Skip to main content
PermitBase

Mechanical / HVAC Permit in Billings, Montana

Required for heating, ventilation, air conditioning, and related mechanical installations in Billings, governed by the 2021 International Mechanical Code (IMC) and International Fuel Gas Code (IFGC) as adopted by the City of Billings. Billings is a Montana DLI-certified jurisdiction for mechanical permitting.

Verified 2026-07-02 · Source

When you need this permit

  • Mechanical permit required for installation or relocation of furnaces, boilers, compressors, air handling units, ventilation systems, and appliance vents
  • Governed by the 2021 IMC and 2021 IFGC as adopted by City of Billings (Administrative Order #150)
  • Minimum permit issuance fee of $15.00 plus per-unit fees based on appliance type and capacity
  • Apply through the CityView Portal

Required documents

Check off what you have — your progress is saved on this device.

Not ready yet0 of 1 required documents checked.

This checker covers one permit. A full project usually triggers several — our checklist will assemble all of them, free →

Fee schedule

Permit Issuance (minimum per permit)City of Billings Mechanical Permit Fees schedule
$15.00
Forced-air gravity-type furnace or burner, up to and including 100,000 Btu/hCity of Billings Mechanical Permit Fees schedule
$9.00
Forced-air gravity-type furnace or burner, over 100,000 Btu/hCity of Billings Mechanical Permit Fees schedule
$11.00
Floor furnace, including ventCity of Billings Mechanical Permit Fees schedule
$9.00
Suspended heater, recessed wall heater, or floor-mounted unit heaterCity of Billings Mechanical Permit Fees schedule
$9.00
Appliance vent installed and not included in an appliance permitCity of Billings Mechanical Permit Fees schedule
$4.50
Repair, alteration, or addition to heating/cooling/refrigeration/absorption appliance or systemCity of Billings Mechanical Permit Fees schedule
$9.00
Air handling unit up to and including 10,000 cfm, including attached ductsCity of Billings Mechanical Permit Fees schedule
$6.50
Air handling unit over 10,000 cfmCity of Billings Mechanical Permit Fees schedule
$11.00
Evaporative cooler other than portable typeCity of Billings Mechanical Permit Fees schedule
$6.50
Ventilation fan connected to a single ductCity of Billings Mechanical Permit Fees schedule
$4.50
Ventilation system not part of any authorized heating/air conditioning systemCity of Billings Mechanical Permit Fees schedule
$6.50
Hood served by mechanical exhaust, including ductsCity of Billings Mechanical Permit Fees schedule
$6.50
Domestic-type incineratorCity of Billings Mechanical Permit Fees schedule
$11.00
Commercial or industrial-type incineratorCity of Billings Mechanical Permit Fees schedule
$45.00
Appliance or equipment not classed in other categories / no other listed feeCity of Billings Mechanical Permit Fees schedule
$6.50
Other Inspections and FeesCity of Billings Mechanical Permit Fees schedule
$45.00 minimum, or total hourly City cost if greater

Review timeline

Plan reviewTypical estimate — confirm current times with the Billings building department
~4–7 business days

How long did your Mechanical / HVAC Permit permit actually take in Billings?

Anonymous — one question, no email. Answers are combined and only shown once at least 5 people have reported.

Inspection process

  1. 1

    Rough-In

    Ductwork and mechanical equipment rough-in before walls closed; gas piping pressure test before concealment

  2. 2

    Final

    Equipment operational; kitchen/bathroom exhaust vents verified; gas appliance shutoff valve within 6 feet; combustion air and clearances verified

See the full Billings inspection guide — scheduling & re-inspection fees →

Tips

  • A typical furnace replacement (up to 100,000 Btu/h) costs $15.00 issuance + $9.00 for the appliance = $24.00 minimum.
  • Billings is a Montana DLI-certified jurisdiction for mechanical permitting within city limits.
  • Dryer vent runs over 35 feet require a permanent label and manufacturer installation instructions per IMC 504.6.5, verified at mechanical rough inspection.

Frequently asked questions

Billings requires a mechanical / hvac permit for: Mechanical permit required for installation or relocation of furnaces, boilers, compressors, air handling units, ventilation systems, and appliance vents; Governed by the 2021 IMC and 2021 IFGC as adopted by City of Billings (Administrative Order #150); Minimum permit issuance fee of $15.00 plus per-unit fees based on appliance type and capacity; Apply through the CityView Portal. If your project isn't listed, confirm with City of Billings Building Division at (406) 657-8270 before starting work.

The mechanical permit issuance fee is $15.00, plus $9.00 for a forced-air furnace up to 100,000 Btu/h (or $11.00 if over 100,000 Btu/h), per the City of Billings Mechanical Permit Fees schedule.

Plan review for a mechanical / hvac permit in Billings typically runs 4–7 business days. This is an estimate, not a published figure — confirm current review times with City of Billings Building Division at (406) 657-8270.

You'll need: Mechanical Permit Application. See the required-documents checklist on this page for details on each.

Billings requires 2 inspection(s) for a mechanical / hvac permit, in order: Rough-In, Final. Schedule each through City of Billings Building Division ((406) 657-8270).

Apply through City of Billings Building Division at 316 N 26th St, 5th Floor, Billings, MT 59101. Phone: (406) 657-8270, email: permits@billingsmt.gov. Office hours: Building Division front counter, 5th Floor, City Hall, 316 N. 26th St., Billings, MT 59101 (inspection requests: inspections@billingsmt.gov or 406-657-8270). Official information: https://www.billingsmt.gov/67/Building.

Billings, Montana has adopted: Montana has a mandatory statewide building code administered by the Montana Department of Labor & Industry (DLI) Building Codes Bureau, amended by the Administrative Rules of Montana (ARM) Title 24, Chapter 301. Cities, counties, and towns may become 'certified' to locally administer permitting and inspection for all or part of the code (building, plumbing, electrical, mechanical, swimming pool, etc.); a certified local program's adopted code 'may include only codes adopted by the Building Codes Bureau' (ARM 24.301.202). Non-certified areas fall under direct state administration by the DLI Building Codes Bureau. Source: Montana DLI Building Codes Bureau, Certified City, County and Town Programs and Current Codes pages (bsd.dli.mt.gov/building-codes-permits).; Billings is a Montana DLI-certified jurisdiction for Building (B), Plumbing — Mechanical/Gas (P(M/G)), Electrical (E), Mechanical (M), and Swimming Pool (SP) within Billings city limits; certified program contact on file with DLI: Jessica Fust, (406) 657-8270. Source: Montana DLI Building Codes Bureau, Current Codes page (list of certified jurisdictions), bsd.dli.mt.gov/building-codes-permits/current-codes; 2021 International Building Code (IBC) — effective statewide June 11, 2022; adopted by City of Billings, last readopted September 1, 2022 per Administrative Order #150; 2021 International Residential Code (IRC) — effective statewide June 11, 2022; adopted by City of Billings per Administrative Order #150. Note: per the City's Adopted Codes page, IRC Chapters 11-14 and 16-43 are deleted in their entirety; IRC Chapter 15 (Exhaust Systems) is adopted as an alternative to the IMC for exhaust systems only, with all other mechanical-system requirements for detached 1-2 family dwellings and townhouses (3 stories or less) found in the adopted IMC; 2021 International Existing Building Code (IEBC) — effective statewide June 11, 2022; 2021 International Mechanical Code (IMC) — effective statewide June 11, 2022; adopted by City of Billings per Administrative Order #150; 2021 International Fuel Gas Code (IFGC) — effective statewide June 11, 2022; adopted by City of Billings per Administrative Order #150; 2021 International Energy Conservation Code (IECC) — effective statewide June 11, 2022; adopted by City of Billings per Administrative Order #150; 2021 Uniform Plumbing Code (UPC) — effective statewide June 11, 2022; adopted by City of Billings per Administrative Order #150 (Montana uses the Uniform Plumbing Code, not the International Plumbing Code); 2020 National Electrical Code (NEC) — effective statewide June 11, 2022; adopted by City of Billings per Administrative Order #150; 2021 International Swimming Pool and Spa Code (ISPSC) — effective statewide June 11, 2022; Billings is DLI-certified for swimming pool (SP) permitting; 2021 International Fire Code (IFC) — per City of Billings Building Division FAQ, current adopted code list; ICC A117.1-2017 Accessibility — effective statewide June 11, 2022 (state-adopted; referenced for commercial accessibility compliance); NFPA 99c, Standard on Gas and Vacuum Systems (medical gas), 2021 Edition — per City of Billings Adopted Codes page; All codes amended by the Administrative Rules of Montana (ARM) Title 24, Chapter 301. City of Billings Building Codes were last (re)adopted September 1, 2022 per Administrative Order #150. Local amendments apply — see the Billings overview page for the full list.

Sources & verification

Verified against official sources. Last reviewed 2026-07-02.

Fees, timelines, and adopted codes are researched from each jurisdiction's published records — see how we verify. Requirements change and vary by project, so always confirm the current details with the Billings building department before you submit. PermitBase is an independent reference and is not affiliated with any government agency.