Housing NZ has spent $5.8 million so far this year testing and cleaning up state houses contaminated with methamphetamine, and more than half of that has been in Auckland.
The figure released under the Official Information Act shows a rise in the amount spent on decontaminating state houses in the seven months to January compared with previous financial years.
The total amount spent on detecting and cleaning up so-called P houses for 2014/15 was $2.317 million and $711,106 in 2013/14.
Auckland has the biggest issue, with $3.1 million being spent on houses there, followed by $1.01 million in Manawatu/Taranaki/Wairarapa and $357,170 in Christchurch/Nelson/Marlborough.
The least money - $95,423 - was spent on Southland houses.
The amount spent in each region roughly links to figures released by Housing NZ last month which showed 279 homes tested positive for P contamination for the six months of 2015/16 - 113 in Auckland.
The rising costs to taxpayers in sorting out this growing problem comes as a Housing NZ spokeswoman confirmed it was increasing its focus on identifying homes where P has been made or used.
The agency was also cracking down on tenants found to have contaminated their home. Such tenants will not only have their tenancy terminated but will also be suspended from applying for a Housing NZ home for a year.
Housing NZ chief operating officer Paul Commons said having houses contaminated from P use prevents vulnerable people from getting access to a home because cleaning and remediation can take up to three months.
"The use and manufacture of illicit drugs, particularly methamphetamine, is an issue facing societies all around the world - it's not just a Housing NZ problem," he said.
"Methamphetamine use in New Zealand is non discriminatory - it is used by people of all ages, backgrounds and social standing."
The Herald reported last month that the issue was not confined to state houses - homeowners were also paying millions to decontaminate P-riddled properties.
About 40 per cent of homes tested by industry specialist MethSolutions contain traces of P.