State Road 13 (SR 13) in the U.S. state of Indiana is a north–south highway in north-central and central Indiana that connects the area east of Indianapolis with the northern part of the state. Its southern terminus is in Fortville where it meets U.S. Highway 36 (US 36) and SR 67. At its northern end, signage for SR 13 ends at the interchange with the Indiana Toll Road; the highway continues unsigned for an additional 0.66 miles (1.06 km) running concurrently with US 131 to the Michigan state line. All of SR 13 is undivided surface road.