Per diem · MT · GSA FY2027 from October 1, 2026
Per diem rates in Montana, FY2027
Three of Montana's 4 GSA areas follow a summer calendar that keeps September at the peak price.
GSA FY2027 ZIP file published · rates checked · Published by Radif Partners · Rules and data
Federal per diem for the trip
$787
Big Sky / West Yellowstone/Gardiner, MT · Sun, Oct 25 to Wed, Oct 28
| Lodging, 3 nights at the GSA maximum | $507 |
| M&IE before meal deductions | $280 |
| M&IE paid | $280 |
| Total | $787 |
Rates of fiscal year 2027 (October 1, 2026 to September 30, 2027). How this is calculated.
Day by day
| Day | Lodging | M&IE rate | Share | Meals off | M&IE paid |
|---|---|---|---|---|---|
| Sun, Oct 25 FY2027 | $169 | $80 | 75% | – | $60 |
| Mon, Oct 26 FY2027 | $169 | $80 | 100% | – | $80 |
| Tue, Oct 27 FY2027 | $169 | $80 | 100% | – | $80 |
| Wed, Oct 28 FY2027 | – | $80 | 75% | – | $60 |
- GSA areas above the standard rate
- 4
- Highest lodging maximum
- $326
- Where
- Big Sky / West Yellowstone/Gardiner
- Everywhere else
- $113 + $68
Montana per diem in FY2027 peaks at $326 a night in the Big Sky / West Yellowstone / Gardiner area (Gallatin and Park counties) in June, July, August and September, and falls to $169 from October to May, with $80 of M&IE. Kalispell and Whitefish (Flathead County) reach $244, Missoula $199, and Helena is flat at $140. All other counties take the standard $113 and $68. The rates run from October 1, 2026 to September 30, 2027. The step between seasons is sharp: three nights in the Big Sky area from September 13 to 16, 2027 come to $1,258.00 at the federal maximum, while three nights from October 11 to 14, 2026 are capped at $787.00. The calculator above opens on the dearest area; type a Montana town or ZIP code to switch.
September still counts as summer in Montana
In each of the 3 seasonal Montana areas, September is billed at the peak. Big Sky / West Yellowstone / Gardiner and Missoula use the same calendar, June, July, August and September. Kalispell / Whitefish starts a month later, in July, and keeps June at its low figure of $126. October drops straight back to the off-season everywhere, with no shoulder step. That makes the turn of the fiscal year a real price cliff: a crew that worked the last week of September 2026 and the first week of October 2026 in the Big Sky area saw the lodging cap fall from $310 to $169 overnight, and the day-by-day table of the calculator shows the change on the right night.
Big Sky / West Yellowstone / Gardiner, MT: per diem for a stay
Lodging + M&IE at the federal maximum
$787
| Lodging: 3 × $169 | $507 |
| M&IE: 2 travel days at $60 | $120 |
| M&IE: 2 full days at $80 | $160 |
Lodging taxes on top; provided meals are deducted in the full calculator.
Big Sky's winter rate went down
In the Big Sky area the two seasons moved in opposite directions. The summer peak rose from $310 to $326, but the off-season maximum fell from $176 to $169. A winter assignment in Gallatin or Park County is therefore capped $7 a night lower than a year ago, while the standard rate gained $3. Kalispell rose from $232 to $244 at the top, Missoula from $195 to $199, and Helena from $132 to $140 all year. Big Sky and Kalispell sit on the $80 meal tier, Missoula and Helena on $74.
Billings, Great Falls, Butte-Silver Bow and the high-low list
Billings (Yellowstone County), Great Falls (Cascade County) and Butte-Silver Bow (Silver Bow County) have no GSA area and take $113 and $68. Employers that use the IRS high-low method should note that the Big Sky summer total, $406 a day, is above the $280 mark that puts a locality on the high-cost list for part of the year, so the $329 rate of Notice 2026-60 can apply there during the listed months. Fuel adds to the cost of long Montana drives: the EIA Rocky Mountain average was $4.417 a gallon in the week of October 5, 2026, above the national $4.354.
Fuel for a drive at Rocky Mountain (Montana) prices
Fuel cost
$47.32
| 10.7 gal × $4.417 | $47.32 |
| Per mile | $0.158 |
| Same miles at the IRS rate ($0.76) | $228 |
Every GSA area in Montana: FY2027 against FY2026
| GSA area | Counties or limits | Lodging FY2027 | M&IE | Lodging FY2026 |
|---|---|---|---|---|
| Big Sky / West Yellowstone/Gardiner | Gallatin/Park | $169 to $326 | $80 | $176 to $310 |
| Kalispell/Whitefish | Flathead | $126 to $244 | $80 | $124 to $232 |
| Missoula | Missoula | $135 to $199 | $74 | $130 to $195 |
| Helena | Lewis and Clark | $140 | $74 | $132 |
| Rest of the state | All other counties | $113 | $68 | $110 |