Census forms go out to households next month and Statistics New Zealand hopes 35% of all returns will be on line.
The last Census was held in 2006. They are supposed to be done every five years, but the 2011 census was deferred because of the Christchurch earthquakes.
Only 7% of completed Census forms were done online in 2006.
Statistics New Zealand is aiming for 35% this year.
The Census will be held on 5 March. Forms can be completed in English or Maori.