The Social Development Minister Anne Tolley has defended her department after a report showed people were missing out on $200 million in benefit entitlements a year.
The figures were in a report obtained by Newsub's The Nation under the Official Information Act.
It showed 150,000 beneficiaries and low income families were not getting payments totalling $200m a year that they were entitled to.
The report said that was because some people found it difficult to claim entitlements.
In some cases, such as where people had children in OSCAR after school childcare, ten forms were required to be filled in a year.
In other cases, some people had to leave WINZ offices in order to get back to work on time when appointments ran overtime.
Labour's Carmel Sepuloni told The Nation, the culture that had developed in Work and Income offices under Mrs Tolley's leadership was to blame.
"[WINZ staff are] withholding anything that people are entitled to - they are overstretched.
"We shouldn't need Auckland Action Against Poverty to run workshops to inform people of what they are entitled to"
Ms Sepuloni said that was the role of WINZ staff.
Mrs Tolley said her staff did not withhold money, but she accepted some of the reports' findings.
"I agree at times it's too bureaucratic and we're doing our very best."
Mrs Tolley said 7000 WINZ staff dealt with 1,700,000 beneficiaries and the system they were working with was very complicated.