U.S. Route 20 (US 20) is a United States Numbered Highway that runs from Newport, Oregon, to Boston, Massachusetts.

The route parallels the Ohio Turnpike (Interstate 80 [I-80]/I-90) through rural farmland in the northwest corner of the state.

From Fremont eastward, the route becomes a divided highway, except when passing through the communities of Clyde, Bellevue, and Monroeville.

From there, the route passes through Public Square easterly, paralleling US 322 one block to the south until nearing Case Western Reserve University.

It travels northeasterly through the east side of Cleveland as Euclid Avenue, then through the suburbs of Euclid, Wickliffe, Willoughby, Mentor, Ohio, and Painesville, then continues easterly, roughly paralleling the Lake Erie shoreline through Geneva, Ashtabula, and Conneaut and into Pennsylvania.