operations require.
6. Confirm local business tax and permit rules with your city and building department.

This article is informational content about starting an HVAC business in California. It is not legal, tax or insurance advice. Requirements, fees and deadlines change, so confirm them with the named agency before you act. Because licensing, bonding, insurance, entity choice and tax obligations affect one another, speak with a qualified California attorney and a certified public accountant before you form your business or sign a bond or insurance contract.