From today there should be little point in thieves pilfering mobile phones, as they will be next to useless within 24 hours.
A new "blacklisting" system put in place by Vodafone, Telecom and 2degrees means that once a mobile has been reported stolen, it won't work on any of the three networks.
Cyber-safety organisation NetSafe estimated several years ago that about 10,000 mobile phones were stolen in New Zealand each year.
Police Superintendent Steve Christian said the blacklisting system would mean stolen devices would have "no value on the streets".
The phone companies have independently operated their own blacklisting systems for stolen mobiles, however, until now it had been possible for thieves to get around each of the operators' blocks by substituting the Sim card in a stolen mobile with one from a different network.
Blacklisting relies on every mobile phone having a unique 15-digit international mobile equipment identity (IMEI) number, which is silently transmitted to the carrier each time it is used to make a call.
Today, the three mobile operators began sharing their lists of stolen devices with one another and with overseas telcos through an international database.
The phone companies have been working for a year, through the Telecommunications Forum, an industry body, to get the shared system in place.
Stolen smartphones could still be used as wi-fi-only devices or sold overseas and used on networks that didn't check for stolen IMEIs.
But Telecommunications Forum chief executive David Stone said the advance would nevertheless bring real benefits for the community.
"Mobile phones have become more and more important to us over the past few years. For many people, their mobile is not just a phone – it is also their camera, watch, diary, encyclopaedia, map and social organiser.
"This makes smartphones very desirable items, but unfortunately it also makes them a prime target for thieves. The blacklisting system aims to address this problem," he said.
In June, United States prosecutors, concerned about violent thefts of smartphones in the US, suggested phone companies there went one step further and built a "kill switch" into their handsets which would render them completely useless if stolen.