There's no Colorado HVAC license. Here's what your Denver HVAC license covers and what your business needs in the first 30 days

Published November 3, 2026 · Colorado Revised Statutes 2026, Denver's 2025 building code and license policies, the Pikes Peak, Aurora, Lakewood, Boulder and Fort Collins licensing rules, Colorado's furnace emissions law and EPA's refrigerant rules checked November 3, 2026

• Free. The printable checklist comes by email. The full checklist and the job table are on this page too, nothing held back.
• Deepsel is our product: free estimate, invoice and scheduling software for contractors (scheduling and dispatch, quotes, invoicing, card payments). The section before the FAQ says where it fits and where it doesn't.
• Not legal advice. Every rule links to the statute, code section, policy or agency page it comes from. Ask Denver Contractor Licensing, the city you're working in or a Colorado attorney before you bet a job on my reading.

Colorado doesn't license HVAC contractors. The state licenses electricians and plumbers, and cities license heating and cooling, so your Denver license is good in Denver and nowhere else.^{1, 3} Denver licenses the company through a supervisor: one person with a Denver supervisor certificate, working full time for your company and no other, makes the license valid.⁷ Your class decides the work. Denver's residential HVAC license covers furnaces, ductwork, gas piping to the appliance and air conditioning up to 5 tons in houses and duplexes. Heating and Ventilating Class A reaches commercial buildings but covers no split-system air conditioning, and boilers need a hot water license.⁴ Denver also sets insurance: $1 million per occurrence and $2 million aggregate general liability, plus workers' comp.⁴ The state still reaches you in five places: gas piping permits outside the big cities, the line-voltage wiring that belongs to electricians, workers' comp, sales tax on the equipment you sell, and a 2026 limit on furnace emissions.^{1, 21, 22, 23}

An Illinois owner described the same setup on Reddit: "i run a 2man hvac startup company with a partner in the state of Illinois, which does not have a statewide license." Colorado works the same way, and the guides that rank for "Colorado HVAC license" stop at the exam. This page picks up after it, for a company with a Denver mechanical license: what each Denver class covers, the supervisor behind the license, where the license stops, the other cities you'll work in, the permit and utility steps, a job-by-job table and a checklist for the first 30 days. If your Denver card says Plbg A, you hold the plumbing registration, which covers gas piping and water heaters but not furnaces or air conditioning; the Colorado plumbing license article is yours. The electrician's side is in the Colorado electrical license article, Denver's building classes are in the Colorado contractor license article, and the paperwork for your quotes is in what your Colorado contract must include.

The checklist also comes as a printable sheet with blanks for your license, certificate, permit, policy and EPA 608 card numbers and your renewal dates. Get it three ways: make your own copy in Google Docs (lands in your Drive), download the Word version (.docx), or download the PDF. Pick a format, enter your email and I'll send the links.

Colorado HVAC license requirements: what the state controls without an HVAC contractor license

Colorado's professions title has a licensing law for electricians and one for plumbers and none for heating, ventilating, air conditioning or refrigeration.¹ DORA, the state's licensing agency, tells homeowners: "Not all occupations are licensed, such as roofers and general contractors. However, laws may exist in your county".³ So the license question moves to the city where the job is. But state law still touches most HVAC jobs:

Denver mechanical licenses: what each Denver HVAC license covers

Denver issues nine mechanical licenses. Each license names what you may "install, add to, alter or repair," and each needs a supervisor certificate of the matching type. Here are the ones HVAC companies hold. The short names are how they show on Denver's license search and on our list of new licenses.

Sources: Denver's license policy 25-DCBC 120A⁴ and its mechanical certificates page.⁵ Every class includes low-voltage wiring "which does not exceed 48 volts and is not enclosed in a conduit or raceway." Denver also licenses Boilermaker contractors for boiler erection. A window air conditioner needs no license or permit.⁴

Three things in that table catch people:

• Class A heating isn't air conditioning. A Heating and Ventilating Class A license covers rooftop units and other packaged equipment up to 50 tons, but not a split system with a separate condenser. A commercial shop that installs splits needs Refrigeration Class A too.
• The residential HVAC license stops at 5 tons and at duplexes. A small apartment building is outside it, and so is a 6-ton system in a big house.
• Boilers are a separate license. Hydronic heat needs Hot Water (homes) or Steam and Hot Water (anything). HVAC Residential Only doesn't list it.

If your card or the license search just says "HVAC," it's almost certainly the residential license, Denver's only class with air conditioning in its name. Check the class on the card itself before you quote a commercial job.

The Denver supervisor certificate and the company license

"Contractor licensing in Denver is a two-step process: A license applicant must hold a supervisor certificate ... or employ someone who holds a supervisor certificate, before applying for a contractor's license."⁶ The certificate belongs to a person. The license belongs to the company, and "A contractor must have a certified supervisor or registrant as an employee or principal."⁷

Getting the certificate means notarized letters that show "WHAT, WHEN AND WHERE" you gained the experience, from past employers or customers. "If you are the owner of the company, you must go to previous employers or clients that you have done work for as you cannot be your own reference." Then the ICC exam, F32 for the residential classes or F29 for the Class A licenses. Review takes about 14 to 20 business days, you have 90 days to pay once approved, and a second refusal means a six-month wait.⁵ Denver doesn't honor other cities' certificates, though "the building official may accept the examination results of the issuing jurisdiction."⁷

The license application adds the Supervisor Statement of Responsibility, where the supervisor signs that they're employed "in an ACTIVE, FULL-TIME capacity as SUPERVISOR for all work performed under the company's" license. If the supervisor isn't an owner, officer, partner or member, they also need a letter on company letterhead naming them "Supervisor of Record," signed by an owner. You upload your Secretary of State documents, and every person who signs has to appear on those filings.⁶

The fees are low: $60 for the certificate and $250 for each mechanical license type, both every three years, and each license type is paid separately.⁶ The rules around them carry more weight:

• One company. The certified supervisor "Is employed by only one contractor at any given time" and "is responsible for all actions in connection with the license and all permits obtained under the license."⁷
• When the supervisor leaves. Tell Denver within 3 working days. You then have 30 working days to get a new certified supervisor, after which "the license shall be deemed suspended."⁷
• Changes. A name or address change goes to Denver within 15 days. A new legal entity, say moving from sole proprietor to an LLC, needs a new license within 30 days.^{6, 7}
• Renewal. Licenses and certificates renew every three years. You can renew from 30 days before the date to a year after, but "No work shall commence or continue after the date of expiration."^{6, 7}

If you're asked to be someone else's supervisor

New certificate holders get asked to put their certificate behind another company. One owner described it on Reddit: "Was already doing sub work before I quit my day job “under someone else’s license”". In Denver the floor is plain: one company at a time, full time, and responsible for every permit under that license. "Allowing one's license or certificate to be used by another person" is grounds to suspend or revoke, for up to three years.⁷ Aurora goes further and wants the supervisor to give "personal supervision at the work, job or project site."¹⁵ What the arrangement pays and what it can cost you is a topic of its own. For scale, the Bureau of Labor Statistics puts the Colorado median for HVAC mechanics and installers at $31.35 an hour in May 2025.³⁶ The short version: every permit pulled under the license is yours.

Insurance and bonds: the figures Denver and the other cities set

Denver's code says a licensed contractor carries insurance "commensurate with the type of project and scope of work as defined by the building official in policy."⁷ The policy is the last page of the license policy, and it applies "for all scopes of work and licensure types":⁴

• General liability: "$1M per occurrence and $2M aggregate, minimum."
• Workers' compensation: "$100,000 per occurrence and $250,000 aggregate, minimum (or Rejection of Coverage for a contractor with no employees)."

The other cities line up close to that. The Pikes Peak Regional Building Department wants $1,000,000 / $2,000,000 for mechanical contractors, with the department as certificate holder and 10 days' notice of any cancellation, and a lapse suspends the license.¹⁴ Boulder wants the same limits with the City of Boulder as additional insured, and Fort Collins a $2,000,000 general aggregate.^{17, 18} I found no bond for mechanical work in Denver, Pikes Peak, Aurora, Lakewood, Boulder or Fort Collins. The order matters too. "To get insurnace i need registered LLC in my state," an HVAC owner wrote (Reddit), so form the company with the Secretary of State first, then buy the policy in that exact name. Pikes Peak rejects a certificate whose named insured doesn't match the license.¹⁴

Where your Denver HVAC license stops

The license covers the equipment, the air side and the gas line to the appliance. Here's where each edge lands.

• The circuit to the condenser. The breaker, circuit, disconnect and whip are electrical work under state law, and Denver puts disconnect switches and "Any other equipment or appliance with a rated voltage of over 50 volts" on its electrical permit list.^{1, 8} Denver's replacement guide says residential equipment installs "require a mechanical and electrical contractor to obtain a quick permit," and on commercial jobs "an electrical contractor shall pull an electrical quick permit" for every reconnection.⁹ State law lets an appliance seller connect an appliance when no "electrical wiring of the structure" is needed, which is how some shops read a straight swap.¹ In Denver, plan on an electrician for every job with line voltage.
• Thermostat and control wiring. Yours. Denver's licenses include wiring of 48 volts or less outside conduit, and the state's electrical law exempts environmental controls and class 2 circuits.^{1, 4} A line-voltage thermostat on baseboard heat is an electrician's.
• Gas piping. In Denver it's inside the HVAC, heating, hot water and gas service licenses, so you run the line to the furnace and pull the permit.⁴ Swapping an appliance onto an existing gas connection isn't "gas piping" under state law.¹ Outside the cities with their own inspectors the picture changes: the plumbing law says "the person making the installation, who must be a qualified applicant, shall apply for a permit," and a qualified applicant is a master plumber with a registered plumbing contractor, or a homeowner.¹ The board's rule issues fuel gas piping permits "in the name of the qualified applicant or registered contractor performing the work."²⁰ Yet the state's gas piping form still has a "Gas Pipe Installer" box and its online system a "Fuel Gas Pipe Installer" login.¹⁹ Until the board settles that, ask it before you run new pipe in a state-inspected county, or sub the line to a plumbing contractor.
• Water heaters. Not in the HVAC or heating and ventilating scopes. They sit in the Plumbing A registration, and venting them is listed under Gas Service.⁴ Sub them out unless you add a license.
• Humidifiers, boiler fill lines and condensate. State law needs no plumbing license for the "related water piping and the indirect waste piping" of heating and air conditioning installations, and of humidifiers equipped with backflow preventers.¹ Running condensate to an indirect drain is yours. A new drain line, or a new tap on the house water supply inside Denver, reads like Plumbing A's "potable water supply piping and appliances connected thereto," so ask the inspector before you cut in.⁴
• Boilers and hydronic heat. Hot Water or Steam and Hot Water license, as above. A boiler in a commercial building, or in an apartment house of six or more units, also falls under the state boiler inspection program.²⁴
• Framing and finishes. Cutting joists or building a chase for ductwork is building work under a Denver building license.⁴
• Old insulation. Boiler pipe wrap and old duct wrap can be asbestos. Disturb more than 50 linear feet on pipes, or 32 square feet on other surfaces, in a single-family home and Colorado wants a certified asbestos inspection first, with friable material removed by a certified abatement contractor.²⁶

Federal rules every HVAC company meets

EPA Section 608. "Any person servicing, installing or disposing of stationary appliances (except the disposal of small appliances) must be a section 608 certified technician." The supply house has to check that you are, or employ, a certified technician before it sells you refrigerant, and an office person can buy on the company account with a copy of the tech's card. Apprentices are exempt only while "closely and continually supervised by a certified technician." The cards don't expire.²⁸

A2L refrigerants (R-454B, R-32). New residential and light commercial air conditioning and heat pump systems have to use a refrigerant with a global warming potential of 700 or less, from January 1, 2025. EPA's May 2026 rule removed the installation deadline for systems whose parts were made or imported before 2025, so older R-410A stock can still go in. It also kept the rule that lets you replace a failed condensing unit on an existing system: "a homeowner can choose to replace their failed condensing unit rather than purchase a whole new system."²⁹ Denver's 2025 mechanical code sends A2L systems to ASHRAE 15-2024.⁷ Its A2L policy adjusts the limits for altitude: an R-32 refrigerant concentration limit of 4.2 pounds per 1,000 cubic feet and 4 pounds for R-454B. It also wants refrigerant type and charge on commercial and multifamily drawings, plus a contractor's or engineer's declaration before final inspection where leak mitigation is used or a system holds 55 pounds or more.¹⁰ The Pikes Peak region still enforces the 2021 mechanical code, so ask its inspectors what they want on an A2L install.¹⁴

Lead paint. Colorado doesn't run its own renovation program, so EPA's rule applies. Disturb more than 6 square feet of painted surface in a room (20 outside) in a home built before 1978, say cutting a return or a new register into plaster, and the firm needs EPA lead-safe certification. That covers "all firms, even sole proprietorships."³⁰

Apprentices, journeymen and who can work alone

Denver has no apprentice ratio for mechanical work, and I found no rule that your techs hold a Denver certificate. The code puts the weight on the supervisor instead: Denver's requirement is "that a supervisor of record perform on site supervision of all work performed," and a company "may employ multiple certified supervisors" to meet it.⁷ Denver does issue journeyman certificates in heating and ventilating, refrigeration, gas service and steamfitting ($40 for three years), and a holder "may perform this work only in the employ of" the matching contractor.^{5, 6}

Other places differ. Aurora exempts journeymen, apprentices and trainees working for a licensed company, "provided that the work is performed under the supervision of a certified supervisor."¹⁵ The Pikes Peak region licenses the workers: a Heating Mechanic IV for HVAC service techs and a Heating Mechanic I for gas fitting, $10 a year each. An unlicensed helper there works "under the immediate and direct supervision" of a licensed mechanic who is "physically on the job site at all times."¹⁴ And whatever the city, anyone who connects gauges or adds refrigerant needs a 608 card or close supervision by someone who has one.²⁸

Denver HVAC permits: what needs one and who inspects

Denver inspects its own work. Permits go to the licensed contractor, or to a homeowner on their own single-family home.^{7, 11} The repair rule is the one to know: "No mechanical permit shall be required for all general repairs and replacements of like units unless the work involves disconnection and reconnection of" a natural gas line (except replacing a gas valve), a flue vent, a refrigerant line, a steam or hot water line, or safety controls on high-pressure boilers.⁷ That catches every furnace swap, every split-system change-out and every boiler. A tune-up, a capacitor or a blower motor doesn't need one.

Most house jobs are quick permits, issued online without plan review. The mechanical list for houses and duplexes includes "Residential A/C," compressor units, ductwork, evaporative coolers, exhaust systems, gas fireplaces, forced air heating, gas piping, make-up air units, range hoods, rooftop units of 10 tons or less, unit heaters, ventilating systems and water heaters. The boiler and A/C list adds boilers, baseboard, radiant heat and piping.⁸ Some things can't go on a quick permit: walk-in coolers and freezers, chillers inside a building, cooling towers and oil burner systems need engineer-stamped plans. On new houses and additions, Denver wants the builder's Residential Construction Permit issued before it gives you a trade permit. A condenser on the outside of a landmark or a house in a historic district also goes through Landmark Preservation review.⁸

Commercial replacements and the electrification rule

Denver's energy code adds a step when you replace a gas furnace, a condensing unit or a gas rooftop unit in a commercial or multifamily building. The applicant picks one of three: an electrification feasibility report on a heat pump, a sizing report, or a gas test of all the piping on the meter.⁷ Since September 15, 2026, Denver lets one-for-one replacements of 300 MBH or less, gas-to-heat-pump swaps included, go on a quick permit with no submittal. Bigger units go to Express Review with one of those three documents. An emergency replacement of a single failed unit of the same capacity is exempt.⁹ A new or replacement indoor gas furnace in an existing commercial building must also be low-NOx or at least 90 percent AFUE.⁷

Three permit rules that catch new contractors

• Permit before work. Denver doubles the fee for work started without a permit, with a $100 minimum, and adds an investigation fee of the same amount.⁷ For emergency work, like a dead furnace in January, the double fee is waived if you apply "within 3 normal working days after commencement of the emergency work."⁷
• The homeowner exemption is the owner's. Denver's homeowner permits cover owner-occupied single-family homes only, after an exam for mechanical work. A helper "cannot accept payment," and "A licensed Denver contractor may not serve as a designated worker."^{7, 11}
• The furnace has to be legal to sell. Check the NOx rating or the Energy Star listing on any new gas furnace before you quote it.²³

Xcel Energy and the gas meter

In Denver the gas utility is Xcel Energy. "The meter may be set if an approved city or county inspection has been received," and "For all gas meters, only Xcel Energy may unlock or operate the inlet valve." Where the meter has an outlet valve, "authorized heating contractors or gas inspectors may operate the gas meter outlet valve (a), only after meeting the appropriate installation and inspection requirements." Meter questions go to Xcel's Builders Call Line, 800-628-2121.³¹

Outside Denver: Aurora, Colorado Springs, Lakewood, Boulder and Fort Collins

Most HVAC firms on our Colorado list are based outside Denver, from Parker and Elizabeth up to Mead and La Salle. Your Denver license does nothing in those towns. Each big jurisdiction runs its own:

Anywhere else, call the building department before you quote and ask three things: do you license or register mechanical contractors, what insurance certificate do you want, and who may run gas pipe.

Can I take this job? A table for Denver HVAC contractors

The verdicts assume a Denver Heating Ventilating Air Conditioning (Residential Only) license and a house or duplex in Denver, unless the row says otherwise. "Sub it out" means another licensed contractor pulls its own permit for that part.

Your first 30 days: the checklist

This is the whole checklist. The printable version is the same list laid out to tick off, with blanks for the numbers.

A. License and supervisor, week 1

1. Look up the company license on Denver's licensee search, write down the class and the expiration date, and add it to your e-permits account. Licenses run three years; renew from 30 days before the date, never work after it.^{6, 7}
2. Check the class against the work you'll sell. Splits on commercial jobs need Refrigeration A; boilers need Hot Water or Steam and Hot Water; anything over 5 tons, or in a building other than a house, duplex or townhouse, is outside the residential license.⁴
3. Supervisor: certificate number and expiration date on file, the Supervisor Statement of Responsibility signed, and a letter on letterhead if they aren't an owner. They work for no other contractor. If they leave, Denver hears within 3 working days and you have 30 working days to replace them.^{6, 7}
4. Name, address and entity: report a name or address change within 15 days; a new entity needs a new license within 30 days.^{6, 7}
5. Supervisors carry their certificate on the job.⁷

B. Business, insurance and tax

6. Company formed and current with the Colorado Secretary of State, under the exact name on your license and insurance.^{6, 14}
7. General liability of at least $1,000,000 per occurrence and $2,000,000 aggregate.⁴
8. Workers' compensation of at least $100,000 per occurrence and $250,000 aggregate, or a filed rejection of coverage if you have no employees. With one employee, family and part-time included, the policy is required.^{4, 21}
9. Bond: none required for mechanical work in Denver or the cities above.
10. Sales tax: if you sell furnaces and air conditioners, get a state sales tax license, collect tax on the equipment and list labor separately. Ask your accountant how your contracts are written before you decide.²²
11. Denver Treasury: Occupational Privilege Tax. The business pays $4 a month for each owner or partner and each employee earning $500 or more a month in Denver, and withholds another $5.75 a month from each of those employees. It applies "regardless of whether a permanent location is maintained in Denver." Open a use tax account too for materials used on Denver jobs: Denver "does not collect use tax at the time a building permit is issued."¹³

C. The cities you'll work in

12. Aurora: mechanical systems contractor license and supervisor license.¹⁵
13. Colorado Springs and El Paso County: Pikes Peak mechanical license, insurance certificate first, Heating Mechanic licenses for your techs. Allow 6 to 8 weeks.¹⁴
14. Lakewood: Class C mechanical registration.¹⁶
15. Boulder and Fort Collins: city mechanical or HVAC license, city named on the insurance certificate; Fort Collins also wants a business license.^{17, 18}
16. Any other town: call before you quote.

D. Refrigerant, equipment and lead

17. EPA 608 cards for everyone who touches refrigerant, with copies on file for the supply house account.²⁸
18. Gas furnaces you stock or quote: NOx rating of 14 ng/J or less, or Energy Star certified.²³
19. A2L equipment: read the installation manual's room size and leak sensor rules; in Denver use the altitude-adjusted limits.¹⁰
20. Pre-1978 homes: EPA lead-safe firm certification and a certified renovator before you cut into painted surfaces.³⁰

E. Subs, gas and utilities

21. An electrician lined up for every condenser, mini-split and heat pump circuit, and a plumber for water heaters and gas lines in state-inspected counties.^{1, 9}
22. Xcel Energy's Builders Call Line saved: 800-628-2121. Only Xcel operates the meter inlet valve.³¹
23. Your license number on quotes, contracts and invoices so customers can look you up. I found no Colorado or Denver rule requiring HVAC license numbers on trucks or ads, unlike Colorado plumbers.

F. Renewals and the heat pump credit

24. Renewal dates in the calendar with a 60-day reminder: Denver license and supervisor certificate (three years each), Pikes Peak and Aurora (yearly), Lakewood, Boulder and Fort Collins, insurance, workers' comp.^{6, 14, 15}
25. If you'll install heat pumps: apply to become a registered contractor for the state heat pump tax credit. December 31, 2026 is "the final date to apply" for installs completed in 2026.²⁷

What happens if you cross the line

Working without a license or a permit

• Denver's penalties. Breaking the building code carries the city's general penalty: a fine of up to $999, up to 300 days in jail, or both, and "each day an offense and violation continues shall constitute a separate offense."^{7, 12} Work without a permit pays a double fee plus an investigation fee, the violation can be recorded against the property, and Denver can suspend or revoke a license for up to three years, with no reapplying for up to five after a revocation.⁷
• Other trades' work. Wiring or plumbing without the state license is a class 2 misdemeanor: up to 120 days in jail, a $750 fine, or both.²
• A furnace that fails the NOx limit. The attorney general can seek up to $2,000 per violation.²³
• The customer can sue. Failing "to obtain all governmental licenses or permits required to perform the services" is a deceptive trade practice in Colorado: actual damages or $500, three times damages for bad faith, plus attorney fees. The state can also seek up to $20,000 per violation, or $50,000 when the customer is elderly.³²

Getting paid

Colorado's courts hold that a contract needing a license you don't have creates "no right of action which a court of justice will enforce," and a contractor without required licenses and permits "cannot recover compensation for its services."^{33, 35} One 1956 case is an HVAC story. An unlicensed plumber sued over a $2,750 job of plumbing fixtures and a furnace in a new house. The Colorado Supreme Court let him collect for the furnace because "Plaintiff did not need a license from any authority to furnish and install the furnace, stoker, pipes and ducts incident thereto," and not for the plumbing labor.³⁴ Today Denver licenses that furnace work, so the same split could cut against you: the part inside your license is collectable, the part outside it may not be.

Insurance

I found no Colorado rule on what unlicensed or unpermitted work does to your own policy. The state's permit page warns homeowners that their insurance "may not cover the costs of repair for the work performed by anyone without liability insurance who causes damage to your home."¹⁹ Your policy wording decides your side, so ask your agent in writing whether you're covered for work done without a required permit or outside your license class, and keep the reply.

More for new HVAC contractors

• HVAC pricing guide: what to charge for a service call, your labor rate and the first jobs, with a free rate sheet.
• HVAC tune-up checklist: the visit in order, the target readings and what to charge, with a free report card.
• Opening a supply house account: what to bring, cash or credit, and how dealer programs work, with a free checklist.
• Quoting your first system replacement: the price, the scope and what the quote must include, with a free proposal template.
• Starting an HVAC business while still employed: side work, your boss's customers, non-competes and when to go.
• Register every install: maker deadlines, your labor warranty and what a callback costs, with a free close-out sheet.
• Your first slow season: the customer list and the one reminder that fills a calendar, with a free log.

Where Deepsel fits

Deepsel is the field service software I build, and it doesn't know Colorado's HVAC rules. It won't pull a permit, track your license, certificate or insurance dates, check a furnace's NOx rating or file a heat pump credit. It has no field for a license number either. Here's what it does help with. The invoice footer you set once is copied onto every invoice, so your Denver license number and city licenses go on all of them. The shop-wide terms text is copied onto every quote under "Terms," a good place for "permit included" and who does the electrical. You can build a checklist template once in Settings, say for a furnace change-out (NOx-compliant model, permit number, electrician's permit, gas test, flue, combustion readings, inspection passed), and add it to each quote; it stays internal, and every tick records who checked it and when. Equipment records hold brand, model, serial, year, filter size, tonnage, refrigerant, SEER2 or AFUE, and a nameplate photo. One limit for heat pump jobs: line items can't go below zero, so Deepsel can't print the "State of Colorado Heat Pump Discount" as its own minus line, and the Energy Office wants that discount shown separately on the invoice. Quotes can carry options, customers approve and sign on screen, and an optional card deposit is credited on the final invoice. Free covers 30 estimates and 30 invoices a month for your whole team; Pro is $29 a month with unlimited estimates and invoices (pricing). If you send invoices from a template today, the HVAC invoice template has a license number line, and the HVAC installation checklist covers the commissioning side of a change-out.

Frequently asked questions

Does Colorado require an HVAC license?

Not from the state. Colorado licenses electricians and plumbers and has no license for heating, ventilating, air conditioning or refrigeration contractors. Cities and counties license HVAC work instead: Denver through its mechanical licenses (a supervisor certificate first, then a contractor license), the Pikes Peak Regional Building Department for Colorado Springs and El Paso County, and Aurora, Lakewood, Boulder and Fort Collins through their own licenses or registrations. The state still reaches HVAC work through gas piping permits, the electrical license for line-voltage wiring, workers' compensation, sales tax and a 2026 emissions limit on new gas furnaces.

How do I get a Denver HVAC license?

It's two steps. First someone in the company gets a Denver supervisor certificate for the work: six years' experience and the ICC residential mechanical exam (F32) for the residential classes, eight years and the master mechanical exam (F29) for Heating and Ventilating Class A and Refrigeration Class A, shown with notarized letters from employers or customers. Then the company applies for the contractor license in e-permits with the Supervisor Statement of Responsibility and its Secretary of State documents. Review takes about 14 to 20 business days. Each mechanical license type costs $250 for three years, and the certificate $60.

Can you work HVAC without a license in Colorado?

As an employee of a licensed contractor, usually yes in Denver and Aurora, where the license sits with the company and its supervisor. In the Pikes Peak region the code also licenses the workers (Heating Mechanic IV for service techs, Heating Mechanic I for gas fitting), and unlicensed helpers work with a licensed mechanic on site. Anyone who handles refrigerant needs EPA Section 608 certification. Contracting HVAC work yourself without the local license is a different story: in Denver it carries fines of up to $999 a day and jail time, and you may not be able to collect for the work.

What HVAC certification do I need in Colorado?

EPA Section 608 certification for anyone who services, installs or disposes of equipment containing refrigerant, and to buy refrigerant. Colorado has no state HVAC technician certificate. Local credentials are ICC exams: Denver's supervisor certificates use the F32 residential mechanical or F29 master mechanical exam, Aurora wants the master mechanical contractor certification, and Fort Collins the G29. Denver also issues journeyman certificates.

Do I need a plumbing license to run gas lines in Colorado?

Inside Denver, no: gas piping is in every Denver heating license (HVAC Residential Only, Heating and Ventilating A and B, Hot Water, Steam and Hot Water and Gas Service), so you pull the mechanical permit. Most big cities put gas piping in their mechanical licenses too. In areas the state inspects, the plumbing law says only a master plumber of a registered plumbing contractor, or a homeowner, may apply for a gas piping permit, even though the state's own form still lists a gas pipe installer. Ask the State Plumbing Board before you run new gas pipe there, or sub it to a registered plumbing contractor.

Does my Denver HVAC license work in Aurora or Colorado Springs?

No. Each city licenses on its own and none of them accepts Denver's license. Aurora needs its mechanical systems contractor license (ICC master mechanical certification), Colorado Springs and El Paso County need a Pikes Peak Regional Building Department mechanical license, Lakewood a Class C mechanical registration, Boulder a city mechanical license and Fort Collins its own HVAC license. Denver does say it may accept another jurisdiction's exam results as part of a full application.

What insurance does a Denver HVAC contractor need?

Denver's license policy sets general liability of at least $1 million per occurrence and $2 million aggregate, and workers' compensation of $100,000 per occurrence and $250,000 aggregate, or a filed rejection of coverage if you have no employees. The Pikes Peak Regional Building Department and Boulder also want $1 million and $2 million, with themselves named on the certificate. None of them requires a bond for mechanical work.

Which gas furnaces can I still sell in Colorado?

Ones that meet Colorado's nitrogen oxide limit. Since January 1, 2026, a new fan-type central furnace under 175,000 Btu an hour can't be sold or offered for sale in Colorado unless it emits no more than 14 nanograms of NOx per joule. Energy Star certified furnaces count as compliant, units already in Colorado inventory on that date are exempt, and propane furnaces are exempt until 2031. Check the spec sheet for the NOx rating before you quote any gas furnace.

How do I look up a Colorado HVAC license?

There's no state HVAC license, so there's no state lookup. Search Denver licenses in Denver's e-permits licensee search, and use the Pikes Peak Regional Building Department's and Aurora's contractor lookups for those areas. The state's DORA lookup covers the electricians and plumbers you sub work to.

How much do HVAC techs make in Colorado?

The Bureau of Labor Statistics puts the May 2025 median for heating, air conditioning and refrigeration mechanics and installers at $31.35 an hour ($65,200 a year) in Colorado, and $34.41 an hour in the Denver-Aurora-Centennial metro area. That's employee pay, so as an owner treat it as the floor your own hour has to cover before overhead, vehicle, insurance and profit.

Sources

1. Colorado Revised Statutes title 12: 12-115-103(5) (electrical work), 12-115-116(9) (appliance vendors may connect an appliance where no new wiring of the structure is needed), (15)(a) (environmental controls), (16)(a) (class 2 and 3 circuits); 12-155-103(2) (gas piping, excluding appliances installed on existing service connections) and (8) (plumbing), 12-155-118(6)(a) (no plumbing license or permit for heating appliances and systems, air conditioning installations and humidifiers, including related water piping and indirect waste piping), 12-155-120(1)(c) and (11) (plumbing and gas piping permits; qualified applicant), 12-155-121. Title 12 has no HVAC licensing article. olls.info, Colorado Revised Statutes 2026, read November 3, 2026.
2. C.R.S. 12-20-407(1)(a) (practicing as an electrician or plumber without a license is a class 2 misdemeanor), olls.info title 12; C.R.S. 18-1.3-501(1)(a.5) (up to 120 days, up to $750, or both), olls.info title 18. Read November 3, 2026.
3. Colorado Department of Regulatory Agencies, "Home & Repair" ("Not all occupations are licensed, such as roofers and general contractors"). dora.colorado.gov, read November 3, 2026.
4. Denver Community Planning and Development, building permit policy 25-DCBC 120A, "Classification of Licenses, Registrations and Certificates" (Gas Service; Heating and Ventilating Class A and B; Heating Ventilating Air Conditioning, Residential Only; Hot Water; Refrigeration Class A and B; Steam and Hot Water; Boilermaker; Plumbing Registration Class A; certificates required for each license; insurance coverage requirements). denvergov.org, read November 3, 2026.
5. City and County of Denver, "Mechanical Certificates" (scope of work, minimum experience and ICC exams for each certificate; notarized letters; review, payment and renewal). denvergov.org, read November 3, 2026.
6. City and County of Denver, Contractor Licensing: Contractor Licenses (two-step process; renewal window), Apply for a Contractor's License (Supervisor Statement of Responsibility; Supervisor of Record letter; Secretary of State documents; 14 to 20 business days; each license type paid separately), Supervisor's Statement of Responsibility, Contractor License Application (changes within 15 days; new legal entity within 30 days), Contractor Licensing Fees (all mechanical license types $250 every 3 years; supervisor certificate $60; journeyman certificate $40). All read November 3, 2026.
7. City and County of Denver, 2025 Denver Building Code: Administration 107.3 and 107.4.1 (penalties; recorded notice), 121.1 to 121.3 (contractor, certified supervisor employed by one contractor, licenses required for permitted work), 122.2 to 122.4 (exams; other jurisdictions' certificates; supervisor leaves: 3 working days to notify, 30 to replace; on-site supervision of all work), 125 (renewal every 3 years; changes; new entity), 126.1 and 126.3 (permits before work; licensed subcontractors; insurance per policy; carry the certificate), 127.1 and 127.4 (discipline, including allowing a license to be used by another person; up to three years), 130.3.1 (mechanical repair exemption and its limits), 131.4 (homeowner permits; designated worker), 138.2 and 138.3 (double fees, $100 minimum, emergency exception; investigation fee); 2025 Denver Mechanical Code 1101.1.1 and chapter 15 (A2L refrigerants and ASHRAE 15-2024); 2025 Denver Energy Code definitions, C503.3.2 (low-NOx or 90 AFUE furnaces) and C503.3.3 (partial electrification for space heating). denvergov.org, read November 3, 2026.
8. City and County of Denver, "Quick Permits" (boiler and A/C, mechanical and electrical lists for houses and duplexes; items that need plans; Residential Construction Permit first on new houses and additions; Landmark review). denvergov.org, read November 3, 2026.
9. City and County of Denver, "Commercial Building Equipment Replacement Guide," revised September 14, 2026 (residential installs need mechanical and electrical quick permits; commercial quick permits to 300 MBH; Express Review options; emergency replacement; electrical contractor pulls the reconnection permit). denvergov.org, read November 3, 2026.
10. City and County of Denver, building permit policy 25-DMC Chapter 11, "A2L refrigerants: Regulations, Submittal Requirements, and Interpretations," revised August 3, 2026 (ASHRAE 15-2024; altitude-adjusted limits for R-32 and R-454B; submittals; contractor or engineer declaration). denvergov.org, read November 3, 2026.
11. City and County of Denver, "Applying for Permits as a Homeowner" (single-family homes only; exam before mechanical/HVAC work; designated worker can't be paid). denvergov.org, read November 3, 2026.
12. Denver Revised Municipal Code § 1-13, "General penalty" (up to $999, up to 300 days, or both; each day a separate offense). library.municode.com, read November 3, 2026.
13. Denver Department of Finance, Treasury: Tax Guide Topic 61, "Occupational Privilege Taxes," PDF; "General Contractors and Subcontractors - Construction within Denver," PDF. Both read November 3, 2026.
14. Pikes Peak Regional Building Department: License Types (mechanical contractors A to E; Heating Mechanic I and IV), Licensing FAQ (6 to 8 weeks; no reciprocity; RBC201.7 insurance certificate and workers' comp), Insurance Requirements ($1,000,000/$2,000,000; named insured must match; 10-day cancellation clause), Mechanical Contractor License Application ($50 application fee; $100 license; exam; three references), Code Changes (2023 Pikes Peak Regional Building Code, 2nd printing, from June 30, 2026; 2021 mechanical and fuel gas codes), 2023 Pikes Peak Regional Building Code, 2nd printing (RBC201 examinee employed by only one contractor; RBC201.9 30-day grace; Table RBC202.6 annual fees; RBC204 mechanical licenses, mechanics and helpers). All read November 3, 2026.
15. City of Aurora: Contractor Licensing and Lookup; "Contractor License Fees & Requirements" (Form A105, revised 02/2026: mechanical systems contractor, ICC Master Mechanical Contractor certification, $131 and $164) and "Application for License" (Form A135, revised 10/2024), linked from that page; Aurora City Code 22-91 (mechanical systems contractor), 22-95 (licenses required; annual fee), 22-96 (supervisor; personal supervision; 5 business days to notify, 15 days to replace), 22-97 (journeymen, apprentices and trainees), 22-98 (changes; new entity within 15 days), 22-100, 22-101. All read November 3, 2026.
16. City of Lakewood, "Contractor Registration" (Class C Mechanical; $150 first year, $400 three-year renewal) and the Contractor Registration information sheet. lakewoodco.gov, read November 3, 2026.
17. City of Boulder, "Contractor Licensing" (mechanical contractor classes A to E; ICC certification; annual fees; $1,000,000 / $2,000,000 general liability, City of Boulder additional insured; no reciprocal licenses). bouldercolorado.gov, read November 3, 2026.
18. City of Fort Collins, "Contractor Licensing" (HVAC(R), HVAC(C), HVAC(RR), Refrigeration and Gas Piping licenses; ICC G29; fees; business license; $2,000,000 general aggregate). fcgov.com, read November 3, 2026.
19. Colorado Division of Professions and Occupations, "Colorado Electrical and Plumbing Permits Homepage" (local inspection areas; homeowner notice; Fuel Gas Pipe Installer login), dpo.colorado.gov; legacy permit FAQ, dora.state.co.us; "Gas Piping Permit Application" (applicant boxes: plumbing contractor, homeowner, gas pipe installer), PDF. All read November 3, 2026.
20. State Plumbing Board Rules, 3 CCR 720-1, version effective August 14, 2026, rule 1.6(A) (permits for fuel gas piping issued in the name of the qualified applicant or registered contractor performing the work). sos.state.co.us, read November 3, 2026.
21. Colorado Department of Labor and Employment, Division of Workers' Compensation, "Workers' Compensation Insurance Requirements." cdle.colorado.gov, read November 3, 2026.
22. Colorado Department of Revenue, "FYI Sales 6: Contractors and Retailer-Contractors" (furnaces and air conditioners as non-building materials; retailer-contractors need a sales tax license; lump-sum contractors). tax.colorado.gov, read November 3, 2026.
23. C.R.S. 25-7-1502 to 25-7-1507 (emission standards for new water heaters and fan-type central furnaces from January 1, 2026; exemptions; Energy Star; civil penalty up to $2,000 per violation), as amended by SB 26-002 effective August 12, 2026. olls.info; Colorado General Assembly, SB26-002. Both read November 3, 2026.
24. C.R.S. 9-4-104 (boilers in private residences and apartment houses of fewer than six family units exempt), olls.info; Colorado Division of Oil and Public Safety, "Boiler Inspection," ops.colorado.gov. Both read November 3, 2026.
25. Colorado Department of Public Health and Environment, "Hydrofluorocarbons (HFC) Phase-Out" (AQCC Regulation 22, Part B). cdphe.colorado.gov, read November 3, 2026.
26. Colorado Department of Public Health and Environment, "Asbestos support and guidance: Renovation, demolition, and certification" (single-family trigger levels; certified inspector; general abatement contractor). cdphe.colorado.gov, read November 3, 2026.
27. Colorado Energy Office, "Colorado Heat Pump Tax Credits" (registered contractors; 2026 credit and minimum discount amounts; discount shown separately on the invoice; registration deadline December 31, 2026 for 2026 installs). energyoffice.colorado.gov, read November 3, 2026.
28. U.S. EPA, "Section 608 Technician Certification Requirements," epa.gov; "Questions and Answers about the Refrigerant Sales Restriction," epa.gov. Both read November 3, 2026.
29. U.S. EPA, "Technology Transitions HFC Restrictions by Sector," epa.gov; "Phasedown of Hydrofluorocarbons: Reconsideration of Certain Regulatory Requirements Promulgated Under the Technology Transitions Provisions," 91 FR 31284, May 26, 2026, effective July 27, 2026, federalregister.gov. Both read November 3, 2026.
30. U.S. EPA, "Lead Renovation, Repair and Painting Program" (authorized states, Colorado not among them; "all firms, even sole proprietorships"), epa.gov; 40 CFR 745.83 (minor repair and maintenance: 6 sq ft per room inside, 20 sq ft outside), law.cornell.edu. Both read November 3, 2026.
31. Xcel Energy, "Service Guide Colorado: Natural Gas and Electric Installation" (revised April 2022): natural gas inspection requirements and meter unlock process; Builders Call Line 800-628-2121. PDF, read November 3, 2026.
32. Colorado Consumer Protection Act, C.R.S. 6-1-105(1)(z), 6-1-112(1), 6-1-113(2). olls.info, Colorado Revised Statutes 2026, read November 3, 2026.
33. Benham v. Heyde, 122 Colo. 233, 221 P.2d 1078 (Colo. 1950). courtlistener.com, read November 3, 2026.
34. Carter v. Thompkins, 133 Colo. 279, 294 P.2d 265 (Colo. 1956). courtlistener.com, read November 3, 2026.
35. Aspen Drilling Co. v. Hayes, 876 P.2d 86 (Colo. App. 1994). courtlistener.com, read November 3, 2026.
36. U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics, May 2025, heating, air conditioning and refrigeration mechanics and installers (49-9021): Colorado median $31.35 an hour, $65,200 a year; Denver-Aurora-Centennial metro $34.41 an hour (series OEUS080000000000049902108, OEUS080000000000049902113, OEUM001974000000049902108, via the BLS public data API). bls.gov, read November 3, 2026.