More people arrived on a permanent or long-term basis in March than left, making it only the second month since the earthquake in February last year that the net flow of migrants has been positive.
There was a net inflow of 130 people, Statistics New Zealand said, at least on a seasonally adjusted basis.
The unadjusted number was a net outflow of 1342.
ASB economist Jane Turner said a dip in seasonally adjusted permanent departures appeared to be due to unusually low departures to Europe.
"It is unclear if this is a temporary blip ... or the start of a weaker trend reflecting the economic difficulties in the region."
For the year ended March the country lost a net 3400 people, as arrivals rose 2 per cent to 84,400 but departures rose 15 per cent to 87,800, including 53,200 moving to Australia.
The net loss to Australia was a record 39,500.
Departures to Australia over the past year were a result of the Canterbury earthquakes and the relatively higher unemployment rate on this side of the Tasman, Turner said.
"However, over recent months, Australia's economic recovery has slowed and the labour market has lost some momentum," she said.
"We expect to see an improvement in New Zealand's labour market over the coming year, particularly with the rebuild commencing around the second half of 2012. This should stem the outflow across the Tasman, and potentially attract additional arrivals to meet skill shortages that will arise in the construction industry."
Infometrics economist Matt Nolan expects net migration to recover only gradually over the next 12 months.