The southern segments southern terminus is a continuation as South Dakota Highway 65 (SD 65) at the South Dakota border, and the northern terminus is at ND 21 west of Flasher.

The northern segments southern terminus is at Interstate 94 (I-94) north of New Salem and the northern terminus is a continuation as County Route 37 (CR 37) at the end of state maintenance in Stanton.

[2] The portion of ND 31 in Sioux County, in the Standing Rock Indian Reservation, divides the Mountain Time Zone to the west and the Central Time Zone to the east.

However, ND 31 passes east of St Gertrude and Raleigh along the rural course outside of the Standing Rock Indian Reservation.

The section north of ND 200A carries a part of the Lewis and Clark Trail, due to the close proximity to the nearby Missouri River.