New Zealand's four northernmost regions accounted for almost 60 per cent of the country's population growth between 2013 and 2019, Stats NZ says.

These regions – Bay of Plenty, Auckland, Northland, Waikato – collectively grew by 321,400, and are now home to 54 per cent of New Zealand's population.

These are the first subnational population estimates to fully incorporate the 2018 Census and 2018 post-enumeration survey (PES) results.

Estimates back to 2013 have now been revised. This is a normal revision that takes place after census and PES results are available. Estimates after 30 June 2018 now use the 2018-base estimated resident population as the starting-point.

"One of the purposes of running a census is to recalibrate national and sub-national population estimates," population insights senior manager Brooke Theyers says.

"The census coverage results from the 2018 PES, also released today, are crucial to ensure the population estimates are the best possible measure of how many people live in every community across New Zealand."

At the national level, the June 2018 population estimates have been revised up 60,000 (1.2 percent). This revision is spread across New Zealand, with estimates for most areas up slightly, and estimates for some areas down slightly.

"The recalibration of the estimates has generally confirmed the subnational trends evident in the initial population estimates."

Auckland region had the largest population growth, increasing by 187,300 people from 1,493,200 in 2013 to 1,680,500 in 2019. This is equivalent to the population of Dunedin and Invercargill cities combined being added to Auckland over six years. Auckland's average population growth rate was 2.0 per cent a year.

'Although Auckland has the largest population, other regions have seen faster growth since 2013,” Brooke says.

'Net migration drove the growth in these regions which reflected the significant contribution of international migration to New Zealand's overall population growth.”

Bay of Plenty had an average annual growth rate of 2.7 per cent, followed by Northland at 2.4 per cent and Waikato at 2.3 per cent.

Population change is due to both natural increase (births less deaths) and net migration (migrant arrivals less migrant departures).

At the subnational level, net migration includes international migration (movements in and out of New Zealand) and internal migration.