Nearly 32,000 New Zealanders left for Australia on a permanent or long-term basis during the year to June - the highest since 1989.
Statistics New Zealand says 35,300 New Zealand citizens headed overseas during the 12-month period, of whom 31,900 went to Australia. The number heading there to live is the highest since 1989 when it reached 33,700.
Overall, the number of people arriving to live in New Zealand - 40,000 during the year to June - is still greater than the number of people leaving.
United Future leader Peter Dunne says skilled migrants are not getting enough help to settle in New Zealand.
Mr Dunne says some of the New Zealanders heading across the Tasman will be migrants who have been battling prejudice and a lack of support services.