Its routing is within portions of Pierce, Bacon, Appling, and Wayne counties.

The route heads northwest through rural areas until it enters Bacon County.

It continues northwest until it has a very brief concurrency with SR 32, east of Alma.

SR 203 curves to the east, and enters Appling County.

Then, it continues to the east, entering Wayne County, to meet its northern terminus, an intersection with US 84/SR 38, southwest of Jesup.