State Route 283 spurs out of US 101 near Scotia, south of Rio Dell, while carrying US 101 Business from that intersection to the Eel River Bridge.

After crossing the bridge, SR 283 ends and US 101 Business continues north through the center of Rio Dell to US 101 in the northern part of the city.

SR 283 includes the length of the Eel River Bridge, keeping its maintenance to Caltrans.

[5] Except where prefixed with a letter, postmiles were measured on the road as it was when the route was established, based on the alignment that existed at the time, and do not necessarily reflect current mileage.

[1] Segments that remain unconstructed or have been relinquished to local control may be omitted.