From there it heads north, cosigning with SR 235, across the Santa Fe River into Bradford County and Brooker.

The route continues north into Union County, passing CR 231A, and regains state road status near SW 78th Street and the Florida Department of Corrections Reception and Medical Center.

A second piece of CR 231 fills the gap in SR 231 between Brooker and south of Lake Butler.

East of Brooker is a third piece looping south off County Road 18 that does not line up with the others, yet was also once known as SR 231.

A final piece begins at SR 100 northwest of Lake Butler and extends north to Olustee, where it crosses US 90 before ending at the shore of Ocean Pond in the Osceola National Forest.