Masterton's population grew by 100 during the year ending June 30, according to Statistics New Zealand estimates.
The 0.4 per cent increase brought the estimated population of Masterton to 24,200. Net migration in the 15-39 and 65+ age groups accounted for the increase. The national average regional growth rate was 1.5 per cent.
Carterton was up 2.3 per cent.
Most regions experienced population growth in the past year, due largely to an increase in New Zealand's net gain from permanent and long-term migration, which grew from 7900 in the June 2013 year to 38,300 in the June 2014 year.
"New Zealand experienced a rise in net migration in the June 2014 year because of more people arriving and fewer people leaving the country on a permanent or long-term basis," population statistics manager Vina Cullum said.