Washington: HVAC contractor licensing, reciprocity and contract rules.

This page lists what Washington publishes about licensing an HVAC or mechanical contractor and contracting with homeowners: who issues the licence, whether one is required statewide, the classes and qualifications, insurance or bond minimums, reciprocity with other states, renewal and continuing education, and the state's home-improvement contract statute if it has one.

It is built for owners of residential HVAC companies, especially those hiring across a state line or opening a second territory. Every entry is a snapshot of what the cited source published on the verification date; it is a research starting point, not legal advice.

Washington, field by field.

Contractor licensing authority

Washington State Department of Labor & Industries (L&I), Contractor Registration — registers HVAC businesses as specialty contractors in the 'Heating, ventilation, air-conditioning and refrigeration (HVAC/R)' specialty (WAC 296-200A-016(28)) or as general contractors. The L&I registration page lists HVAC among the specialties and names plumbing, electrical, elevators, mobile home installation, boilers, and asbestos as work with 'additional requirements for education, examination, and licensing'; WAC 296-200A-016(28) states 'Work in this specialty may also require electrical licensing per chapter 19.28 RCW and/or plumber certification per chapter 18.106 RCW.'

HVAC licence required

Statewide (registration). 'Every contractor shall register with the department' (RCW 18.27.020(1)), and it is a gross misdemeanor to 'Advertise, offer to do work, submit a bid, or perform any work as a contractor without being registered as required by this chapter' (RCW 18.27.020(2)(a)); after a citation, 'A person is guilty of a separate gross misdemeanor for each day worked' (RCW 18.27.020(5)). The HVAC/R specialty contractor 'fabricates, installs, services, and maintains equipment for the purpose of heating and cooling of indoor air', including duct work, pneumatic controls and control piping, insulation, gas piping from service connection to the equipment it serves, and testing and balancing of air handling systems (WAC 296-200A-016(28)); a specialty contractor 'may only subcontract work that is incidental to the specialty contractor's work' (RCW 18.27.010(12)). Electrical work: the HVAC/R specialty 'may also require electrical licensing per chapter 19.28 RCW' (WAC 296-200A-016(28)); WAC 296-46B-920 defines the 06A HVAC/refrigeration electrical specialty, which 'is not limited by voltage, phase, or amperage', and the 06B restricted specialty, which may not perform electrical work where the primary electrical power connection to the system exceeds '250 volts, single phase, or 120 amps'.

Licence classes & qualifications

Registration classes are general contractor and specialty contractor (RCW 18.27.010(5), (12)); HVAC/R is specialty (28) of the 63 specialties defined in WAC 296-200A-016. Registration steps (L&I): register the business with the Department of Revenue (UBI number), obtain a surety bond or an assignment of savings and a general liability insurance policy, file the Application for Contractor Registration (F625-001-000) — 'All signatures on your application must be original and notarized' — and pay the $150.20 application fee. No experience or examination requirement for the HVAC/R specialty registration appears on the L&I registration page or in RCW 18.27.010, .020, .030, .040, .050, .070, or .114; L&I states that contractors working with plumbing, electrical, elevators, mobile home installation, boilers, and asbestos have additional requirements for education, examination, and licensing.

Insurance / bond minimum

Bond: a surety bond 'in the sum of $30,000 if the applicant is a general contractor or $15,000 if the applicant is a specialty contractor' (RCW 18.27.040(1); 2023 c 213 § 3, effective July 1, 2024), which 'shall be continuous', or, in lieu of the bond, an assigned savings account (RCW 18.27.040(8); L&I Assignment of Account form F625-008-000). Insurance: RCW 18.27.050(1) requires insurance of 'fifty thousand dollars for injury or damages to property', 'one hundred thousand dollars for injury or damage including death to any one person', and 'two hundred thousand dollars for injury or damage including death to more than one person'; L&I states this as '$200,000 in public liability and $50,000 property damage' or a '$250,000 combined single limit', with L&I listed as certificate holder.

Reciprocity

No reciprocity or endorsement provision for contractor registration appears on the L&I registration page or in RCW 18.27.010, .020, .030, .040, .050, .070, or .114.

Renewal & continuing education

'This registration is valid for two years from date of issuance, renewal or reregistration' (WAC 296-200A-900); application and renewal fee $150.20 and reinstatement fee $70.90 (L&I; 'The department shall set the fees by rule', RCW 18.27.070); L&I suspends a registration when requirements are not met, 'such as a bond or insurance cancelling or expiring or an unsatisfied judgment'. No continuing-education requirement for contractor registration appears on the L&I registration page or in the RCW 18.27 sections read.

Home-improvement contract rule

RCW 18.27.114 (Disclosure statement required—Prerequisite to lien claim): before starting work for a customer on four or fewer residential units or accessory structures where the bid or contract price totals one thousand dollars or more, or on a commercial building where the price is one thousand dollars or more but less than sixty thousand dollars, the contractor must give the customer the statutory 'NOTICE TO CUSTOMER' disclosure stating the registration number, bond or deposit amount, and registration expiration date and warning that 'THIS BOND OR DEPOSIT MIGHT NOT BE SUFFICIENT TO COVER A CLAIM THAT MIGHT ARISE FROM THE WORK DONE UNDER YOUR CONTRACT' and that 'YOUR PROPERTY MAY BE LIENED' if suppliers or workers are not paid; 'No contractor subject to this section may bring or maintain any lien claim under chapter 60.04 RCW' without alleging and proving the disclosure was provided; failure to comply 'shall constitute an infraction'; the contractor must retain a signed copy for 'a minimum of three years' (L&I Model Disclosure Statement F625-030-000, for residential jobs of $1,000 or more and commercial projects of $1,000 to $60,000). L&I also states the registration number must appear on all business communications, including 'business cards, Yellow Page ads, newspaper ads, internet ads, estimates and bid proposals'. No statute requiring a written home-improvement contract, capping deposits, or granting a cancellation window beyond the federal three-business-day rule (16 C.F.R. § 429.1) was located in the official sources read.