Boulder Hot Springs Inn & Spa
By the HotSpringsFind editorial team · How we compile records · Reviewed September 2026
Boulder Hot Springs Inn & Spa is a resort hot spring listed near Boulder, Montana. Reported soak temperature: 100°F. See the visit fact sheet.
Current status
Historic 1890s mission-style inn 3 mi south of Boulder MT on Hwy 69 — OPEN and operating year-round; day use daily 10am-8pm, $12 adults/$10 seniors/$7 kids weekdays, $14/$12/$8 weekends & holidays; outdoor geothermal pool 96-100F plus indoor 103-106F plunges (women's + co-ed) and natural mineral steam rooms.
Checked September 2026 · verified on the operator’s site · 6 sources ↓
Staying overnight?
A Boulder Valley town stay; the hot-springs inn is a separate property south of town.
Boulder is about 3 mi from the spring (straight line).
We may earn a commission from bookings through these links, at no extra cost to you.
Before you go
- Status: Open — last verified below — confirm via Visit Montana listing — Boulder Hot Springs (pool temps, directions).
- Cost: Reported $12 — confirm current rates before visiting.
- Getting there: Developed resort — confirm operating hours and any reservation requirement.
- Water: Reported soak temperature 100°F — always test the water before entering.
- Rules: Reported clothing required; pets reported not allowed — confirm current rules.
- Conditions: check weather, fire closures, and land-manager alerts the week you go — mountain access changes seasonally.
- Reservations/permits: None — day-use fee at front desk; lodging via eviivo booking link or 406-225-4339.
- Best time to go: Weekdays; winter evenings in the outdoor pool during snowfall are the signature experience.
- Clothing reality: Official: swimsuit required in co-ed pool; women's plunge side historically clothing-optional per long-standing custom (not stated on current site — call ahead). Customary: suits in outdoor/co-ed; some nude use in gendered plunge. Legal: venue rules govern.
- Kids: Allowed.
- Cell service: spotty — download maps and tell someone your plan.
- Accessibility: Pool handicap-accessible 'with assistance' per operator; 2025 grant application earmarked ADA upgrades — historic building limits remain.
- Showers REQUIRED before entering all pool/spa facilities
- No lifeguard — children under 12 must be accompanied by an adult
- Alcohol-free, drug-free, smoke-free property (healing-retreat ethos)
- Outdoor pool uses bromine (no chlorine); indoor plunges are continuous-flow, cleaned nightly
- Massage requires advance reservation at front desk
- Building is a 130-year-old restoration-in-progress — expect ongoing renovation work
- 10-visit pass sold for price of 9
- Hazard: Indoor plunge water 103-106F — limit soak time
- Hazard: Women's side cool plunge under 70F — cold-shock contrast
About this spring
National Register-listed 1910 mission-style inn in Peace Valley at the foot of the Elkhorn Mountains — indoor plunge 104-106°F year-round, 20x60 ft outdoor pool 92-100°F seasonally, plus steam rooms; an alcohol/drug/smoke-free wellness retreat. Fee: $12-14 adult day use. No alcohol/smoking on property; showers mandatory pre-soak.
Boulder Hot Springs stands in a valley where, tradition holds, Native peoples agreed to lay down their weapons and share the waters — the origin of the name Peace Valley. Prospector James Riley filed land and water rights on the springs in the 1860s and built a crude bathhouse and tavern; after his 1882 death from smallpox, later owners completed a hotel that was remodeled and enlarged in Queen Anne style in 1891 with fifty-two rooms, electricity and a resident physician. Between 1910 and 1913, under Butte millionaire James A. Murray, the bathhouse and wings were added and the Victorian structure was wrapped in stucco and raised parapets, producing the California Mission-style landmark seen today, complete with Tiffany amber-glass lobby lighting. The hotel later passed to Murray's nephew, future U.S. Senator James E. Murray, spent roughly 35 years as the Diamond S Ranchotel dude ranch, and was placed on the National Register by owner Stuart Lewin before closing in 1989; restored under new ownership, it reopened in 1991. Now an alcohol- and smoke-free wellness retreat, it runs a year-round indoor plunge and a seasonal outdoor pool.
Directions & trailhead access
31 Hot Springs Rd, Boulder — I-15 Boulder exit, 3 mi south on Hwy 69.
Montana geothermal context
Montana's springs cluster around Yellowstone's northern margin and along basin-range faults in the western half of the state. A large share of named sites sit on private ranch land or have limited legal access, which is why status notes matter here. Cold winters and heavy spring runoff reshuffle riverside pools every year.
What a resort site means here
A resort spring is a commercial operation: developed pools or tubs with controlled temperatures, changing facilities, and usually day-use fees or lodging packages. Expect posted rules (swimsuits, quiet hours, age limits), staff on site, and in many cases required reservations — especially on weekends and holidays.
Best time to visit
Year-Round (Best: May – October)Pool temperatures and access can change with weather and season. Outdoor ambient temperatures fluctuate significantly across Montana. Late spring through autumn offers the most comfortable road access.
Fact sheet
| Reported soak temp | 100°F |
|---|---|
| Source temp (historical) | 100°F |
| Trail access | Recorded coordinates — access unverified |
| Access fee | Reported $12 — verify |
| Clothing policy | Reported clothing required |
| Pet policy | Reported no pets |
| Geothermal data reference | NOAA Thermal Springs List (1980 archive) |
| Check land status | Visit Montana listing — Boulder Hot Springs (pool temps, directions) |
Boulder Hot Springs Inn & Spa FAQ
Is Boulder Hot Springs Inn & Spa open right now?
Historic 1890s mission-style inn 3 mi south of Boulder MT on Hwy 69 — OPEN and operating year-round; day use daily 10am-8pm, $12 adults/$10 seniors/$7 kids weekdays, $14/$12/$8 weekends & holidays; outdoor geothermal pool 96-100F plus indoor 103-106F plunges (women's + co-ed) and natural mineral steam rooms. (Status verified on the operator’s site, last checked September 2026.)
Is Boulder Hot Springs Inn & Spa free?
Boulder Hot Springs Inn & Spa is listed with reported fees near Boulder. Fees are reported; confirm admission, parking and permit costs with the site manager.
What temperature is Boulder Hot Springs Inn & Spa?
Boulder Hot Springs Inn & Spa has a reported soak temperature of 100°F and a historical source temperature of 100°F in survey records. Historical data may not reflect current conditions — always test water before entering.
Is Boulder Hot Springs Inn & Spa clothing optional?
Boulder Hot Springs Inn & Spa is listed as swimsuit-required in directory records. Confirm current rules before visiting, as policies change.
How do you access Boulder Hot Springs Inn & Spa?
Boulder Hot Springs Inn & Spa is a private venue with paid public admission. Confirm current hours, fees and booking requirements with the operator before visiting.
Where to stay in Boulder
A Boulder Valley town stay; the hot-springs inn is a separate property south of town.
Boulder is about 3 mi from the spring (straight line).
We may earn a commission from bookings through these links, at no extra cost to you.
Sources & references
- Boulder Hot Springs — official Spa & Springs page (rates, pool temps, rules, hours 10am-8pm daily) — operator · 2026
- Boulder Hot Springs — official home (day-use hours, alcohol/smoke-free mission) — operator · 2026
- KTVH — 'Boulder Hot Springs honors history with new round of renovations' (open year-round, $500K preservation grant, ownership since 1989) — news · 2025
- Boulder Monitor — 'County, Hot Springs vie for preservation grants' (Jan 2025 grant ask for co-ed pool foundation cracks, ADA work) — news · 2025-01
- Visit Montana listing — Boulder Hot Springs (pool temps, directions) — official · 2025
Additional references for this record; a source link does not guarantee current conditions.
Details above were verified against the named sources on their listed dates — conditions change, so recheck before traveling. · How we verify our data · Report a correction
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