Auckland renters can expect to pay a minimum $400 a week - regardless of property type or size, according to Trade Me Property's monthly report on median rents across New Zealand.

"Median asking rents in Auckland have rocketed up more than 8 per cent on a year ago," said Trade Me Property head Nigel Jeffries.

"You're now looking at $499 per week for a typical property, taking annual rent costs close to $26,000 - about $2000 more than a year ago. It piles more pressure onto the cost of living for tenants," Mr Jeffries said.

In contrast, Christchurch saw median asking rents continue to decline, down almost 5 per cent on a year ago to $429 per week, and continuing the negative trend of the previous three months.


"The Christchurch rental market was extremely hot two years ago, with asking rents rising more than 13 per cent year-on-year," Mr Jeffries said.

"In March this year it peaked at a weekly rent of $495 to surpass Auckland, but across the remainder of 2015 we've seen rents ease right back and Christchurch tenants are now being asked to pay $3400 less a year."

The Trade Me Property Rental Price Index measures trends in median weekly rents for residential properties on Trade Me Property rented out by real estate property managers and private landlords over the past month. Around 11,000 rental properties are let via Trade Me Property each month.

The figures coincide with surge in Auckland residential rental applications.

Barfoot & Thompson said applications rose 28 per cent last month compared to July, signalling a possible early start to the summer rental season.

Kiri Barfoot, who overseas Barfoot & Thompson's property management services, said the high number of applications was unusual at this time of the year and online rental property searches also rose 26 per cent between July and August.

"This signals an early start to the shifting season, when tenants begin to look elsewhere for properties that might better suit their needs. It's a typical spring trend, but we are seeing it take hold earlier each year as people try and get in ahead of the crowds. It's likely activity will also peak earlier this year - prior to, rather than after, the Christmas holidays," she said.

Feedback from property managers indicated many tenants were thinking ahead to next winter and wanting warm and dry homes.

"Homes with insulation and efficient heating, such as heat pumps are highly sought after and we encourage our landlords to upgrade their properties in this way," she said.

The average weekly rent across Auckland last month increased $4 between July and August, to $496. That is a rise of less than 1 per cent between the two months and just 6 per cent year-on-year, from $467 in August last year.

Barfoots manage more than 13,000 rental properties.