U.S. Route 20 (US 20) in Indiana is a main east–west highway that is parallel to the Indiana Toll Road. The western terminus of US 20 is at the Illinois state line and the eastern terminus is at the Ohio state line. US 20 through Whiting, East Chicago, and Gary is concurrent with US 12 twice. The route varies between one-way, two-lane, and four-lane streets, in Northwest Indiana. From the east side of Gary to west of South Bend, US 20 is a four-lane undivided highway. The route then heads around the west and south sides of South Bend and Elkhart as a four-lane limited access divided highway. East of State Road 15 (SR 15), US 20 is two-lane rural highway.

The Indiana Toll Road, officially the Indiana East–West Toll Road, is a controlled-access toll road that runs for 156.28 miles (251.51 km) east–west across northern Indiana from the Illinois state line to the Ohio state line. It has been advertised as the "Main Street of the Midwest". The entire toll road is designated as part of Interstate 90 (I-90), and the segment from Lake Station east to the Ohio state line is a concurrency with I-80. The toll road is owned by the Indiana Finance Authority and operated by the Indiana Toll Road Concession Company (ITRCC), which is owned by IFM Investors.