Christchurch has more people sleeping rough, per head of population, than Auckland.

While the number of chronic homeless in Auckland is more than double that of the Garden City, at around 470 - figures show around six in every 10,000 residents in Christchurch are sleeping without shelter.

In Auckland, the figure's just over three for every 10,000 residents.

Christchurch City Missioner Matthew Mark isn't surprised the Christchurch figure is higher.

"Those are the ones who don't have a roof over their heads, so they're sleeping on the sidewalks and in doorways, they're our chronic homeless."

Around five in every 10,000 residents in New York City are sleeping rough, in Sydney it's one in every 10,000.