At East Cottonwood Road it is joined by SR 53, and all four routes run straight north, only to make a slight north-northwest turn at Washington Avenue.

US 431 Bus./SR 1 branches off to the northeast onto Reeves Street to rejoin US 431, while US 231 Bus./SR 53 curves to the northwest onto Montgomery Highway.

It runs along Lake Parkway and Colloredo Boulevard, along the west side of downtown Shelbyville.

U.S. Route 231 Business in Shelbyville, Tennessee bypasses the downtown square by running from SR 387 to North Main Street, then turns left to end at the intersection of US 231, Colloredo Boulevard, and Fairfield Pike.

is a business route of and an original alignment of US 231 in Bowling Green, Kentucky.

It runs through the inner part of the city and bypasses the campus of Western Kentucky University.

Major intersections The entire route is in Bowling Green, Warren County.