State Route 257 is a highway in central Utah that runs from the junction of SR-21 in Milford to US-6/US-50 sixty-nine miles (111 kilometers) to the north in Hinckley.

From its southern terminus in Beaver County, SR-257 generally north until Black Rock, where it makes a turn to the northwest.

It stays north-northwest until the northern terminus of the route, located in Millard County.

Most of the route is paralleled by Lynndyl Subdivision of the Union Pacific Railroad.

[3] A short loop through downtown Hinckley, heading west from SR-140 on 2500 South and north on Main Street to SR-27, was added as State Route 240 in 1966 but dropped from the state highway system in 1969.