# Bonneville Hot Springs, Idaho

Bonneville Hot Springs in Idaho. 185°F (85°C). Short Walk · Public Land. Boise County.

- Page: https://www.soakingsprings.com/hot-springs/idaho/bonneville-hot-springs
- Source: Soaking Springs, researched and maintained by Armen Suny
- Updated: 2026-09-14

## Can you soak at Bonneville Hot Springs?

Yes. Bonneville Hot Springs has natural, undeveloped pools that run at 104°F. You pay $5 for parking or a permit as of October 2026. It's open Apr–Oct. It's a short walk from the road.

## Key facts

| Fact | Value |
|---|---|
| Source water temperature | 185°F (85°C) (USGS record; developed pools are often cooled) |
| pH | 9.3 (Alkaline) |
| Elevation | 4,880 ft |
| Access | Short Walk · Public Land, 0.3 mi from the nearest road (Bonneville Trailhead Road) |
| Land | Boise National Forest, US Forest Service |
| County | Boise County |
| Nearest town | Idaho City |
| Coordinates | 44.15700, -115.31400 |
| Best months to soak | December, January, February (largest gap between water and average air temperature) |
| Nearest campground | BONNEVILLE, 0.4 mi |

## Plan your visit

| | |
|---|---|
| Type | Primitive pools |
| Cost | $5 parking or permit. $5 per vehicle day use at Bonneville Campground (recreation.gov: non-camper day use); America the Beautiful pass accepted per one guide |
| Season | Apr–Oct |
| Reservations | Not needed |
| Pool temperature | 104°F |
| Clothing | Swimsuit required |
| Getting there | 0.25 to 0.4 mi easy trail from Bonneville Campground along Warm Springs Creek |
| In winter | Gate closed off-season, adds about 1 mi walk; snowshoes or skis when snowy |
| Operator | US Forest Service, Boise National Forest (Lowman Ranger District), https://www.recreation.gov/camping/campgrounds/232311 |

Checked October 2026. Sources: https://www.recreation.gov/camping/campgrounds/232311, https://idahohotsprings.com/destinations/bonneville, https://www.hotspringsguides.com/hot-springs/bonneville-hot-springs-idaho

## Soaking safety

**Very Hot Source, Use Extreme Caution.** At 185°F, the source water at Bonneville Hot Springs is hot enough to cause burns. Some hot springs this hot have cooler side pools or downstream areas suitable for soaking. Always test the water temperature before entering.

## About Bonneville Hot Springs

Nobody is putting a hand in this water. Bonneville Hot Springs runs scalding where it surfaces, in the Boise National Forest of Boise County, and the nearest town, Idaho City, sits a long 34 miles off. Access is listed as open. A Forest Service campground of the same name sits close by, so of the places in the forest north of Idaho City, this is one of the easier ones to sleep beside.

You leave the car at the end of Bonneville Trailhead Road and walk about a third of a mile. The spring sits at mid elevation in conifer country and the winters here are heavy. Something close to fifteen feet of snow lands in an average year. The rest of the year brings a fair amount of rain, so this is wet mountain forest, nothing like the sagebrush country further south in the state.

December through February carry the best-months tag on file, which is odd given how much snow falls, so treat that as a note about the water and find out whether the trailhead road is even passable before you drive up. Bonneville campground is under half a mile away. The temperature reading dates from a survey in 1979. Source water that hot will burn you. Nothing on file says whether there is a cooler pool downstream.

## Water chemistry

Lab sample from 1979-03-13 (Water Quality Portal).

| Measure | Value |
|---|---|
| pH | 9.3 |
| Calcium | 1.5 mg/L |
| Magnesium | 0.1 mg/L |
| Sodium | 77 mg/L |
| Sulfate | 50 mg/L |
| Chloride | 8 mg/L |

## Nearby

- Nearest city page: [Hot springs near Challis](https://www.soakingsprings.com/hot-springs/near/idaho/challis), 26 mi away
- State page: [Hot springs in Idaho](https://www.soakingsprings.com/hot-springs/idaho)
- [Sacajawea Hot Springs, ID](https://www.soakingsprings.com/hot-springs/idaho/sacajawea-hot-springs): 153°F source, Roadside, near Idaho City, Boise County, primitive pools, free, jul–oct
- [Grandjean Hot Spring, ID](https://www.soakingsprings.com/hot-springs/idaho/grandjean-hot-spring): Hot, Roadside, near Idaho City, Boise County
- [Kirkham Hot Springs, ID](https://www.soakingsprings.com/hot-springs/idaho/kirkham-hot-springs): 149°F source, pH 9.1, Short Walk, near Idaho City, Boise County, primitive pools, $5 parking or permit, may–sep
- [Haven Lodge Hot Spring, ID](https://www.soakingsprings.com/hot-springs/idaho/haven-lodge-hot-spring): 147°F source, pH 9.2, Short Walk, near Idaho City, Boise County, developed pools, pools 85–104°F, $20 day pass, year-round
- [Cape Horn Warm Springs, ID](https://www.soakingsprings.com/hot-springs/idaho/cape-horn-warm-springs): 95°F source, pH 9.6, Short Walk, near Idaho City, Boise County
- [Pine Flat Hot Springs, ID](https://www.soakingsprings.com/hot-springs/idaho/pine-flat-hot-springs): 138°F source, pH 9.2, Short Walk, near Idaho City, Boise County, primitive pools

## Questions

**What is the water temperature at Bonneville Hot Springs?**
Bonneville Hot Springs has a water temperature of 185°F (85°C). This is considered a hot spring, well above body temperature.

**Where is Bonneville Hot Springs located?**
Bonneville Hot Springs is located in Boise County, Idaho at 4,880 feet elevation, near Idaho City. Coordinates: 44.1570°N, 115.3140°W.

**How do I get to Bonneville Hot Springs?**
Bonneville Hot Springs has Short Walk road access, with the nearest road being Bonneville Trailhead Road (0.3 mi from the road).

**Is Bonneville Hot Springs free to visit?**
Bonneville Hot Springs has Open access. It is managed by US Forest Service.

**Can I camp near Bonneville Hot Springs?**
Yes, Bonneville is located nearby (0.4 miles away).

**What minerals are in the water at Bonneville Hot Springs?**
Water chemistry analysis shows the presence of pH, Calcium, Magnesium, Sodium, Sulfate, Chloride. The pH is 9.3 (alkaline).

**Is it safe to soak at Bonneville Hot Springs?**
No, not at the source. The water at Bonneville Hot Springs reaches 185°F, which can cause severe burns within seconds. Look for cooled side pools or downstream stretches, and test with a hand before anything else.

## Sources

- USGS thermal springs records, Water Quality Portal lab analyses, OpenStreetMap, Wikipedia/Wikidata, NOAA climate normals