Twenty-five thousand postcards will be made available free from this week for people to encourage overseas friends and family to vote in the upcoming election.

The cards, available from New Zealand Post shops, remind those overseas of their right to vote in the general election on November 8.

About 50,000 New Zealanders overseas are enrolled to vote, but another 500,000 or so are eligible to.

The cards can be obtained and sent free to any overseas address and are available from Wednesday.