Tennessee law requires that all mechanically powered vessels (including federally documented recreational vessels) and all sailboats which are principally used in Tennessee must be registered. (Boats are not titled in Tennessee.) Mechanical propulsion includes electric trolling motors but does not include boats powered only by oars or paddles. Boats which require registration must be properly registered before using them upon any public water of Tennessee.
Currently registered boats from other states may use Tennessee waters unless Tennessee has become their state of principal use. Exception: Sailboats brought into Tennessee by persons from states that do not require numbering of sailboats are exempt from registration provided that Tennessee is not the state of principal use. State of principal use means the state on whose waters a vessel is used or to be used most, whether moored or underway, during a calendar year.