Montana State Parks · Montana
Big Arm State Park
Montana State Parks · Montana, United States
- Sites
- 41
- Max RV length
- 40 ft
- Group sites
- Yes
- Drinking water
- Yes
- Restrooms
- Yes
- Showers
- Yes
- Pets
- Yes
- Elevation
- 2,979 ft
- Dark sky
- Bortle class 1
- Cell coverage
- T-Mobile good · AT&T good · Verizon good (carriers' 4G LTE filings to the FCC, 2025-12; not measured here)
- Address
- 28031 Big Arm State Park Rd., Big Arm, MT 59910
- Phone
- 406-849-5256
About
Big Arm State Park, one of Flathead Lake State Park's five mainland units, is a Montana FWP state park with 41 campsites including a group site and three yurts.
Fees
Montana FWP's statewide camping rate: $4-$34 per night, depending on season and available amenities. Plus Montana's day-use entrance fee (in addition to the nightly camping rate): Montana residents who pay the $9 state parks fee with vehicle registration owe no daily entrance fee; nonresidents pay $8/vehicle or $4/walk-in per day (or $50/year for a Nonresident Entrance Pass, $35 for a 7-day pass). A 50% camping-fee discount applies statewide to Montana-resident seniors (62+), veterans and people with disabilities.
Weather, month by month
| Month | Typical high | Typical low | Coldest night | Hottest day | Years with a night below 32°F |
|---|---|---|---|---|---|
| January | 35° | 25° | -14° | 42° | 11 of 11 |
| February | 34° | 22° | -8° | 49° | 11 of 11 |
| March | 43° | 30° | 6° | 60° | 11 of 11 |
| April | 49° | 34° | 15° | 73° | 6 of 11 |
| May | 62° | 42° | 35° | 83° | 0 of 11 |
| June | 71° | 51° | 39° | 87° | 0 of 11 |
| July | 85° | 62° | 50° | 97° | 0 of 11 |
| August | 84° | 63° | 49° | 99° | 0 of 11 |
| September | 72° | 54° | 43° | 87° | 0 of 11 |
| October | 57° | 40° | 32° | 75° | 0 of 10 |
| November | 43° | 33° | 17° | 59° | 6 of 10 |
| December | 36° | 31° | 8° | 49° | 9 of 10 |
Mid-month figures from 2016–2026 of daily weather at this spot (ERA5 reanalysis via Open-Meteo, CC BY 4.0), in °F. Typical is the median; coldest and hottest are the extremes seen.
Nearby campgrounds
- Lake Mary Ronan State Park · Montana State Parks · 9 mi · 25 sites
- Finley Point State Park · Montana State Parks · 11 mi · 29 sites
- West Shore State Park · Montana State Parks · 12 mi · 33 sites
- Blue Bay Campground · Tribal Lands · 13 mi · 22 sites
- Yellow Bay State Park · Montana State Parks · 14 mi · 5 sites
All public campgrounds in Montana · Every state and province · Facts read from the operator 2026-08-25. Confirm fees, rules and current status with the operator before you go.