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Flathead Lake Camping & RV Parks (2026): Best Campgrounds by ShoreCompare Flathead Lake campgrounds by hookups, showers, RV limits, location, and current Montana State Parks fees before you reserve.
State park · Flathead Lake · Montana
Big Arm State Park is a Montana Fish, Wildlife & Parks campground on the southwest shore of Flathead Lake, 15 miles north of Polson. FWP lists 41 campsites, one group site and three yurts, with food-storage lockers and a seasonal shower house and flush toilets that normally run mid-May through mid-September. Its real advantage is location: Big Arm is a common launch point for Wild Horse Island, which is reachable only by boat. It suits self-contained campers who want the lake and the island more than utilities.
| Hookups | None listed |
|---|---|
| Max RV length | 40 ft |
| Cost | $4–$34 |
| Fees | Rate varies by site, season, residency and pass treatment. |
| Reservations | Montana FWP reservation |
Source-backed: Montana FWP (checked 2026-07-18). Rates and site details change — verify with the operator before you book. Compare it with every other park we track in the price index.
Big Arm State Park is a Montana Fish, Wildlife & Parks campground on the southwest shore of Flathead Lake, 15 miles north of Polson. FWP lists 41 campsites, one group site and three yurts, with food-storage lockers and a seasonal shower house and flush toilets that normally run mid-May through mid-September. Its real advantage is location: Big Arm is a common launch point for Wild Horse Island, which is reachable only by boat. It suits self-contained campers who want the lake and the island more than utilities.
There are no hookups. Big Arm is not on FWP's electricity list, so plan to camp dry unless the exact reservation listing says otherwise, and note that no state park unit on Flathead Lake has sewer at the site. The published maximum RV or trailer length is 40 feet, but individual driveways can be shorter, so read the site record. Fees run $4 to $34 per night depending on site, season, residency and pass treatment, booked through Montana FWP on a rolling three-month window. July and August are warmest and busiest. The trade-off is no power and no consistently published water fill or dump station, so identify a service stop in Polson or Kalispell first.
Excerpts from the RV Parks Guide articles that cover this campground. Each links to the full guide.
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Flathead Lake Camping & RV Parks (2026): Best Campgrounds by ShoreCompare Flathead Lake campgrounds by hookups, showers, RV limits, location, and current Montana State Parks fees before you reserve.
Our verdict
Book Big Arm if you are self-contained and want Flathead Lake shoreline with easy Wild Horse Island access. Skip it if you need electric, water or sewer at the site; Finley Point or West Shore have electric, and private parks have full hookups.
No. Big Arm is not on FWP's list of Flathead Lake units with electric sites, and no state park on the lake has sewer at the site. Plan to camp without hookups.
Montana FWP lists $4-$34 per night, with the exact amount depending on season, site type, residency and pass treatment shown at checkout.
FWP publishes a 40-foot RV/trailer maximum. Individual driveways can be shorter, so check the reservation record before paying.
Reserve through Montana FWP, which uses a rolling three-month window. July weekends still need advance planning.
About 15 miles north of Polson on the southwest side of Flathead Lake.
Our guide notes the shower house and flush toilets normally operate mid-May through mid-September; check the unit's current operating status for camping dates outside summer.
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