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Residential Addition / Remodel / Alteration Permit in Billings, Montana

Required for additions, remodels, and structural alterations to existing one- and two-family dwellings in Billings, including decks, garages, and interior remodels affecting structural or life-safety elements. Reviewed against the 2021 IRC as adopted by the City of Billings. Apply through the CityView Portal.

Verified 2026-07-02 · Source

When you need this permit

  • Building permit required for additions, remodels, and alterations affecting structural, fire, or life-safety elements
  • Attached/detached garages: use the City of Billings Attached/Detached Garage Submittal Workbook
  • Decks: use the City of Billings Deck Submittal Workbook (for single-level, attached or detached, square or rectangular decks only; multi-level or non-rectangular decks require design-professional or structural-engineer-stamped plans)
  • A site plan showing lot lines, setbacks from all property lines, and existing/proposed structures is required
  • Stairs require a concrete landing as wide as the stairs and 36 inches in the direction of travel; stairs with 4 or more risers require a handrail; decks 30 inches or more above grade require guarding
  • Plans must comply with City of Billings Design Criteria (30 psf snow load, 110 mph wind, 42-inch frost depth)

Required documents

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Fee schedule

Building Permit Fee — valuation-based (same schedule as new construction)City of Billings Building Permit Fees schedule
$30.00 minimum ($1-$1,000 valuation), scaling up per the Residential and Commercial Building Permit Fees table (e.g., $45.00 for first $2,000 plus $9.00 per additional $1,000 up to $25,000)
Other Inspections and Fees (re-inspection, after-hours, unlisted inspection, extra plan review)City of Billings Building Permit Fees schedule
$45.00 minimum, or total hourly City cost if greater

Review timeline

Plan reviewBillings’s published plan-review target
4–7 business days

How long did your Residential Addition / Remodel / Alteration 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

    Footing/Foundation

    Required before concrete pour for deck posts, garage foundations, or addition footings

  2. 2

    Framing

    Structural framing, connections to existing structure, guardrails and handrails per plan

  3. 3

    Final

    All work complete per approved plans; deck/patio structures reviewed for code compliance at final

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

Tips

  • The Deck Submittal Workbook is only suitable for single-level, square or rectangular attached or detached decks; multi-level decks or decks with hot tubs/enclosed structures require structural-engineer-stamped plans.
  • Decks 30 inches or more above grade require guarding; stairs with 4+ risers require a handrail.
  • Setbacks are typically 5 feet but vary by zoning district — check with City-County Planning at (406) 657-8247 before finalizing a site plan.
  • Call 811 before digging to locate underground utility lines.

Frequently asked questions

Yes. Use the City of Billings Deck Submittal Workbook for a single-level, square or rectangular attached or detached deck. Multi-level decks or decks with hot tubs require structural-engineer-stamped plans submitted for review.

In Billings, the published Building Permit Fee — valuation-based (same schedule as new construction) is: $30.00 minimum ($1-$1,000 valuation), scaling up per the Residential and Commercial Building Permit Fees table (e.g., $45.00 for first $2,000 plus $9.00 per additional $1,000 up to $25,000). Additional published fees: Other Inspections and Fees (re-inspection, after-hours, unlisted inspection, extra plan review) — $45.00 minimum, or total hourly City cost if greater. These are the jurisdiction's own published figures — see the fee schedule table and source citations on this page.

Billings's published plan-review target for a residential addition / remodel / alteration permit is 4–7 business days.

You'll need: Building Permit Application; Construction Drawings. Depending on your project, Billings may also ask for: Deck Submittal Workbook; Attached/Detached Garage Submittal Workbook. See the required-documents checklist on this page for details on each.

Billings requires 3 inspection(s) for a residential addition / remodel / alteration permit, in order: Footing/Foundation, Framing, 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.