More New Zealanders are living over 80, and many of them are struggling to make ends meet.

New Auckland University research, funded by the Ministry of Health, shows nine in ten over-80s depend on Superannuation as their main income.

Researcher Ngaire Kerse says it often isn't enough to cover rising rates, rents and household costs.

"Cost of living are also not going down, so the NZ Superannuation also has to keep pace with that."

Ngaire Kerse says women from all backgrounds also have a harder time getting by.

"Men in general have more sources of income from investment than women."

And social housing could soon be out of reach for many Auckland pensioners.

The Ministry of Social Development wants to allow one-bedroom social housing in Auckland to be rented out at up to $400 a week.

Age Concern chief executive Robyn Scott says that would be a tough ask for many over 65s.

She says anyone living primarily on Superannuation or just on Superannuation will find that completely unaffordable.

A one-bedroom social home in Wellington or Christchurch could be cost up to $350 a week.