U.S. Federal Route 31 is a north-south highway through the center of St. Joseph County. Around a portion of the South Bend Area, this highway is a expressway. Some areas call it "BY-PASS" U.S. Rt. 31. Portions of the old alignmet is known as BUSN. U.S. Rt. 31. U.S. Rt. 31 passes through the following towns in St. Joseph County. South Bend
Lakeville
U.S. Rt. 31 is multi-plexed in St. Joseph County. U.S. Rt. 20, in South Bend.
Branches of U.S. Rt. 31 in St. Joseph County. NB U.S. Rt. 31 north of the Marshall/St. Joesph County Line. NB U.S. Rt. 31 in Lakeville. NB U.S. Rt. 31 south of South Bend. A set of BGS's on NB U.S. Rt. 31. Another BGS on NB U.S. Rt. 31. NOTE: U.S. Rt. 20 is labeled at "BY-PASS". A BGS on WB U.S. Rt. 20/NB U.S. Rt. 31. WB U.S. Rt. 20/NB U.S. Rt. 31 west of U.S. Rt. 31/BUSN U.S. Rt. 31. WB U.S. Rt. 20/NB U.S. Rt. 31 on the southwest side of South Bend. A marker on WB U.S. Rt. 20/NB U.S. Rt. 31 on the westside of South Bend. WB U.S. Rt. 20/NB U.S. Rt. 31 south of IN St Rt 23. A BGS on WB IN St Rt 2. WB U.S. Rt. 20/NB U.S. Rt. 31 north of IN St Rt 2. A BGS near the South Bend Airport. NB U.S. Rt. 31 south of I-80/90/IN E-W Toll Road. A BGS on WB I-80/90/IN E-W Toll Road. BGS on WB I-80/90.