Conditions that led to last year's rises - including landlords being optimistic about getting more rent and high levels of domestic and international migration - would continue this year, they said.
Auckland's big tenant influx - when 50,000 students start looking for accommodation - is not expected to get into full force until later this month but demand is already outstripping supply in many areas.
Paul Smith, president of Auckland University Students Association, said he knew of one Grafton house where about 95 students applied for a single room advertised at $160 a week.
"It's pretty tough in January and February every year, as rent contracts expire and landlords decide to put the rent up," he said.
It's not just students looking for cheap homes. New migrants, families looking to move into better school zones and employees who have moved to Auckland for a new job are also adding to demand. Fifteen people rushed through one Epsom property during a 10-minute "open home" last week in the hope of securing the three-bedroom home that's going for $725 a week in the Auckland Grammar zone.
Rent Me Rentals director Lynda Taylor said Auckland had such a shortage of rental properties that landlords did not always need to list places to get tenants.
"I'm managing to rent places without advertising them," she said, citing people based overseas keen to get a place before arriving in Auckland.
A two-bedroom Devonport home advertised for $500 was rented for $550 a week after the tenant decided he was so keen that he would pay over the asking price, she said.
Salvation Army social policy analyst Alan Johnson said Auckland rent rises during the past two years were hard on people because wages and incomes had not risen by that much.
He knew of one Manurewa household whose rent jumped from $380 a week to $500 in 18 months. Two families and up to 10 people were squeezed in with one bathroom.
Shamubeel Eaqub, NZIER principal economist, agreed strong migration figures could have an effect but questioned how far rents could go. "I don't think rents will rise a lot this year. It tends to be most correlated with incomes which are only growing for a few occupations, not broad-based across the community."
Rent rises worry Community Housing Aotearoa director Scott Figenshow. "Incomes have not gone up to a point that they will be able to afford more, particularly low and moderate income people," he said.
A Barfoot survey last year showed two-thirds of landlords intended to raise their rents.
Pressure on as students return
Auckland student Paul Smith pays $215 a week for a bedroom in an inner-city apartment but may shift further out of the CBD to lower his rent to $170 to $180 a week.
Student Paul Smith.
Mr Smith, president of the Auckland University Students Association, says rent rises are making it tough for students.
"This is expensive, where I am," he said of the CBD apartment. "I'll probably end up in one of the inner-city suburbs in more like a house," he said, expecting rents to rise as students return to study. He knows of one Grafton house where about 95 students applied for a single room advertised at $160 a week.
"It's pretty tough in January and February every year, as rent contracts expire and landlords decide to put the rent up," he said.
Some of his friends were finding flat-hunting hard going.
