Among the rolling, prairie hills of Southeastern Montana, Tongue River Reservoir State Park is a rare and loved place where many come to enjoy water-based activities at their best. This lake is a great place for creating memories.
Fishing, boating, swimming, and camping are the prime activities here, and the reservoir boasts excellent crappie, walleye, bass and northern pike fishing. Fly fishermen can test their skill on the river below the dam. Wildlife viewing is also plentiful, with osprey, blue herons, deer, antelope as well as a few bald eagles being regular summer sights.
The park offers 81 reservable camping sites with electric hookups, with 27 of those being double occupancy campsites (two electric hook-ups), as well as over 80 non-reservable, non-electric camping sites. Most sites have a fire ring and a picnic table. A dump station and water faucets are available during peak season, as weather permits. The park also has a fish cleaning station and over 20 vault toilets throughout the campgrounds. There are 2 boat ramps with docks for launching boats, one at Camper Point by the marina and one at Pee Wee North.
Day use areas include sheltered picnic tables at Campers Point and Sand Point. Sand Point has a small, but popular “beach area” for swimming and picnicking.
A marina store at Campers Point offers firewood, ice, fishing and boating supplies, boat rentals, boat and RV storage, bait, groceries, snacks, drinks, gasoline, souvenirs, fishing and hunting licenses and non-resident park passes.
In the winter, Tongue River Reservoir is a popular ice fishing location. Eleven campsites on Campers Point have electricity year-round. During the off season, all sites are first come, first serve.
The park is 642 acres in size at an elevation of 3,468 feet.
Hiking and historical opportunities are available nearby at Rosebud Battlefield State Park, Little Big Horn Battlefield National Monument and in Sheridan, Wyoming.
Please contact the park regarding any hunting regulations.
Park office hours during peak season are 8am to 4pm daily.
Some amenities are seasonal. Check with the park for availability.
- ADA Accessible
- Boat Launch
- Boat Rental
- Established Fire Pits
- Firewood for Sale
- Grills/Fire Rings
- Pets Allowed
- Picnic Shelter
- RV Dump Station
- RV Hookups
- Toilets (Vault)
- Trash Removal
Hours listed below are normal operating hours and may not apply when there is a special restriction or closure. Check Alerts and Closures in the tab below.
Open daily all year
Open year round
Electricity available at some campgrounds
Group areas & playground are open
Water & Fish Cleaning Stations
Available approximately early-May through Sept. 30th depending on weather
Restrictions and Closures
See a current list of Restrictions and Closures on State Parks and other FWP lands that may be affected by floods, fire, drought or major maintenance activities.
Contact the park manager for open volunteer positions at Tongue River Reservoir State Park.
For complete position descriptions, application forms, and details about Montana State Parks volunteer programs, visit the Volunteers page.
- Montana residents who pay the $9 state parks fee with their annual vehicle registration have no daily entrance fees to state parks. For residents who don't include this in their vehicle registration, non-resident day use fees apply.
- Day use entrance fee with a vehicle: $8
- Day use entrance fee as a walk-in, bicycle or bus passenger: $4
- With a Nonresident Entrance Pass: Free
- Campsite fees range from $4-$34 per night, depending on season and available amenities.
Montana State Parks offers hike/bike, rustic, tent, rv, and boatslip campsites.
Visit Reserve America to check fees and reserve a campsite for Tounge River Reservoir State Park.
Tongue River Reservoir State Park
PO Box 8
Decker, MT 59025
Reservation Phone Number: