Heise Hot Springs surfaces at 120°F near Rexburg along East Heise Road, carrying some of the most mineral-laden water in Idaho. Chloride levels hit 2,400 mg/L and sodium reaches 1,500 mg/L, making this a genuinely saline thermal source at 5,102 feet in the upper Snake River Plain.
The spring emerges in the broad agricultural valley east of Idaho Falls, where irrigated fields stretch toward the Snake River Range foothills. Cottonwood groves line the river bottoms, and the Teton peaks stand visible to the northeast on clear days. Annual snowfall stays moderate at 47 inches, and the relatively dry climate delivers just under 18 inches of rain. The roadside setting along East Heise Road makes access straightforward.
History of Heise Hot Springs
Heise sits within the eastern Snake River Plain, where the Yellowstone hotspot track left behind fractured volcanic rock that channels deeply heated groundwater. The slightly acidic pH of 6.4 combined with extreme mineral loading, including 430 mg/L calcium and 82 mg/L magnesium, points to prolonged contact with calcium-carbonate formations at depth. This area has attracted bathers since the late 1800s, when early settlers recognized the thermal potential.
Kelly Island Campground lies about 3 miles away along the South Fork of the Snake River, offering first-come-first-served sites with a five-day stay limit. The spring is roadside with minimal walking required. The high mineral content leaves heavy deposits on rocks near the source. Bring towels you do not mind staining, and rinse gear thoroughly after soaking.
Is Heise Hot Springs worth visiting?
Best for
- Hot spring soaking
- Easy day trips
- Overnight camping trips
Heise Hot Springs offers an accessible hot spring experience — great for a day trip.
Annual Precip: 17.8 in
Annual Snow: 47.4 in
January
Air 22°F · Water 120°F · +99° contrast
December
Air 21°F · Water 120°F · +99° contrast
February
Air 26°F · Water 120°F · +95° contrast
January offers 51°F more contrast than July
Recent Temperature
138.2°F
(59.0°C)
Measured Jun 18, 1977
The water at Heise Hot Springs is slightly acidic (pH 6.4). It is notably rich in calcium (may support bone density and joint health), magnesium (known for muscle relaxation and stress relief), and sodium (supports circulation and skin hydration).
pH influences mineral absorption through skin
May support bone density and joint health
Known for muscle relaxation and stress relief
Supports circulation and skin hydration
Traditionally used for skin conditions and inflammation
Natural antiseptic with skin health benefits
Scenic, semi-developed camping in a cottonwood gallery forest along the South Fork of the Snake River with views of the Snake River Range foothills. Excellent trout fishing along with hiking, boating, wildlife viewing and OHV riding opportunities nearby. Approximate use season: Mid-May to mid/late September.
The Kelly Island Campground has no electrical hook-ups and ATV's are not allowed to be ridden in the campground. This site is equipped with a central spicket for water, vault toilets, pul...
Reserve on Recreation.gov →
Swimsuit & towel
Water bottle
Stay hydrated, especially in hot water
Warm layers
Cold air before and after soaking
Camping gear
Nearby camping at Kelly Island Campground
Trash bag
Pack out what you pack in
Water shoes
Hot ground near source
USGS Quad: HEISE 7.5 · PP 492: 152.0 · NOAA: 3.0 · AMS Map: DRIGGS
What is the water temperature at Heise Hot Springs?
Heise Hot Springs has a water temperature of 120°F (49°C). This is considered a hot spring, well above body temperature.
Where is Heise Hot Springs located?
Heise Hot Springs is located in Madison County, Idaho at 5,102 feet elevation, near Rexburg. Coordinates: 43.6440°N, 111.6870°W.
How do I get to Heise Hot Springs?
Heise Hot Springs has Roadside road access, with the nearest road being East Heise Road (222 ft from the road).
Can I camp near Heise Hot Springs?
Yes, Kelly Island Campground is located nearby (1.9 miles away).
What minerals are in the water at Heise Hot Springs?
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride. The pH is 6.4 (slightly acidic).
Is it safe to soak at Heise Hot Springs?
At 120°F, Heise Hot Springs is hot enough to require caution. Enter slowly, limit soaking sessions to 15–20 minutes, and stay hydrated. Access may be on private land or unconfirmed — verify current conditions before visiting. Always tell someone your plans before visiting remote hot springs.
Is Heise Hot Springs crowded?
Heise Hot Springs is accessible from a paved road, making it easy to reach. Weekends and holidays may be busier — consider visiting on a weekday for a quieter experience.
What should I bring to Heise Hot Springs?
Essentials for Heise Hot Springs: swimsuit, towel, water bottle, warm layers for before and after soaking, camping gear, a trash bag to pack out what you pack in. The water is over 110°F — test the temperature before entering and watch for scalding near the source.