Route 18 is a highway in western Missouri. Its eastern terminus is at the intersection of Route 13/Route 52 and Route 7 in Clinton. Its western terminus is at the Kansas state line near Drexel. It continues into Kansas as a county road.
Route 18 begins at the Kansas state line just west of Drexel. It runs for three miles (5 km) along the Cass/Bates County line. Route 18 then turns south to Merwin, where it turns back east. It then runs through Adrian, before having a diamond interchange with the Interstate 49/U.S. Route 71 freeway.[1] Route 18 then runs south of Altona and through Ballard. It then runs through Clinton. Route 18 then ends at Routes 7, 13, and 52.