Housing the homeless could cost taxpayers far less than leaving them to sleep in shelters or on the street.

The Government and Auckland Council are putting $4.7 million towards a new two-year pilot programme to house 472 people.

It will use the Housing First model created by psychologist Dr Sam Tsemberis, which also aims to help people address the reasons they became homeless.

He said supporting an at-risk person could cost $25,000, but not supporting them could cost $200,000.

"People get sick or they get into accidents. They are in emergency rooms, they are in in-patient services. They are transported by the police."

Dr Tsemberis said the long-term solutions to homelessness are more affordable housing and less inequality.

He said the homeless people he's worked with usually want a home, not just a place to spend the night.

"People wanted, when given the choice, a place of their own. A real home. They didn't want to live in a programme. They didn't want to live in special housing."

He said people must stop accepting homelessness as inevitable, and ignoring it when they see it.