The Ministry for Social Development has discovered it could be failing to pay almost half of the tens-of-thousands of beneficiaries the right amount.
This is the latest result from a survey it's been doing into the accuracy of its payments, as it struggles with 30-year-old IT systems that regularly trip its staff up.
In the case of the 43 percent of people not getting what they are entitled to, the ministry does not break that down into those getting too much - versus those getting too little.
Beneficiaries' advocate Kay Brereton spoke to Ingrid Hipkiss.