Home addition cost in Billings, MT
Local estimate from BLS wage data and BEA price levels. Reviewed Nov 4, 2026.
- Typical range (300 sq ft)
- $38,700 – $78,400
- Per sq ft
- $128 – $255
- before permit
- Versus US midpoint
- +2%
- US $57,500
- Rank of 300 metros
- #98
- 1 = most expensive
A home addition in Billings, MT usually costs $38,700 to $78,400 for 300 sq ft. That works out to about $128 to $255 per sq ft before permits. That is within a few percent of the national midpoint, so there is little local premium or discount. Carpenters earn a median of $28.34 an hour in the Billings area, 3% below the US median of $29.12.
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Estimated cost for 300 sq ft in Billings, MT, standard level
$50,600 to $66,500
About $166 to $217 per sq ft before permits. Labor is about 68% of the bill.
| Part | Low | High |
|---|---|---|
| Materials | $15,000 | $19,600 |
| Labor | $34,800 | $45,500 |
| Permits and fees | $890 | $1,450 |
| Total | $50,600 | $66,500 |
Cost breakdown for 300 sq ft in Billings, MT
| Part of the job | Low | Midpoint | High | Share |
|---|---|---|---|---|
| Materials | $11,500 | $17,300 | $23,000 | 30% |
| Labor | $26,700 | $40,100 | $53,500 | 68% |
| Permits and fees | $470 | $1,150 | $1,850 | 2% |
| Total | $38,700 | $58,600 | $78,400 | 100% |
What is behind the Billings number
The wage side of the estimate leans on carpenters, who do 50% of the hours on a typical job. Their local median is $28.34 an hour. Add the other trades involved and the blended wage index for Billings is 1.05 (US = 1.00), which puts labor at 68% of the total.
Materials are scaled with BEA's regional price parity for goods. Billings is at 96.0 against 100 for the US, so a materials line of $18,000 nationally becomes $17,300 here (midpoint, 300 sq ft). Permits follow the all-items index of 93.5: $470 to $1,850.
Data note: 10% of the labor weighting for this project uses a statewide median because BLS has no published metro figure for that trade in Billings. The wage table below marks each row.
How Billings compares
Contractors rarely work more than an hour or two from home, so the neighboring metros set a rough ceiling and floor for your quotes. Midpoints for 300 sq ft range from $50,300 to $60,500 across Billings and its five closest metros.
| Area | Range | Midpoint | vs. here |
|---|---|---|---|
| Billings, MTthis page | $38,700 – $78,400 | $58,600 | |
| Bozeman, MT115 miles | $40,000 – $81,000 | $60,500 | +3% |
| Idaho Falls, ID225 miles | $34,500 – $69,900 | $52,200 | −11% |
| Missoula, MT275 miles | $38,300 – $77,500 | $57,900 | −1% |
| Logan, UT300 miles | $33,700 – $68,400 | $51,100 | −13% |
| Rapid City, SD305 miles | $33,200 – $67,300 | $50,300 | −14% |
| Montana (statewide) | $38,700 – $78,400 | $58,600 | level |
| United States | $38,000 – $77,000 | $57,500 | −2% |
Out of the 300 metros we cover, Billings ranks #98 for the cost of this job (#1 is the most expensive). Statewide, Billings is 0% below the Montana figure.
Elsewhere in Montana
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Bozeman, MT | 72,210 jobs | $40,000 – $81,000 | $60,500 | +3% |
| Missoula, MT | 67,070 jobs | $38,300 – $77,500 | $57,900 | −1% |
Metros of a similar size
Big cities and small ones price differently, so here is Billings against the 4 metros with the closest total employment.
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Barnstable, MA | 94,110 jobs | $42,400 – $85,800 | $64,100 | +10% |
| Iowa City, IA | 93,760 jobs | $34,100 – $69,000 | $51,600 | −12% |
| Macon, GA | 95,030 jobs | $31,500 – $63,800 | $47,600 | −19% |
| Oshkosh, WI | 93,750 jobs | $44,700 – $90,300 | $67,500 | +15% |
Specs and site conditions that change a Billings bid
Type of addition
A new room is $125-$250 per sq ft; a bump-out $85-$200; an attic conversion $50-$150; a garage conversion $50-$200 (HomeGuide).
Plumbing and fixtures
Adding a bathroom or kitchen drives the price up the most.
Permits
Construction permits run $500-$2,000, or $5-$21 per $1,000 of project cost (HomeGuide).
What nearby projects cost in Billings
Jobs that often go together with home addition are priced below at their usual sizes, using the same Billings wage and price inputs. Compared with national midpoints, bathroom remodel comes out highest (+5%) and roof replacement lowest (−4%); the gap comes from the trades each job uses.
| Project | Size | Range | vs. US |
|---|---|---|---|
| Kitchen remodel | 120 sq ft | $18,200 – $31,000 | −2% |
| Bathroom remodel | 45 sq ft | $4,900 – $24,400 | +5% |
| Detached garage | 576 sq ft | $28,900 – $57,900 | level |
| Roof replacement | 2,000 sq ft of roof | $5,850 – $11,900 | −4% |
Pick a size, pick a tier: home addition pricing in Billings
The cited range is split into basic, standard and premium bands, then scaled to Billings. Bands overlap, because plenty of standard jobs cost as much as a light premium one. Sizes run from bump-out (100 sq ft) to large suite (600 sq ft).
Basic
$38,700 to $54,600
Bump-out or simple room without plumbing
Standard
$50,600 to $66,500
Standard room addition with HVAC and electrical
Premium
$62,500 to $78,400
Large addition with bath or kitchen and a new foundation
| Size | Basic | Standard | Premium |
|---|---|---|---|
| bump-out (100 sq ft) | $13,200 – $18,900 | $17,500 – $23,100 | $21,700 – $27,400 |
| 20x20 room (400 sq ft) | $51,500 – $72,400 | $67,200 – $88,200 | $82,900 – $104,000 |
| large suite (600 sq ft) | $77,000 – $108,000 | $100,500 – $131,500 | $123,500 – $155,000 |
Billings weather and the home addition calendar
Climate numbers on this page come from NOAA's 1991-2020 U.S. Climate Normals at the nearest suitable station, Billings Logan Intl Ap (in the city). They are 30-year averages, so any one year can run hotter, colder or wetter.
For digging, grading and setting material in the ground, the comfortable months in Billings are April through October: 7 of 12. Outside them, January, February, March, November and December have an average overnight low at or below freezing (32°F).
In January, February, March, November and December the average low is at or below freezing, which means frozen ground and slower digging, compaction and sod or stone placement. NOAA counts about 142 days a year with a low at or below 32°F at this station.
Billings gets about 14 inches of precipitation in a normal year, including roughly 57 inches of snow. The wettest months are April, May and June (2.4 inches in May). Inside the workable window, July and August are the driest, at 1.2 and 0.9 inches. The station averages about 32 days a year at 90°F or above.
We do not adjust the estimate by month, because we have no reliable published data on seasonal pricing. It is still worth asking contractors whether an off-peak start date changes their bid.
| Month | Avg high °F | Avg low °F | Precip (in) | For this job |
|---|---|---|---|---|
| Jan | 36 | 18 | 0.6 | Cold |
| Feb | 39 | 20 | 0.6 | Cold |
| Mar | 49 | 27 | 0.9 | Cold |
| Apr | 57 | 35 | 1.7 | Workable |
| May | 67 | 44 | 2.4 | Workable |
| Jun | 77 | 52 | 2.2 | Workable |
| Jul | 87 | 59 | 1.2 | Workable |
| Aug | 86 | 58 | 0.9 | Workable |
| Sep | 74 | 49 | 1.4 | Workable |
| Oct | 59 | 37 | 1.4 | Workable |
| Nov | 46 | 27 | 0.6 | Cold |
| Dec | 36 | 19 | 0.6 | Cold |
What local crews earn in Billings
The labor line is built from BLS wage data, one trade at a time. This job draws on 6 trades. We compare each trade's local median with the US median, weight the ratios by how much of the job each trade does, and apply the blend to the national labor cost. For Billings the blend is 1.05.
Carpenters (47-2031), 50% of the weighting: a median of $28.34 an hour, in line with the US median of $29.12. The middle half of them earn between $23.84 and $30.83 an hour. About 530 work in the metro. That is 56.5 per 10,000 jobs, compared with 43.1 nationally, which suggests plenty of local crews to bid.
Cement masons and concrete finishers (47-2051), 10% of the weighting: a median of $30.12 an hour, 10% above the US median of $27.41. The middle half of them earn between $27.69 and $33.63 an hour. About 140 work in the metro. That is 14.9 per 10,000 jobs, compared with 13.3 nationally, so the supply of crews looks typical.
For electricians (47-2111, weighted 10%) the local median is $38.93 an hour, which is 28% above the national $30.38. The middle half of them earn between $30.62 and $40.14 an hour. BLS counts 510 of them working in the area, 54.4 for every 10,000 jobs (US: 48.7), so the local bench is about average.
Plumbers, pipefitters and steamfitters (47-2152), 10% of the weighting: a median of $39.27 an hour, 28% above the US median of $30.67. The middle half of them earn between $31.39 and $45.37 an hour. About 360 work in the metro. That is 38.4 per 10,000 jobs, compared with 30.0 nationally, which suggests plenty of local crews to bid.
Drywall and ceiling tile installers (47-2081) carry 10% of the labor weighting. BLS does not publish this trade for the Billings metro, so we used the Montana statewide median: $28.92 an hour against $28.33 for the US. The middle half of them earn between $23.34 and $31.63 an hour.
Roofers (47-2181), 10% of the weighting: a median of $24.99 an hour, 6% below the US median of $26.65. The middle half of them earn between $23.09 and $31.76 an hour. About 80 work in the metro. That is 8.5 per 10,000 jobs, compared with 8.7 nationally, so the supply of crews looks typical.
A quick sensitivity check: moving the lead trade (carpenters) from the median to the 75th percentile wage adds about $1,650 to the midpoint estimate; the 25th percentile takes off about $2,950. That is a swing of roughly 5.0% to 2.8% of the total, which is useful for judging whether a bid reflects wages or something else, such as scope or margin.
Billings has 93,800 jobs in total (BLS, May 2025), ranking 213th by size among the 300 metros on this site.
| Trade | Weight | 25th pct | Median | 75th pct | US median | Ratio | Level used |
|---|---|---|---|---|---|---|---|
| Carpenters (47-2031) | 50% | $23.84 | $28.34 | $30.83 | $29.12 | 0.97 | metro |
| Cement masons and concrete finishers (47-2051) | 10% | $27.69 | $30.12 | $33.63 | $27.41 | 1.10 | metro |
| Electricians (47-2111) | 10% | $30.62 | $38.93 | $40.14 | $30.38 | 1.28 | metro |
| Plumbers, pipefitters and steamfitters (47-2152) | 10% | $31.39 | $39.27 | $45.37 | $30.67 | 1.28 | metro |
| Drywall and ceiling tile installers (47-2081) | 10% | $23.34 | $28.92 | $31.63 | $28.33 | 1.02 | state |
| Roofers (47-2181) | 10% | $23.09 | $24.99 | $31.76 | $26.65 | 0.94 | metro |
| Blended | 100% | 1.05 | |||||
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Home addition in Billings: your questions
+How much does it cost to build a home addition in Billings?
For 300 sq ft, expect $38,700 to $78,400 in the Billings area. A standard-spec job lands at $50,600 to $66,500. Small jobs usually cost more per sq ft and large ones less.
+What is the price per sq ft for home addition in Billings?
About $128 to $255 per sq ft for materials and labor, plus $470 to $1,850 for the permit if one is needed. The US range is $125 to $250.
+Is home addition cheaper in Billings or Bozeman?
Bozeman is 115 miles away. The midpoint for 300 sq ft there is $60,500, which is 3% more than Billings ($58,600). Wage and materials indexes both feed that gap.
+How much of the bill is labor in Billings?
About 68% at the midpoint, or $40,100 out of $58,600. Materials are 30% and permits 2%. Nationally, labor is 67%.
+What would 20x20 room (400 sq ft) cost in Billings?
$51,500 to $104,000. Pick a different size in the estimator above to get your own number.
+Does home addition need a permit in Billings?
Often, but rules are set by your city or county building office, so call before you hire. Budget $470 to $1,850 for fees in the Billings area (our national range of $500 to $2,000 scaled by the local price level).
+Is Billings expensive for home addition compared with the rest of Montana?
Billings is 0% below the Montana statewide estimate ($58,600 at the midpoint). We cover 3 metros in Montana; see the state page to compare them.
+What do carpenters earn in Billings?
The BLS median is $28.34 an hour in the Billings area, compared with $29.12 nationally. The 25th to 75th percentile range is $23.84 to $30.83.
+What do basic and premium home addition work cost in Billings?
For 300 sq ft, basic work runs $38,700 to $54,600 and premium work $62,500 to $78,400. Basic means: bump-out or simple room without plumbing. Premium means: large addition with bath or kitchen and a new foundation.
+When is the best time to build a home addition in Billings?
Based on NOAA 1991-2020 normals, the comfortable months for this kind of work are April through October. July and August are typically the driest of those months. Local contractors' schedules matter as much as the weather, so book early for the busy months.
Home addition near Billings
Where these numbers come from
Base prices are national ranges from the sources below. We scale labor by local BLS wages, materials by BEA goods prices and permits by the BEA all-items price level. Full method on the methodology page.
- HomeGuide: How Much Does a Home Addition Cost? (2026) (accessed November 4, 2026)
- Cost to Renovate: Renovation Labor Report 2026: Where the Money Goes (accessed November 4, 2026)
- HomeGuide: 2026 Building Permit Costs | Fees & Cost Calculator (accessed November 4, 2026)
- BLS Occupational Employment and Wage Statistics, May 2025
- BEA Regional Price Parities, 2024
- NOAA NCEI U.S. Climate Normals, 1991-2020
Note on derived figures: Materials = 32% of the installed price, from Cost to Renovate's mid-range 'Structural' category split (56% labor, 32% materials, 11% permits and design). It is a category average rather than an addition-specific figure.