Boulder Hot Springs | Southwest Montana

Boulder Hot Springs is a scenic resort in the heart of the picturesque Peace Valley among the meadows, wetlands, and forests 33 miles south of Helena.

The resort has a rich history and heritage. Its story traces back to the 19th century when a saloon and bathhouse were built for local miners and ranchers.

Over the years, it became a hot spot for celebrities and even presidents. Teddy Roosevelt lodged here during his presidency while on a hunting trip, and Franklin D. Roosevelt stopped at the resort during his Butte visit.

Today, Boulder Hot Springs is still a fantastic spot to escape from everyday routine, relax at the hot springs, and enjoy the great outdoors. You can swing by the resort and get a day pass to soak at the hot spring pools or stay overnight at one of the hotel rooms.

Geothermal Water & Soaking

The geothermal mineral water comes out of the 32 springs at temperatures ranging from 125° F to 180° F (52° C - 82° C). Then, it is mixed with cool spring water and channeled into 1 outdoor and 3 indoor pools.

The indoor bathhouse has women's only and mixed-gender areas.

Outdoor pool temperature ranges from 96° F to 100° F (36° C - 38° C). The pool water is treated with bromine, a less harsh agent than chlorine. This pool is also accessible to people with disabilities.

The mixed-gender and women's hot pools are kept within 103° F to 106° F (39° C - 41° C). Both pools are flow-through, and the water completely refreshes every 4 hours, so no chemicals are used.

The women's cool pool temperature is usually 70° F (21° C). Workers clean and drain it regularly, so no chemicals are needed.

There is no cool pool on the mixed-gender side of the bathhouse. The bathhouse's mixed-gender and women's sections have dressing rooms and steam rooms. The heated sidewalk connects the bathhouse and the outdoor pool.

Children under the age of 12 must be with an adult at all times.

This is a developed location, so swimsuits are mandatory throughout the resort.

You can also book a massage at the resort's spa.

Location: 33 miles south of Helena • Southwestern Montana • USA
Open: Year-round
Development: Outdoor pool, indoor pools, steam room, spa
Clothing: Mandatory
Amenities & Services: Hotel with breakfast, meeting rooms

Hiking distance: Short
Road access: Any vehicle
Day-use fees: Yes

Elevation: 5,000 ft (1,524 m)

Water T° (source): 125° F - 180° F (52° C - 82° C)
Water T° (outdoor pool): 96° F - 100° F (36° C - 38° C)
Water T° (hot pools): 103° F - 106° F (39° C - 41° C)
Water T° (soaking pool): 70° F (21° C)
Odor: None
Chemical used: Bromine at the outdoor pool. None at other pools

Minerals:
Sodium (106 mg/L)
Bicarbonate (123 mg/L)
Chloride (18 mg/L)
Potassium (4.9 mg/L)
Calcium (2.4 mg/L)
Lithium (0.20 mg/L)
Magnesium (0.1mg/L)
Silica (49.7 mg/L)
Sulfate (73.9 mg/L)