Statistics New Zealand says there will be a rare moment of symmetry on Thursday when the population reaches 4,444,444.
Queensland reached the figure three years ago.
Statistics New Zealand says the milestone resident could be a New Zealander flying home after living overseas or a new migrant, but is most likely to be a new baby.
Population statistics manager Andrea Blackburn says that new boy or girl might even be born at 4.44am.
New Zealand's population reached 3,333,333 in the mid-1980s and based on projections, New Zealand won't get to all the fives for another 30 years.
