Rises in rents are putting extra pressure on low-income earners already struggling with increasing living costs.
Figures from the real-estate firm Barfoot & Thompson and the Trade Me website show that average rents are about $15 a week higher than at this time last year.
Some of the community trusts providing low-cost housing say high rents, especially in Auckland, are putting pressure on their services.
The chief executive of the community housing trust CORT, Peter Jefferies, says people are getting so desperate for accommodation that the trust is having to look at lower-quality housing than in the past - because there is no alternative.
There is a long wait for a Housing New Zealand house, with 10,555 people on the waiting list in May.
'70%' of weekly income to landlord
The chief executive of Mangere Budgeting & Family Support Services, Darryl Evans, says many of their clients are paying about 70% of their weekly income to a landlord.
That means there's little money left to put food on the table, he says.
More families are sharing homes and more people are living in caravans in driveways. Demand is also higher at foodbanks.
Mr Evans says the rise in rent is the difference between a child having breakfast or going to school hungry.
Rents up throughout country
Barfoot & Thompson says average rents in Auckland are $15 higher than at this time last year, at $403 a week.
Trade Me figures show that the average weekly rental has risen nationally by $15 to $380 - an increase of 4% on the June quarter last year.
Trade Me says average rents in Wellington are up 6% to $428. Rents in Christchurch and Dunedin rose by 4% and 5% respectively.