 In conjunction with the National Geographic Database , the National Register of Electors is used to create preliminary voters lists for each electoral district in Canada for each election , byelection , and referendum . Each candidate from each electoral district is given a voters list for that district , which is a subset of the data in the National Register of Electors whose addresses are within the boundaries of the district as defined in the National Geographic Database . That data may only be used for election purposes ; any other use of that data subjects the user to penalties including fines , imprisonment , or both . The voter lists are updated by returning officers based on information received during an election campaign , ultimately resulting in final voters lists being distributed by election day . 
