- Western Terminus:
- Colonel Rodman Highway (RI 4) in East Greenwich
- Eastern Terminus:
- Roger Williams Way and Commerce Park Road in North Kingstown
- Kent, Washington
RI 403 is a short east/west expressway connecting the Colonel Rodman Highway (RI 4) to Quonset in North Kingstown. It begins at RI 4 about a mile south of I-95 and runs east for a couple of miles before ending at a traffic light at Commerce Park Road, where it turns into Roger Williams Way.