The Government has been warned its plan to drug test beneficiaries could cost up to $14 million a year.
It intends testing those who don't get jobs because they fail a test, or won't take one, and cut their benefits if they keep using drugs.
Radio New Zealand reports it has a leaked Ministry of Health memo which says the plan could cost up to $14m and warns that up to 10 percent of beneficiaries could claim they were addicted.
Under the plan, those who are addicted to drugs won't face sanctions if they fail work drug tests and will be offered treatment.
The $14m cost forecast is about double the amount the Government hopes to save by getting more beneficiaries into work.
Social Development Minister Paula Bennett says there's a fine line between recreational drug use and addiction.
"It's about using the right professionals so they can make the decisions as to what is recreational use and addiction," she said.
Ms Bennett says the alternative is to do nothing and let people to continue drawing benefits while they fail to get jobs because they use drugs.
NZN