Indiana State Route 331 is a north-south route in north-central Indiana, serving as the main north-south route through Mishawaka and continuing south from there toward Rochester. Indiana Route 331 ends shy of Rochester, but Indiana Route 25 can be used to continue the rest of the way to that locale. The northern end is at a diagonal Indiana Route 23 pointing to the northeast, near Granger, the Michigan state line, and an interchange with the Indiana Toll Road (Interstates 80 and 90).