"We've seen sustained high levels of net migration over the last five years," senior population insights manager Brooke Theyers said.
"Annual net migration has ranged between 48,000 and 64,000 since the year ended December 2014. The only previous time it reached these levels was over a much shorter period over 2002 to 2003."
Migrant arrivals rose up eight per cent for the year to 152,200. The largest nationality of arrivals remained returning New Zealanders.
The next largest groups by citizenship were Chinese, Indian and Australia.
A new more accurate methodology for immigration statistics has seen the figures revised since September 2018 - with new estimates for historical data.
Based on actual departures, rather that intentions filled out on arrivals cards, Statistics NZ says it will be 16 months before the data can be considered 100 per cent accurate.
However, confidence in its estimates grows with each month the new system is in place.
Now with a fifth month of real data recorded Stats NZ demographers consider their estimates robust but have included a window of variability for each number.
They estimate that net migration figure of 56,100 could eventually vary by as much as 2.85 per cent (in either direction).