Christchurch is welcoming 22 migrants a day.
Latest figures released by Statistics New Zealand show that last month 564 people arrived in Christchurch from overseas - the highest number in June since records were first published in 1990.
The Philippines was the top source country for migrants, followed by Britain.
Nationally, numbers from China and India also increased.
Most were here to work in the construction and the trades sectors.
Migrant worker Mark Connolly arrived in Christchurch two weeks ago and is already contemplating extending his one-year visa.
Connolly, from County Derry, Northern Ireland, was prompted to look abroad by a lack of work and a suffering Irish economy, and was recruited as a bricklayer by Canstaff.
"I was doing bits and pieces in Ireland but not a lot," he said.
"This is a new challenge and there's a lot of work here to be done."
He arrived alone but found settling in "easy". "The people are friendly and easy going, and it's an easy-going place.
"I've got a visa for a year but to be honest the way things are going and the way things are working out, I could be here for a while," he said.
Hospitality worker Aleisha Higgins has had a similar experience.
She was among many to flock to the city from the Gold Coast in June, after she lost her job in March and spent three fruitless months seeking work in Australia.
After a week of hunting in Christchurch, she had six job offers to choose from.
In the six months to June this year, 3981 permanent or long-term migrants arrived in Christchurch, the equivalent of about 22 migrants each day.
It represents a steady acceleration in migration since late last year.
Migration dropped to an all-time low in June 2011 when only 282 migrants arrived.
However, since last August those numbers have surpassed 520 each month and hit just over 800 in January this year.
Immigration New Zealand settlement support co-ordinator Lana Hart said they had "definitely noticed things picking up".
"But not just in the last month; it's been growing and growing - it's just fascinating," she said.
"Ninety per cent of how it's going is really positive and I'm really relieved to be able to say that, because one year ago we thought just finding a house for a worker would be very hard."
There was a "diverse nature of the group" making Christchurch their new home, with about half bringing families to settle and half coming in search of new lives or to help out with the rebuild.
However, keeping the newcomers in the city was "very much wrapped up in the development of the central business district and the outlying areas", she said.
Acting Canterbury Earthquake Recovery Authority chief executive Warwick Isaacs said job opportunities were driving those seeking work in the construction and the trades sectors to the city.
"I think people are also seeing the chance to be a part of something quite special in Christchurch. It's not often you get to rebuild a city into something new and world class," he said.
The swelling population was also being assisted by a declining number of people fleeing Christchurch.
Only 150 people left Christchurch for Australia in June, the lowest number for any month since November 2009.
However, this could soon change.
University of Canterbury social science lecturer Lyndon Fraser believes that as the Australian economy picks up, New Zealanders will revert to jumping the ditch. Migration patterns were "cyclical, circular and increasingly permanent", he said.
Nationally, there were 88,200 permanent or long-term arrivals in the June 2013 year, up 5 per cent from the June 2012 year (84,400).
564 Migrants arrived in Christchurch in June 2013
449 arrived in June 2012
282 arrived June 2011
480 arrived June 2010
497 arrived June 2009 *
Source: Statistics NZ
- © Fairfax NZ News
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