SR 278 was established in 1991 to serve the Coeur d'Alene Reservation in Idaho and used the route of an old gravel road that dates back to the 1930s.

The highway enters the town parallel to a Union Pacific rail line and crosses over Rock Creek to an intersection with 1st Street.

[3] SR 278 turns south onto 1st Street and leaves Rockford, crossing over Rock Creek and beginning to parallel it east as Hoxie Road to the Idaho state line, where the roadway becomes Idaho State Highway 58, continuing 2.943 miles (4.736 km) to U.S. Route 95 (US-95).

[6] The route of SR 278 was previously Hoxie Road, which was graveled in 1938 and later paved by the 1950s.

[7][8] Hoxie Road was signed as SR 278 in 1991,[2] and no further major revisions have occurred.