Quick FactsOverview
About Bonneville Hot Springs, Idaho
Bonneville Hot Springs, Idaho is a paid natural geothermal site in the Boise National Forest along Warm Springs Creek, accessible via a short 0.4-mile trail from the Bonneville Campground trailhead off Highway 21, roughly 20 miles northeast of Lowman. The springs consist of volunteer-built rock-walled pools along the creek at varying temperatures, plus a rustic wooden soak shack on a small bluff containing a cast iron bathtub fed directly from the geothermal source. It is one of the most secluded natural hot springs near Lowman in central Idaho, set in a forested canyon rather than alongside a highway.
The site is managed by the U.S. Forest Service under the Lowman Ranger District. A day-use fee applies at the parking area during the campground's open season, and America the Beautiful passes are accepted. Outside the seasonal window, typically mid-April through October, the campground gate is closed and the walk to the springs extends by roughly a mile.
Hot water emerges from the hillside and cascades toward the creek in small waterfalls before pooling in the rock-walled soaking areas. Visitors exploring natural hot springs in Idaho who value seclusion and forest setting over roadside convenience will find Bonneville well suited to that preference.
Location & Access
Getting to Bonneville Hot Springs
Bonneville Hot Springs is reached by driving to the campground turnoff at milepost 91.5 on Idaho Highway 21, then following the gravel road approximately 0.2 miles to the day-use parking area, from which a 0.4-mile trail leads to the springs along Warm Springs Creek. From Stanley, head west on Highway 21 for approximately 39 to 40 miles, a drive of around 45 minutes. From Boise, the drive is approximately 94 miles northeast on Highway 21 via Banks and Lowman, taking around two hours.
The campground entrance and hot spring trailhead are both signed from the highway. Cell service is essentially absent in the area, so downloading an offline map before departure is important. For visitors looking for hot springs near Lowman with a short trail and forest setting, Bonneville is the most secluded option along the Highway 21 corridor.
Day-use parking requires a $5 per-vehicle fee payable at the self-service station, or a valid America the Beautiful pass displayed on the dashboard. The trail to the springs is easy and suitable for most fitness levels, though it can be muddy and slick after rain or during snowmelt. The campground has 22 sites reservable through recreation.gov during the open season, making an overnight stay a practical option for those who want early morning access before day-use crowds arrive.
Suitability & Accessibility
Who Should Visit Bonneville Hot Springs
Bonneville Hot Springs suits hikers, campers, and travelers seeking a more secluded natural hot springs experience in a forest setting, as the short trail keeps visitor numbers somewhat lower than fully roadside springs and the campground provides a convenient overnight base. The combination of rock-walled creek pools and the private soak shack with the cast iron bathtub gives visitors two distinct soaking options at the same site, suiting both those who want a social poolside experience and those who prefer a private enclosed soak. For those exploring natural hot springs in Idaho along the Ponderosa Pine Scenic Byway, Bonneville is one of the most rewarding stops on the corridor.
The 0.4-mile trail is easy and suitable for most adults and older children, though it is unpaved and can be muddy in wet conditions. Late summer and early fall tend to offer the best balance of water temperatures, drier trail conditions, and manageable visitor numbers.
Nudity is prohibited under Lowman Ranger District rules, and swimwear is required at all times. Pets and glass containers are not permitted at the springs. Those seeking a fully developed resort experience with changing rooms or consistent pool temperatures will find Bonneville does not offer those amenities, as it is an undeveloped natural site maintained informally by volunteers and managed minimally by the Forest Service.
Safety & Etiquette
Safety and Etiquette at Bonneville Hot Springs
Bonneville Hot Springs is a be-mindful site where water temperature varies significantly between pools and visitors should test every pool before entering, as the geothermal source emerges at temperatures well above safe soaking range and mixing with creek water creates variable conditions at different points. Some areas of the geothermal field are scalding and not safe to enter at all. Walking carefully and staying on established paths when moving between pools is essential, as ground near active geothermal seeps can be unstable and hot underfoot.
The soak shack contains a cast iron bathtub fed from the spring. Instructions on site ask visitors to drain the tub after each use by pulling the wooden stopper. Allowing the previous party to finish and drain before entering the shack is both courteous and a practical safety step. Water in the tub can reach 104 degrees Fahrenheit; anyone with heat sensitivity, cardiovascular conditions, or who is pregnant should limit soak time and approach with caution.
The Lowman Ranger District prohibits nudity and soap use at the springs. Pets are not allowed at or near the springs, and glass containers are prohibited. Leave No Trace principles apply: pack out all waste, do not remove rocks from pool walls, and avoid trampling vegetation near the creek. Bear activity is possible in this part of Boise National Forest, so storing food securely is a standard precaution. The trail and parking area have no lighting; plan to leave before dark. In winter and early spring the access road and trail can be icy; checking conditions before the drive from Lowman or Stanley is recommended.
