The Municipal Register is the administrative register where municipality residents are recorded. Its formation, maintenance, revision and custody corresponds to the respective Town Councils, who must submit the monthly variations that occur in the Municipal register data to the INE. The INE, in fulfilment of its competencies, carries out the appropriate checks that aims at correcting possible errors and duplicates and obtains the population figures for each municipality. The President of the INE, with the favourable report from the Register Council, submits the proposal of official population figures of Spanish municipalities concerning the 1st January of each year to the Government for its approval by Royal Decree, thus declaring official the population figures resulting from the the Municipal Register revision and proceeding with their publication in the Official State Journal.

The operation Official population figures from Spanish municipalities: Revision of the Municipal Register publishes the population figures, referring to the 1st January of each year, at municipal level by sex, province capital, islands... The series began in 1996, the starting point for the current system of register management and whose figures refer to 1st May, with the Revision on 1st January 1998 being the first update to be carried out according to this system.