Privacy concerns have been raised over the Wellington City Council asking social housing tenants to provide more information about their income.

Spokesperson Richard Maclean said that they've found a number of people cheating the system.

"This year we've found we've had some tenants that are actually earning more than they should be, and are still staying in our accommodation."

Now the council's asking tenants for three months worth of bank statements to prove they qualify for the reduced rent.

Mr Maclean said the previous way of judging people's eligibility wasn't cutting the mustard.

He doesn't think the new requests infringe on people's privacy.

"We've taken advice as to whether what we're asking for is reasonable in the circumstances, and the Council does have a right to ask for this information from its tenants," Mr Maclean said.