Missoula to Richfield: Epic Montana-Utah Road Trip Guide

The drive from Missoula, MT to Richfield, UT covers roughly 660 miles along I-15 and I-90, winding through three states and a remarkable diversity of landscapes. A little-known fact: this route closely follows the path of the 1800s Mormon Trail through the Snake River Plain, and near Dillon, MT, you'll cross the Continental Divide at Monida Pass (elevation 6,870 ft), a historic crossing used by pioneers. The journey typically takes 9 to 10 hours of pure driving, but plan for at least two days to fully absorb the sights.

This guide provides an exhaustive breakdown of everything you need to know, from natural landscapes to fuel economics, culinary stops, family suitability, and hidden off-route spots. Whether you're wondering how long to drive Missoula to Richfield or if it's worth driving, the answer is yes—but only if you know where to stop.

Before we dive in, check out this resource on how to find the best stops and hidden gems between cities to enhance your trip planning.

The landscapes evolve dramatically. From Missoula, you traverse the pine-clad Rocky Mountains, crossing the Continental Divide near Butte. The Deerlodge National Forest offers sweeping views of the Pintler Range. As you descend into Idaho, the terrain opens into the Snake River Plain, a vast volcanic plateau dotted with buttes and lava fields. Near the Idaho/Utah border, the Wasatch Range rises to the east, and the Sevier Plateau frames Richfield.

UNESCO World Heritage Sites include Yellowstone National Park (a detour from Idaho Falls, about 90 miles east) and the recently inscribed Moravian Church Settlements in Utah? Actually, Utah has no UNESCO sites on this route, but Yellowstone is a major attraction worth the side trip. Also consider the Bear River Migratory Bird Refuge near Brigham City, UT.

Local commerce varies by region. In Montana, you'll find fly-fishing shops and artisanal goods; in Idaho, potato farms and Basque culture (Boise is a detour); in Utah, dairy farms and pioneer heritage. Don't miss the weekly farmers' markets in Butte (Tuesdays) and Idaho Falls (Saturdays).

Hidden off-route spots: Take the exit for Arco, ID (exit 23 on I-15) to see the world's first nuclear power plant (Experimental Breeder Reactor I, now a museum). Another gem: the town of Lava Hot Springs, ID, just off I-15, offers natural hot springs and a historic pool complex—perfect for soaking tired muscles.

The interstates are well-engineered, but hazards include wildlife (deer, elk, and antelope) especially at dawn/dusk, sudden snowstorms even in spring/fall, and long stretches without services in central Idaho. Always carry an emergency kit with water, blankets, and a flashlight. The road quality is rated good to excellent, with occasional frost heaves in Montana.

For families: stop at the Montana Science Center in Bozeman (detour), the Idaho Museum of Natural History in Pocatello, or the Cove Fort historic site in Utah. Richfield has the Fremont Indian State Park with petroglyphs and hiking. Child-friendly rest areas are plentiful, with clean facilities and picnic tables.

The route is straightforward: start on I-90 East from Missoula, then connect to I-15 South near Butte, MT. From there, stay on I-15 through Idaho and into Utah until you reach exit 40 for Richfield. Road quality is generally excellent, with well-maintained interstates and clear signage.

Fuel stations are plentiful along the interstate, but gaps exist in remote stretches—particularly between Dillon, MT and Idaho Falls, ID (about 120 miles). Plan to fill up in Butte, MT (mile 120) and again in Idaho Falls, ID (mile 350).

For EV drivers, charging stations are available in Missoula, Butte, Idaho Falls, and Richfield, but slower Level 2 chargers may be found in smaller towns. It's wise to top off whenever you stop, as winter temperatures can reduce range.