The road starts at MS 28 near Taylorsville and travels northeastward.

The section in Smith County was designated as Staff Sergeant Mark Haskin Eaton Memorial Highway in 2011,[1] commemorating a member of the Army Special Forces killed in the Vietnam War.

[6] The highway starts at its T-intersection with MS 28, east of the town of Taylorsville.

[7] It travels to the intersection of CO 15 and CO 33, passing by the unincorporated area of Old Taylorsville.

MS 531 then continues northeastward to CO 99, where it shifts eastward slightly.