Four-and-a-half times more people have flooded into Canberra's north rather than south in the year to 2015, data from the Australian Bureau of Statistics has revealed.

Canberra's centre of population has edged 1.6 kilometres further north in the past decade, now resting on the Yarralumla-side banks of Lake Burley Griffin.

Braddon was Canberra's most densely populated suburb, with 4100 people per square kilometre

But Canberra's burgeoning north amassed the biggest increases in population density.

The number of people per square kilometre rose by 530 people in Harrison, 490 in Crace, 270 in Forde and 230 in Franklin.

Nine of the top 10 largest-growing areas were in the north, including Harrison (up by 1600 people), Crace (810), Ngunnawal (590), Casey and Franklin (both 520).

The population density of more than half of Canberra's suburbs is in decline, with the most sizeable decreases recorded in Waramanga (down by 67 people per square kilometre), Fisher (down 59) and Weston (down 54).

Canberra developer Paul O'Donnell said more and more people were drifting north on the favourable winds of government and private-sector investment in the Gungahlin area.

"If government and private sector are spending tens of millions of dollars in places, it's not a bad place to buy yourself an investment property," the POD Projects Group managing director said.

But the shift could also echo the affordability of the high-density housing springing up in the newer suburbs.

Abbie Snowbal, 22, bought her first apartment in Crace last August.

She said the number of apartment buildings going up in northern Canberra had enabled her and her friends to enter the property market at an affordable price.

"Another one of my friends actually moved into the same apartment block and purchased an apartment on the level below. Another one has bought on in Belconnen, another one is moving into the apartments that are going up in Lawson in Bruce, a lot of them are considering it," she said.

She said the level of maintenance her parents' home in Florey required, with its large backyard and multiple bedrooms, made the prospect of buying a detached house unattractive.

"I think [an apartment is] easy to look after, it's affordable, there's often young people around the area you can meet, there's no need for a backyard because they've got nice parks and exercise equipment around, they've got a community garden up the road, the shops are two seconds away. It's easy."

Tanika Fallon, 29, moved into her brand-new townhouse in Franklin two days before her wedding.

She and her husband Nick saw it as a strategic acquisition.

"With the light rail in Franklin it looked like a great investment for our first home and for our future," she said.

"I think it's the promise as opposed to what's already here."

The emerging Molonglo Valley was found to be the fastest-growing area in Australia, with the population exploding by 127 per cent.

The area, which includes the new suburbs of Wright and Coomb, is now populated by 3600, and far exceeded the growth of Australia's next-fastest growing area, Cranbourne East in Melbourne (up 32 per cent).

For the first time in three years, Canberra's growth was on par with the rest of Australia.

The ACT's population grew by 5400 to 390,700.