New Zealand's population is about to reach 4.7 million, and we're on track to hit five million in about five years.

Statistics New Zealand estimates there are 4.678 million people currently living in the country.

Senior demographer Kim Dunstan said projections show there'll be more than five million of us by the early 2020s.

But he said at the current rate of growth, it'll be sooner than that.

"We're now outpacing Australia's population growth. Every five minutes our population is currently increasing by one person".

He said the population increased by about 95,000 last year, mostly through migration.

"We had about 65,000 more arrivals than departures and we had about 30,000 more births than deaths".