RI General Law 23-27.3-113.3.2 requires a contractor to be registered prior to the approval of a permit issued for work that requires a permit.
RI General Law 23-27.3-113.31 requires a person to be licensed prior to the approval of a permit issued for work that requires a permit for plumbing, mechanical, electrical, and fire alarm work.
Both sections of the RI General Law have a provision that the owner/occupant of a single family dwelling may obtain permits for all work being completed by them on their residence without the need for a contractors registration or professional trade license.