Standby Generator permit in Montana

A permanently installed standby generator with automatic transfer switch and fuel connection. Here is the Montana-specific rule: who issues it, typical fees, timeline, go / no-go, and the official source to verify.

Verify locally. Montana adopts the 2021 IRC (ARM 24.301.154) but MCA 50-60-102 exempts residential buildings with fewer than five dwelling units from the STATE building permit unless the local government has certified a building-code program. Billings, Missoula and about three dozen other cities (plus six counties) enforce locally; much of rural Montana has no structural building-permit requirement for single-family homes. State electrical (NEC), plumbing (UPC) and mechanical permits are required statewide regardless of location. Verify with your city building department or the MT DLI Building Codes Program. Rules below are Montana-level guidance drawn from official sources — always confirm with the issuing building department before starting work. See the county permit authorities to find the right office.

Standby Generator permit in Montana

The Montana rule for a standby generator, with fee range, timeline, go / no-go, and the official source.

Montana
Standby Generator

Exact permit fees are set by the local building department. WikEst shows the published or code-based range where one exists, linked to its official source — verify the final amount at the source before budgeting.

Standby Generator permit fee in Montana

ConditionalGenerally allowedcity authority
Permit fee range
Mechanical/electrical permit; fee set by the issuing authority.
Typical timeline
Varies
Setback
Exempt if
Not size-exempt

Exempt criteria: A small portable generator used temporarily is exempt; a permanently installed standby generator with a transfer switch and fixed fuel line requires permits.

A permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply.

Representative cities for Montana: Billings, Missoula.

All 20 project fee ranges in Montana

Official-source ranges where published; “By local jurisdiction” means no flat fee is published and the amount is set case by case.

ProjectPermit?AuthorityFee rangeGo / no-go
🏠 Accessory Dwelling Unit (ADU)conditionalcityWhere a certified city/county enforces, fees follow that jurisdiction; in non-certified areas a single-family home is exempt from the state building permit (trade permits still apply). Verify locally.case-by-case
🪵 Deck / PorchconditionalcityWhere enforced, fees follow the local schedule; verify locally.allowed
🧱 Fence / WallconditionalcityWhere enforced, fencing permits apply above local height limits; verify locally.allowed
🛖 Shed / OutbuildingconditionalcityWhere enforced, small detached sheds may be exempt; verify locally.allowed
🪜 Basement FinishconditionalcityWhere a certified city enforces, a building permit fee applies; in non-certified areas the state building permit is exempt for single-family homes (trade permits still apply). Verify locally.allowed
🚗 Garage / CarportconditionalcityWhere enforced, attached garages (additions) are permitted; verify locally.allowed
☀️ Rooftop Solar PVyesstateElectrical permit required statewide by the MT DLI Building Codes Program (NEC); local jurisdictions may also be involved.allowed
🌡️ HVAC ReplacementyesstateMechanical permit required statewide by the MT DLI Building Codes Program; licensed contractors perform the work.allowed
🍳 Kitchen RemodelconditionalcityWhere enforced, a building permit plus trade permits apply; verify locally.allowed
🛁 Bathroom RemodelconditionalcityWhere enforced, a building permit plus trade permits apply; verify locally.allowed
🏗️ Room AdditionconditionalcityWhere a certified city enforces, a building permit based on valuation applies; in non-certified areas the state building permit is exempt for single-family homes (trade permits still apply). Verify locally.allowed
🪟 Window / Door ReplacementconditionalcityWhere enforced, a permit fee applies if enlarging the opening; in-kind swap often exempt. Verify locally.allowed
🏘️ Roof ReplacementconditionalcityWhere enforced, an in-kind re-roof may be exempt; structural deck replacement requires a permit. Verify locally.allowed
🅿️ Driveway / Parking PadconditionalcityNo building permit for private flatwork where enforced; a right-of-way permit may be needed. Verify locally.allowed
🏊 Swimming Pool / SpaconditionalcityWhere enforced, a building permit plus barrier fencing applies; verify locally.allowed
🧱 Retaining WallconditionalcityWhere enforced, a permit applies if over 4 ft; verify locally.allowed
💥 Demolition / TeardownyescityDemolition permit fee set by the issuing authority; verify locally.allowed
🚰 Septic SystemyescountySeptic permit fee set by the local environmental/health authority; engineered systems cost more.allowed
🔌 EV ChargerconditionalcityElectrical permit; fee set by the issuing authority.allowed
Standby GeneratorconditionalcityMechanical/electrical permit; fee set by the issuing authority.allowed

Montana rule at a glance

Needs permit
conditional
Issuing authority
city
Typical fee
Mechanical/electrical permit; fee set by the issuing authority.
Typical timeline
Varies
Setback
Exempt if
Not size-exempt
A permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply.

Frequently asked questions

Does a standby generator need a permit in Montana?

In Montana, a standby generator is conditional / size-dependent. Issuance is at the city level. Confirm the exact threshold with the local building department using the sources on this page.

Who issues the standby generator permit in Montana?

Montana permits for this project are handled at the city level — usually the city or county building department. Use the county permit authority lookup to find the exact office for your property.

How much does a standby generator permit cost in Montana?

Fees are set locally in Montana and are not a single statewide number. Open the official authority link on this page for the current schedule.

What exemptions apply to a standby generator in Montana?

Baseline exemptions (e.g. small detached structures, low decks) may apply but Montana or your city can amend them. Verify with the local building department.

Standby Generator in other states

StatePermit?AuthorityTypical feeTimelineGo / No-GoKey notes
CaliforniaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify setback and fuel-line rules with the city building department.
TexasPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
FloridaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
New YorkPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
PennsylvaniaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the municipality (e.g., Philadelphia L&I).
IllinoisPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the municipality (e.g., Chicago DOB).
OhioPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the municipality (e.g., Columbus BZS).
GeorgiaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department (e.g., Atlanta Office of Buildings).
North CarolinaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the municipality.
MichiganPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the municipality (e.g., Detroit or Grand Rapids).
New JerseyPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the local Construction Code Official.
VirginiaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
WashingtonPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
ArizonaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the issuing city.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify setback and fuel-line rules with the city building department.
MassachusettsConditionalcityMechanical and/or electrical permit fee set by the city.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (NEC Articles 445/702) covering the transfer switch, gas/propane line, and connection. Verify with your local building department.
TennesseePermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
IndianaConditionalcityMechanical and/or electrical permit fee set by the local building department.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (NEC Articles 445/702) covering the transfer switch, gas/propane line, and connection. Verify with your local building department.
MissouriPermit requiredcityElectrical (and gas, if fuel-fired) permit fee set locally by the municipality.Varies by municipality — electrical/mechanical permits often same-day to 2 weeks.Generally allowedA standby generator requires an electrical permit; fuel-fired units also need a gas/mechanical permit. Review NEC Art. 445 (Generators) and Art. 702 (Legally Required Standby Systems); verify load calc, transfer switch, and placement with your city.
MarylandConditionalcityMechanical and/or electrical permit fee set by the city.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (NEC Articles 445/702) covering the transfer switch, gas/propane line, and connection. Verify with your local building department.
WisconsinPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the municipality; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the municipal building inspection department.
AlaskaConditionalcityMechanical/electrical permit; fee set by the municipality.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement. Cold-climate starting provisions are reviewed.
AlabamaConditionalcityMechanical/electrical permit; fee set by the city.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
ArkansasConditionalcityValuation-based; Little Rock minimum building-permit fee $50 (work over $5,000 or requiring inspection).Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
ColoradoConditionalcityMechanical/electrical permit; fee set by the city/county.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement. Mountain/WUI communities may add fire-safety siting rules.
ConnecticutConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
DelawarePermit requiredcountyElectrical (and often mechanical/gas) permit fee set by the county (unincorporated) or city.Generally allowedA permanently installed standby generator with a transfer switch and fuel (gas/propane) line requires electrical and often mechanical/gas permits, plus inspection. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify setback and fuel-line rules with the county/city building department.
HawaiiConditionalcountyMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
IowaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
IdahoConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
KansasConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
KentuckyConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
LouisianaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
MainePermit requiredcityElectrical (and gas, if fuel-fired) permit fee set by the municipality.Electrical/mechanical permits often issued same-day to 2 weeks.Generally allowedA standby generator requires an electrical permit; fuel-fired units also need a gas/mechanical permit and combustion/venting review. Maine requires licensed electricians and plumbers. Review NEC Art. 445 (Generators) and Art. 702 (Legally Required Standby Systems); verify placement, load calc, and transfer-switch wiring with the local inspector.
MinnesotaPermit requiredcityElectrical (and gas, if fuel-fired) permit fee set by the municipality.Electrical/mechanical permits often issued same-day to 2 weeks.Generally allowedA standby generator requires an electrical permit; fuel-fired units also need a mechanical/gas permit. Review NEC Art. 445 (Generators) and Art. 702 (Legally Required Standby Systems); verify load calculation, transfer-switch wiring, and placement with your municipal building department.
MississippiConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply.
North DakotaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply.
NebraskaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply.
New HampshireConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
New MexicoConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
NevadaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
OklahomaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
OregonConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
Rhode IslandConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
South CarolinaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
South DakotaConditionalcityMechanical/electrical permit; fee set by the issuing authority.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line). Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
UtahPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
VermontConditionalcityMechanical/electrical permit; fee set by the issuing authority where enforced.Generally allowedA permanently installed standby generator requires mechanical and electrical permits (transfer switch, fuel gas/propane line) where enforced. Setback, carbon-monoxide ventilation, and noise rules apply; some HOAs restrict generator placement.
West VirginiaPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context). Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
WyomingPermit requiredcityElectrical (and often mechanical/gas) permit fee set by the city where enforced; verify locally.Generally allowedA permanently installed standby generator with a transfer switch and fuel (natural gas/propane) line requires electrical and often mechanical/gas permits, plus inspection (NEC Art. 445/702 context) where a building department enforces. Setback, noise, and carbon-monoxide rules may apply, and HOAs may restrict installation. Verify with the city building department.
The WikEst Editorial Team · Updated 2026-08-15
Compiled and reviewed by the WikEst editorial team from official state and municipal building-department publications.

Related tools from our network

A focused set of free calculators and guides across related topics — no account required.