Billings, MT
Billings plumbing permit cost
A Billings plumbing permit is a $20.00 issuance fee plus a parts list.
Every row is a count times a price: fixtures $15.00 (water, drainage piping and backflow protection included per fixture), building sewers $7.00, water heaters $5.00, gas piping systems of one to five outlets just $1.00 (+$7.00 per additional outlet), backflow devices $7.00–$15.00 by diameter.
How this fee is calculated
These are the components the schedule defines for this permit, as they applied on 2026-09-28. A component only applies to your project if its conditions match — read that column before assuming a figure. Want a figure for your own project? Estimate this fee with the permit fee calculator.
| Component | Formula | Applies when | Range |
|---|---|---|---|
| Backflow device, 2 inch and smaller — $7.00Permit fee | $7.00 per backflow device | backflow devices over 0 | — |
| Each building sewer or trailer park sewer — $7.00Permit fee | $7.00 per connection | connections over 0 | — |
| Each plumbing fixture or trap (incl. water, drainage, backflow) — $15.00Permit fee | $15.00 per fixture | Fixtures over 0 | — |
| Each gas-piping system of one to five outlets — $1.00Permit fee | $1.00 per gas service line | gas service lines over 0 | — |
| Plumbing permit issuance — $20.00Other fee | $20.00 flat fee | Every permit of this type | — |
| Each water heater and/or vent — $5.00Permit fee | $5.00 per water heater | water heaters over 0 | — |
A real permit fee is these components added together. The department’s final calculation is the one that applies — this is the schedule it will be based on.
A worked example
Follow the arithmetic by hand. Every line is produced by the engine from the rules above, so the total cannot drift away from the schedule behind it.
Worked example
A commercial tenant-finish plumbing scope: 12 fixtures, 1 building sewer, 3 water heaters and 2 backflow devices (2 inch and smaller).
| Input | Value |
|---|---|
| Fixtures | 12 |
| Occupancy class | Commercial |
| Type of work | New construction |
| Number of connections | 1 |
| Number of water heaters | 3 |
| Number of backflow devices | 2 |
Example total
$236.00
An estimate, not an official fee. It is calculated from the published fee schedule as it applied on 2026-09-28. The permit office’s own calculation is the one that applies, and your project may fall under rules this schedule does not describe.
Fee schedule as of 2026-09-28Rules applied 5Rules considered 6
| Component | How it is calculated | Amount |
|---|---|---|
Backflow device, 2 inch and smaller — $7.00Permit fee§ 3.N: For each backflow protective device other than atmospheric-type vacuum breakers, 2 inch diameter and smaller — $7.00 (over 2 inch: $15.00, recorded).Show the working
| $7.00 per backflow device | $14.00 |
Each building sewer or trailer park sewer — $7.00Permit fee§ 3.B: For each building sewer and each trailer park sewer — $7.00.Show the working
| $7.00 per connection | $7.00 |
Each plumbing fixture or trap (incl. water, drainage, backflow) — $15.00Permit fee§ 3.A: For each plumbing fixture or trap or set of fixtures on one trap (including water, drainage piping, and backflow protection) — $15.00.Show the working
| $15.00 per fixture | $180.00 |
Each water heater and/or vent — $5.00Permit fee§ 3.F: For each water heater and/or vent — $5.00.Show the working
| $5.00 per water heater | $15.00 |
Plumbing permit issuance — $20.00Other fee§ 3: For the issuance of each permit — $20.00. (The section's unit rows stack on this issuance fee.)Show the working
| $20.00 flat fee | $20.00 |
| Total | $236.00 |
Fees that do not apply here
Listed so you can see what was considered and left out, rather than wondering whether something is missing. A rule can also be left out because it is not published for this permit at all, and that is stated where it matters.
- Each gas-piping system of one to five outlets — $1.00 — This fee does not apply to the inputs provided.
Assumptions
- Calculated from 5 fee rules in effect on 2026-09-28.
- Amounts are rounded to the nearest cent, once, at the end of each component.
Six lines — $236.00.
Permit issuance: $20.00. Fixtures: 12 × $15.00 = $180.00. Building sewer: 1 × $7.00 = $7.00. Water heaters: 3 × $5.00 = $15.00. Backflow devices: 2 × $7.00 = $14.00.
Total: $20 + $180 + $7 + $15 + $14 = $236.00.
What moves it: each fixture's $15.00 already carries its supply, waste and backflow piping — the separate $7.00 backflow row bills only free-standing devices; and a gas-piping system for the break room would add just $1.00 (one-to-five outlets).
What is different in Billings
The $20.00 issuance is the permit's floor — the cheapest possible plumbing job, one water heater, is $25.00 — and the unit rows stack on it in whatever combination the scope names. The fixture row is deliberately broad: $15.00 covers the fixture's water piping, drainage piping and backflow protection in one line, so the schedule's separate backflow row addresses only free-standing devices not part of a fixture set.
The gas-piping row is the oddity worth knowing: $1.00 covers a whole one-to-five-outlet system, with the $7.00 per-additional-outlet row only engaging beyond five. The 2026 resolution cut these amounts with everything else — the schedule below is the reduced one.
One reading note: the adopted resolution is a scanned PDF whose amount column interleaves in text extraction; each row was matched to its printed amount by word coordinates, and the coordinate dump is in the research file — the prices above are the positional read, not a guess.
What this figure does not include
Impact fees, utility connections and other departments’ permits are the usual omissions, and in some jurisdictions they are larger than the permit fee itself.
Not included in these figures
This is § 3's plumbing permit fee. It excludes:
- The building permit and its 60% commercial plan review — on the building page.
- Unmodelled unit rows — rainwater drains ($25.00 each), cesspools ($40.00), private sewage disposal systems ($7.00), industrial pretreatment interceptors ($7.00), lawn sprinklers ($7.00 per meter), atmospheric vacuum breakers ($5.00 for 1–5, $1.00 each over 5).
- Additional gas outlets beyond five — $7.00 each, recorded in the research file.
- Mechanical permits — the $20.00-minimum equipment list, recorded without their own page.
What you need before applying
- The unit rows include their pipingRequired
§ 3.A's fixture row prices 'each plumbing fixture or trap or set of fixtures on one trap (including water, drainage piping, and backflow protection)' — the $15.00 covers the fixture's supply, waste and backflow in one line, which is why the schedule's separate backflow row addresses only devices NOT included in a fixture set.
Common questions
How much is a plumbing permit in Billings?
$20.00 for issuance plus the unit rows your scope names: $15.00 per fixture, $7.00 per building sewer, $5.00 per water heater, $1.00 per gas system of one to five outlets, $7.00–$15.00 per free-standing backflow device.
Does the fixture fee include piping?
Yes — § 3.A prices each fixture or trap 'including water, drainage piping, and backflow protection,' so one $15.00 line covers the fixture's whole rough-in.
What does a water heater replacement permit cost?
$5.00 for the water heater row plus the $20.00 issuance — $25.00 on a stand-alone permit, the schedule's cheapest realistic job.
How are gas lines permitted?
§ 3.G–H: $1.00 per gas-piping system of one to five outlets, plus $7.00 for each additional outlet beyond five. A typical residential system with four drops is one dollar.
Is there a minimum plumbing permit fee?
Yes — the $20.00 issuance applies to every permit, so the smallest permit (a single water heater) is $25.00 and the floor is $20.00 for any scope with no unit rows at all.
How long is a Billings plumbing permit good for?
The resolution's inspection apparatus applies: inspections are scheduled through the Building Division, and reinspection bills at the $75.00/hour rate of § 6 when work is called before it is ready.
Source and verification
The documents behind every figure on this page, with the dates that make them checkable.
- OrdinanceCityPrimary source
Read 2026-09-26. The adopted PDF (7 pp.) is an image-only scan; its page 1 was read visually in the browser and matches the Gazette's published text-layer draft of the same resolution word for word (identical whereas clauses, building bands, and the 60% commercial plan-review line). The draft's text layer is the amount source: § 1's consolidated eight-band building ladder (chaining exactly at every seam from $45.00 to a $9,529.00 base), the 60% commercial plan review, § 2's residential electrical flats and five-band commercial project-cost ladder, § 3's $20.00 plumbing issuance plus unit rows (read out of the scan by word coordinates), § 4's mechanical rows and § 5's fire-system bands. Adoption (APPROVED 11-0) verified on the February 23, 2026 council agenda; the Gazette reports the operational go-live 'on or after March 2'.
Verification
Last verified against the official source in Sep 2026.