Those with degree-level qualifications earned significantly more than those with lower qualifications.
Overall, the results were positive for migrants in the New Zealand labour market, the Department of Labour said.
"The information collected from this research provides a unique insight into how quickly and how well migrants are settling into the New Zealand job market and contributing to the economy," said Vasantha Krishnan, Labour and Immigration Research Centre general manager.
"Migrants' early experiences in New Zealand have a significant impact on how well they settle and their ability to make a valuable contribution to society."
Another major finding was that although previous New Zealand work experience seemed important initially, over time, it was not a key factor in employment rates for migrants.
Immigration approval category was also a key determinant of how well migrants participated in the labour force and how much they earned.
At the end of the three-year period, over 90 per cent of primary applicants from the Skilled and Pacific categories, which require a job or job offer to gain residence, were found to be still working.
Principal applicants from the Skilled Migrant Category earned considerably more than migrants from other categories.
This compared with principal applicants from the Pacific category, which had the lowest hourly wages, largely because there was a lower income threshold required on their job offers.
Other key factors considered were age, sex and household composition.
Those migrants who settled in Auckland or Wellington were found to earn more than those who settled in other centres, which broadly reflects differences in wage rates, said the Labour Department.
