The list contains the municipalities belonging to the Székely Seats in the 19th century, before the administrative reform in Hungary. The Seats were the traditional self-governing territorial units of the Transylvanian Székelys during medieval times.
In the 19th century, before the Hungarian reorganization of administration, this list includes the municipalities that were part of the Székely Seats in Transylvania. During medieval periods, these Seats functioned as self-governing territorial divisions for the Transylvanian Székelys.