Newly elected Masterton mayor Lyn Patterson is "thrilled" with Masterton's growth, as shown by census data released on Tuesday.
The data shows the number of people in the region has grown 6.5 per cent, from 38,610 in 2006 to 41,115 this year.
The increase was 0.8 percentage points higher than the national average.
Carterton was the fastest-growing area in the North Island and fourth in the country, increasing its population by 16 per cent to 8235 people.
Masterton's population grew from 22,623 in 2006 to 23,352 this year, while South Wairarapa increased by more than 600 people to 9528.
Mrs Patterson said it showed the region was not slipping back. "We're really thrilled with the positive trend that it's shown. It's all good for the Wairarapa."
More people were moving to the area for a "balanced lifestyle", opting to commute to Wellington for work.
"We would love all those Aucklanders to come in the rural province and enjoy a good lifestyle and a life balance here ...
and pay a tenth of the amount for a lovely home."
Wairarapa's primary production industry was another reason behind the growth, Ms Patterson said. "It's an area that will always provide opportunities for jobs and for business.
"Forestry is extremely important for the Masterton district and will be for the next 10 to 20 years so we would expect that this positive trend would continue."
Carterton mayor Ron Mark told the Times-Age on Tuesday the data was proof the region was growing and naysayers could now "eat their words".
The data showed New Zealand's usually resident population was 4,242,048 in 2013, up from 4,027,947 in 2006 - a 5.3 per cent increase.
Auckland is still the fastest-growing region in the country, with a population that has grown by 110,000 people to 1.42 million people since the last census seven years ago.
Census night data showed all 21 local board areas in Auckland increased in population, and Waitemata, Upper Harbour, Rodney, Howick and Franklin were the fastest-growing areas.
Government statistician Liz MacPherson said Auckland's growth was the equivalent of adding a population the size of Tauranga .
After Auckland, the fastest-growing region was Nelson, followed by Waikato.
Southland turned around its population decline by gaining 2000 people.
Overall, 47 out of 67 council areas grew in population. The fastest growing regions were Selwyn, Queenstown-Lakes District, Waimakariri.
The census data also showed that New Zealand gained 7000 people a year from migration between 2006 and 2013 - less than a third of the 23,000 gained a year between 2001 and 2006.
The population for South Island hit one million for first time, with the North Island population sitting at 3.2 million.
The population of Christchurch has dropped by almost 7000 since the 2010 and 2011 earthquakes - but the number of people living in the Canterbury region has jumped by 17,000.
Apart from Canterbury areas affected by earthquakes, the largest population declines were in Kawerau and Ruapehu.
Despite Labour leader David Cunliffe's claim people were fleeing the regions in droves, Ms MacPherson said the data showed steady population growth in most regions.
Economic Development Minister Steven Joyce said population growth in 15 of the country's 16 regions was hardly a "widespread exodus from the regions".
"Mr Cunliffe claimed people were leaving regions such as Taranaki in droves. This couldn't be further from the truth," Mr Joyce said.
"Taranaki grew by 5.3 per cent between 2006 and 2013 and has 5484 extra people now living in the region."