A rebounding Australian job market is behind a renewed loss of Kiwis across the ditch.

For the first time in two years, official figures show the migration flow across the Tasman once again favours Australia.

Figures released on Friday show an annual net outflow to Australia of 66 people. This is the first net outflow since September 2015.

NZIER economist, Christina Leung, says Government policies may have an effect, but it's more down to "the relative performance of the labour market.

"That will determine how many people here in New Zealand would want to look offshore for better job prospects," she said.

Migration to New Zealand from Australia was down 3 per cent from a year earlier, while departures the opposite direction rose 5.2 per cent.