text: By country Systems of voter registration vary widely from country to country, and sometimes among lower jurisdictions, such as states or provinces. In some nations, voters are automatically added to the rolls when they reach legal voting age. In others, potential voters are required to apply to be added to the rolls.
  Australia
  Voter registration is compulsory in Australia for all citizens 18 years of age or above. The Australian Electoral Commission maintains Australia's federal electoral roll. Each state also has its own electoral commission or office, but voters need to register only with the AEC, which shares the registration details with the relevant state electoral commission.
  Canada
  In Canada, the National Register of Electors is a continuously updated permanent database of eligible electors for federal elections in Canada maintained by Elections Canada. In the 1990s Canada adopted an opt-in process, by which voters mark their consent to be added the national register on their annual income tax returns.
  The Register is also updated using the following sources:
  provincial and territorial motor vehicle registrars
  Canada Revenue Agency
  Citizenship and Immigration Canada
  provincial and territorial vital statistics registrars, and provincial electoral agencies with permanent lists of electors (e.g. British Columbia and Quebec)
  information supplied by electors when they register to vote or revise their information during and between federal electoral events
  proven electoral lists from other Canadian jurisdictions
  Same-day registration is also permitted.