A charity working with homeless people says the lack of a government strategy to get people off the street pushes the work on to charities.
There are no official figures of how many people are homeless in New Zealand, but a recent survey in Auckland found about 147 people were sleeping rough.
Lifewise general manager Moira Lawler said there was no national strategy in place to deal with the problem.
"There's no national framework, there's no agreed approach, there's no policy setting, [and] there's no funding setting."
The current welfare system was too hard for those without a home to use, she said.
"Accessing benefits [is] difficult. People find the hoops, the red tape, the constant having to be in contact very difficult, if you don't have the personal wherewithal," she said.
"If you're not sitting in a comfortable lounge by a telephone, then keeping in touch with WINZ, meeting appointments, keeping in touch with the housing register, is very difficult."
An expensive and undersupplied housing market was making the problem worse.
Sam Tsemberis founded the Pathways to Housing scheme in the United States.
The scheme was proving successful, with about 80 percent of people remaining in the accommodation long term, he said.
"We are the system in between the stationary systems and the very mobile homeless person.
"Not only do we bridge the gaps, but we also provide a guarantee, for example, for rent, or a co-signing on the lease, or renting an apartment for someone who has no credit history and then sub-letting it to them."
He agreed traditional welfare systems did not meet the needs of homeless people.
"The entryway into the system, at large, is blocked for people who are homeless, compounded by the fact that there's no way for the system as designed to reach the applicant for a callback."
He also said New Zealand could solve its homelessness problem if it acted now.
"Relative to other cities in North America, where frankly income disparity is higher, you're trending towards trouble, but you are in a position where an intervention now would actually solve the problem rather quickly."