An increasing number of pensioners are struggling so much to make ends meet, they're turning to campgrounds and caravan parks for accommodation.

A quarter of tenants at the Ōtāhuhu Caravan Park are collecting the pension, according to manager Bryan Tan, and the number of people aged 65 and over on the Social Housing Register - formerly known as the Housing NZ waitlist - has nearly doubled in two years.

Merv Pearson, 70, is one of 11 pensioners living at Ōtāhuhu Caravan Park. He rents a caravan for $245 per week because he says his $431 a week pension is not enough for a one-bedroom flat.

"If I had a rental I'd be paying power, maybe water, and a lot more rent. It'd mean not a lot [left over]."

Mr Pearson is not on the Social Housing Register, He said he had little faith he'd get a state home, with the waitlist nearing 500 pensioners, although he did enquire about an Auckland Council senior citizen flat.

"They said, 'Oh, there's a six year waiting list'. I walked out. I said, 'Aren't ya building any more?'!"

Photo: RNZ / Brad White

Mr Tan said he answered more than 35 calls per week from people wanting to live at the Ōtāhuhu Caravan Park, and calls every day from the Ministry of Social Development hoping to place clients there.

MSD said a pensioner in a social home would expect to pay no more than a quarter of their income on rent - about $100 a week.

Deputy chief executive housing Scott Gallacher said MSD "want to ensure everyone in need of safe, secure housing has somewhere to stay in the immediate term".

"Once a person's immediate housing need is met we can start to address their longer-term need through the social housing assessment process, placing them on the Social Housing Register with a priority rating.

"The social housing register is not a time-ranked waitlist - people who have been assessed as having the greatest need will be matched to appropriate housing as a priority.

"In addition to the Social Housing register, we have a suite of Housing Support Products available such as assistance with bond payments and accommodation supplement that can help with other accommodation options such as private rentals, for those who are eligible."