SR 23 continues north until Walkerton in the extreme southwestern corner of St. Joseph County, where it meets US 6.

As it enters the South Bend metropolitan area, SR 23 has an interchange with US 20/US 31 (the St. Joseph Valley Parkway).

It then traverses the city of South Bend from southwest to northeast, passing very near the campus of the University of Notre Dame.

From there SR 23 proceeds northeast into the town of Granger before it curves due north to reach the Michigan state line.

[5][6] It wasn't until late 1930 when the SR 23 designation was used again along its modern routing between US 30, in Grovertown and M-62 at the Michigan state line.