Growing, going, gone: latest numbers show NZ now at risk of population stagnation

A year after the 2023 census, changes were already taking place in New Zealand’s population that meant the data was in danger of being superseded.

Fertility was continuing to decline, the number of immigrants arriving was beginning to climb, there was an exodus of New Zealand citizens, Maori made up more of the population and Asian communities were continuing to grow.

Eighteen months on, we need to revise the picture again. As is often the case with New Zealand, a period of supercharged population growth fuelled by immigration has been followed by a slump.

In the year to February 2024, StatsNZ was reporting immigrant arrivals at an all-time high of 253,200, with a net gain for the year of 130,900.

This surge produced population growth for the 2023 year of 2.3%, compared to the average for all OECD countries of 0.7% . Migration made up more than 85% of this population growth, with natural increase (births minus deaths) the lesser factor.

In 2023, only two OECD countries, Canada and Iceland, exceeded New Zealand’s population growth. Other countries actually saw population decline, notably Germany and Japan.

The latest data shows a major reversal in both immigration numbers and therefore population growth. In the year to September 2025, arrivals were down at 138,900, and the net gain was 12,400.

Population growth was tracking at 0.7%, so the same as the overall average for the OECD.

More are leaving – or not staying

Not only are there fewer arrivals, but the number leaving New Zealand has spiked. Overall, departures are now tracking at 126,400, up 10% on the year before.

What is concerning are the number of New Zealand citizens leaving. For the 12 months to September 2025, 72,700 left, with an overall net loss of 46,400.

The last time we saw such figures was at the back end of the Global Financial Crises in 2011-12. Then, 72,401 New Zealand citizens left, with an overall net loss of 44,385.

But non-New Zealand citizens are also leaving in greater numbers. The 2025 figure is up by 17% on the year before.

It’s most likely that economic circumstances, combined with the opportunities available elsewhere (especially on the other side of the Tasman), are a major contributor to these outflows.

Stagnation, even depopulation

This drop in immigrant numbers, combined with migrant departures, has reinforced an important dynamic – migration is crucial to both the population growth of the country but also that of cities and regions.

In the year to June 2025, natural increase now makes a more significant contribution to population growth (21,000 per year), while net migration is now down at little more than 12,000 per year.

Population growth is now confined largely to the regions with major cities –Auckland, Waikato and Canterbury. Wellington and Taranaki are experiencing population stagnation (no growth), while Nelson, Marlborough, Gisborne and Hawke’s Bay have seen population decline.

Selwyn District remained the fastest growing( 2.4%), while Hamilton was the fastest-growing city (1.4%).

But this is a bit misleading. If Auckland is divided into local boards, then Papakura leads annual growth in New Zealand (2.6%). Henderson-Massey and Howick are also growing at close to 2% per annum.

Overall, low migration means little growth, no growth or population decline for many of New Zealand’s regions and centres. The centres that are growing benefit from both natural increase combined with ongoing immigrant arrivals, albeit at much reduced levels.

Hamilton, for example, has recently gained from immigration (up by 1,900) and natural increase (up by 1,500) despite around 800 people leaving for other parts of New Zealand.

Auckland as the source of internal migration

It’s become a common narrative that people are pouring out of Auckland and contributing to population growth in the rest of the country. There was some truth to this, especially as we emerged from the COVID years and remote working became a thing.

Between 2018 and 2023, 135,000 people left Auckland for other regions. The largest number went to Waikato, followed by Northland and Canterbury.

In the year to June 2023, the net loss from internal migration as people left Auckland for other centres and regions was 11,200. Now that outflow has decreased significantly and is currently tracking at 3,200, a drop of over 70%.

Anticipating what will happen from here is something of a fraught exercise. What we can say is that the elements contributing to population growth, stagnation or depopulation remain volatile.

Paul Spoonley received funding from MBIE to look at New Zealand’s future population as part of a project labelled Nga Tangata Iho Mairangi.