It proceeds northwesterly, passing through rural area of the Idaho National Laboratory, before bending and traveling northward.

The route continues eastward into Rexburg as Main Street before turning northward on 2nd East.

The route bends back eastward, restarting its mileage at exactly 100 miles, and proceeds to the community of Teton.

The road proceeds southward through Driggs, intersecting SH-31 in the community of Victor, and bending southeast.

As the Teton Pass Highway, it continues to its eastern termination at the Wyoming state line, at an approximate elevation of 6,690 feet (2,040 m) above sea level.