The County rule
Community Planning & Permitting (CP&P) issues permits only for unincorporated Boulder County; "If your property is inside a city or town, contact that city or town directly" (Building Permits, read 26 October 2026). For heating and cooling the County keeps a short list. From its EZ BP page and the exemption list in publication B05:
| Job | Permit in unincorporated Boulder County? |
|---|---|
| Air conditioning | Yes, EZ BP |
| Furnace | Yes, EZ BP |
| Mechanical heat pump or mini split | Yes, EZ BP |
| Gas line | Yes, EZ BP |
| Water heater, boiler, evaporative cooler | Yes, EZ BP |
| Portable heater, portable cooling unit, portable evaporative cooler | No (B05) |
| "Replacement of any part that does not alter approval of equipment or make such equipment unsafe" | No (B05) |
| Self-contained refrigeration with 10 lb of refrigerant or less, or motors of 1 hp or less | No (B05) |
B05 adds that an emergency replacement can go in first, but "the permit application shall be submitted within the next working business day to the building official."
Who can pull it
The County licenses its own contractors (Contractor Licensing, read 26 October 2026): a contractor is "anyone who engages in any type of work for compensation for which a building permit is required". The property owner, and "A person who is performing labor or repair work on their own property", are not contractors under that definition. "Plumbers and electricians are licensed by the State of Colorado", so the circuit for a heat pump is a state-licensed electrician's job.
| County license | Covers | Fee |
|---|---|---|
| Residential Mechanical | "Residential mechanical installations and repair" | $175 |
| Commercial Mechanical | "Commercial mechanical installations and repair" | $200 |
A license needs a passed ICC exam (or a license from another Colorado jurisdiction that uses one), liability and workers' compensation insurance, and lasts three years. A Denver or City of Boulder mechanical license alone is not a County license; ask for the County one.
What it costs
The B33 fee page (read 26 October 2026) adds up five lines. The zoning and public health review fee "does not apply to EZBP permits", which leaves four:
| B33 line | How it is figured |
|---|---|
| Building permit fee | $89.24 for the first $2,000 plus $15.35 per further $1,000, for jobs from $2,000 to $25,000 |
| Plan check fee | 65% of the building permit fee |
| County use taxes | Half the valuation times 13 rates, 1.335% combined |
| Technology fee | $8 for an EZ BP |
Worked out from those lines (our arithmetic, rounded to whole dollars as B33 directs):
| Job value | Permit fee | Plan check | Use tax | Tech fee | Total |
|---|---|---|---|---|---|
| $8,000 furnace | $181 | $118 | $53 | $8 | $360 |
| $11,000 system | $227 | $148 | $73 | $8 | $456 |
| $16,000 heat pump | $304 | $198 | $107 | $8 | $617 |
Valuation is the higher of the County's own figure and the contract price. B33 says building materials bought in Boulder County are exempt from County taxes "when you present your building permit to the materials vendor". The County's fee estimator prints a PDF estimate; staff set the final fee at approval.
How to apply and get it inspected
- Confirm the address is unincorporated. A Boulder mailing address is not enough; Niwot, Gold Hill, Ward and the county islands are County, the City of Boulder is not.
- Apply online. CP&P's online permits page needs an account to apply or pay. EZ BP questions go to ezbp@bouldercounty.gov or 303-441-3926.
- Inspections. Requests made before 3:30 p.m. Monday to Thursday are eligible for next-business-day scheduling, by Accela, by phone at 303-441-3925, or by texting "SCHEDULE" to 877-558-7966 (Building Inspections). You need the permit number, which starts with "BP".
- Expiry. A County permit lapses if work does not start within 180 days of issue or stops for 180 days.
- Check the result. Permit and inspection records are public in the County's Accela search; you do not need an account to view them.
What 1,917 County HVAC permits show
| Measure | Unincorporated Boulder County HVAC |
|---|---|
| Permits on homes, May 2023 to April 2026 | 1,917 |
| Firms | 177 |
| Firms with a permit, May 2025 to April 2026 | 105 |
| Usual filed value | $11,058 |
| Middle half of firms' usual value (3+ permits) | $7,965 to $16,221 |
| Complete or closed (permits a year or more old) | 66.6% |
| Usual days from issue to completion | 50 |
| Firms with 10+ permits under 70% complete | 20 of 33 |
| 10th / 90th-percentile busy firm | 35.4% / 89.0% |
| Share of permits held by the five busiest firms | 44.8% |
| Busiest / quietest month (index, 100 = average) | August (126) / March (69) |
Closing the permit is where County HVAC firms differ most. Only 66.6% of permits a year or more old were complete, and 20 of the 33 firms with 10 or more permits were under 70%; the 10th-percentile firm sat at 35.4% and the 90th at 89.0%. The five busiest firms hold 44.8% of the work, so a handful of names will come up in any set of quotes. Filing peaks in August and is quietest in March, which is the month to book a change-out if yours can wait. Prices by job size: Boulder County HVAC cost.
See every Boulder County HVAC contractor by permits completed →
Related
Compare firms on the Boulder County HVAC list; counts by month are on Boulder County permit statistics and timing on how long a Boulder County permit takes. Inside the City of Boulder the rules differ: Boulder HVAC permit. Other places: do I need a permit for HVAC replacement. National prices: HVAC replacement cost; what to ask: hiring an HVAC contractor.
What this does not tell you
Our file is the County's Accela permit feed, which stopped taking new applications on 4 May 2026, so it ends with April 2026 and permits issued since are not in it. "Complete" is the County's complete or closed status, not a separate final-inspection field. The County publishes no bulk license file, so we show no license status; ask for the County license number and look it up in Accela.
How we know this
The EZ BP list, exemptions, fee lines, license classes and fees, inspection scheduling and expiry are quoted from Boulder County's EZ BP, Building Permits, B05, B33, Contractor Licensing, Building Inspections and online permits pages, read 26 October 2026; the fee examples are our arithmetic. Counts are Boulder County Community Planning & Permitting HVAC permits on homes in the unincorporated county, May 2023 to April 2026; "complete" uses permits a year or more old and days are the median from issue to the County's completion date.
Numbers come from Boulder County Community Planning & Permitting building permits on homes in unincorporated Boulder County (the County's Accela permit layer, which stopped taking new applications on May 4, 2026, so the data ends with April 2026; the City of Boulder and the other cities issue their own permits), with issue dates and declared job values from the Boulder County Assessor's permit file, data through October 20, 2026. Nobody paid to be on this page and nobody can.
Questions
- Do I need a permit to replace a furnace in unincorporated Boulder County?
Yes. Furnaces, air conditioning, mechanical heat pumps and mini splits are all on the County's EZ BP (Easy Building Permit) list, which is for simple residential projects that do not need plans. Only portable units and like-for-like part replacements are exempt under publication B05.
- How much is an HVAC permit in Boulder County?
The County's B33 fee table charges a building permit fee on the job's valuation, a plan check fee of 65% of that, County use taxes on half the valuation and an $8 EZ BP technology fee. On an $11,000 system that works out to about $456 (our arithmetic); the County's online estimator gives the figure for your job.
- Who can pull an HVAC permit in unincorporated Boulder County?
A contractor holding a Boulder County Residential Mechanical license (or Commercial Mechanical), or the property owner doing their own work. The County licenses contractors for work in the unincorporated county; electrical wiring for the unit needs a Colorado-licensed electrician.
- How long does an HVAC permit take to close in Boulder County?
The usual unincorporated Boulder County HVAC permit in our file was marked complete 50 days after it was issued, and 66.6% of those a year or more old were complete or closed.
- Is the City of Boulder the same as Boulder County for HVAC permits?
No. The City of Boulder, Longmont, Louisville, Lafayette and the other towns issue their own permits and licenses. The County's Community Planning & Permitting department covers unincorporated areas such as Niwot, Gold Hill and the mountain areas, and also reviews and inspects work in Jamestown.
Build your own list
Every firm with that kind of permit on record. Pick what you value. The list moves.
Related guides
- Ames building permit search: how to look up permits on an address
- Do I need an HVAC permit in Ames? Yes: what is exempt, homeowner permits, the $56.23 base fee and inspections
- Do I need an HVAC permit in Anaheim? The mechanical permit for a furnace or AC change-out, fees and inspections
- Do I need an HVAC permit in Arlington, VA? The like-for-like exemption, the gas exception and zoning
- Do I need an HVAC permit in Cincinnati? Yes, to install or replace a furnace or AC: the 2026 fee and the slow final
- Do I need a permit to replace my AC or furnace in Citrus Heights? The rule, the fee basis and the final
For one city
- Home improvement costs in Boulder County, CO (2026): what 10 kinds of jobs were filed at
- Do I need a roofing permit in unincorporated Boulder County? Yes past one square, with a Class A roof and a photo final
- Do I need a solar permit in unincorporated Boulder County? Yes: the B46 plan set, the $400 fee and the engineer's roof letter
- EZ BP Program for Residential Building Permits — Boulder County (accessed 2026-10-26)
- Building Permits — Boulder County (accessed 2026-10-26)
- Building Permit Requirements (B05) — Boulder County (accessed 2026-10-26)
- Permit Fees (B33) — Boulder County (accessed 2026-10-26)
- Contractor Licensing in Unincorporated Boulder County (accessed 2026-10-26)
- Building Inspections — Boulder County (accessed 2026-10-26)
- Community Planning & Permitting Online Permits, Licenses, and Applications — Boulder County (accessed 2026-10-26)
- Boulder County Services Portal (Accela Citizen Access) search (2026-10-26)