Do I need a permit for radon mitigation in Montana?

In most Montana jurisdictions, yes — anything structural or system-related needs one, and the rules are set locally, not statewide. Check the specific city notes below for how your building department handles it.

How much does a radon mitigation permit cost in Montana?

Fees scale with job valuation. On a $945 – $2,625 project the permit and plan review are usually a small percentage of the total, and your contractor should list them as a line item rather than burying them.

What happens if work is done without a permit?

Unpermitted work can mean stop-work orders, double fees to retro-permit, forced removal of finished work, denied insurance claims, and problems when you sell the home.

Does the contractor need a Montana license too?

Yes for most trade work. Verify the license number with the Montana licensing board and confirm the classification actually covers radon mitigation.

How long does permit approval take?

Over-the-counter permits can be same-day; anything needing plan review commonly takes one to four weeks, and longer in historic districts or HOAs. Build that into your schedule.

Who schedules the inspections?

Your contractor normally schedules them, but you should ask for the inspection dates and results in writing at each milestone.

Cost guides/Radon Mitigation/Montana permits

Permits & licensing

Radon Mitigation permits in Montana

What Montana building departments require for radon mitigation, what it adds to a $945 – $2,625 project, and how the rules differ across 4 cities we track in the state.

Get a permit-inclusive estimate Radon Mitigation price guide

The Montana permit process, step by step

Confirm whether your scope is permitted work

In Montana, structural, electrical, plumbing, mechanical and most exterior envelope work on radon mitigation projects triggers a permit. Cosmetic, like-for-like repairs often do not.

Let the licensed contractor pull it

A contractor who asks you to pull an owner-builder permit is shifting liability to you. Whoever pulls the permit is responsible for code compliance.

Budget for fees and plan review

Permit fees are usually a percentage of job valuation plus a flat plan-review fee. On a typical Montana radon mitigation project of $945 – $2,625, expect permitting to be a low single-digit percentage of the total.

Schedule inspections before you close things up

Rough-in inspections have to happen before drywall, backfill or roofing covers the work. A missed inspection can mean tearing finished work back out.

Keep the final sign-off

The closed permit and certificate of completion belong in your home file — buyers, appraisers and insurers all ask for them on permitted work.

City-by-city permit notes

City	Local permit note	Typical project
Billings	Most Billings, MT projects that change structure, electrical, plumbing or mechanical systems need a permit from the local building department; cosmetic work usually does not.	$918 – $2,550
Missoula	Most Missoula, MT projects that change structure, electrical, plumbing or mechanical systems need a permit from the local building department; cosmetic work usually does not.	$954 – $2,650
Great Falls	Most Great Falls, MT projects that change structure, electrical, plumbing or mechanical systems need a permit from the local building department; cosmetic work usually does not.	$891 – $2,475
Bozeman	Most Bozeman, MT projects that change structure, electrical, plumbing or mechanical systems need a permit from the local building department; cosmetic work usually does not.	$1,008 – $2,800

Radon Mitigation permit FAQs for Montana

Permit requirements are set locally and change. Confirm details with your city or county building department before starting work. Typical statewide project value used here: $1,785.

Keep researching in Montana

All Montana price guides Radon Mitigation near me Best radon mitigation in Billings Best radon mitigation in Missoula Best radon mitigation in Great Falls Best radon mitigation in Bozeman