About three million enrolment update packs are in the mail this week in the lead-up to the general election.
The Electoral Enrolment Centre says every registered voter will get a pack with information about the election and a referendum on the voting system.
National manager Murray Wicks says everybody should have their envelope by Wednesday.
People are advised to check to ensure their details are correct.
Mr Wicks says people who do not receive an update pack are not enrolled, and should therefore get in touch with the centre.
