The Governor-General has issued the formal direction to the Chief Electoral Officer to hold the general election on 8 November.
Anand Satyanand signed the official writ at a ceremony at Government House in Wellington on Wednesday.
The ceremony was the next step in the formal election process, following the dissolution of Parliament on 3 October.
Electoral Rolls closed for printing on 8 October, so anyone enrolled after this date will have to special declaration votes.
Political parties must submit the names of their candidates to the Chief Electoral Office by 14 October, so the printing of about four million ballot papers can begin.
Chief Electoral Officer Robert Peden says half the ballot papers must be ready by 22 October, the day advance voting can begin.
