More than 32,000 lost and stolen phones have been blocked over the last year in an effort to make stealing devices less profitable.

Spark, Vodafone and 2Degrees have been working together to block phones across all mobile networks once they are reported lost or stolen.

The blacklist was introduced by the New Zealand Telecommunications Forum (TCF) last December.

It works by blocking a phone’s unique International Mobile Equipment Identity number, which can be found either under the battery, on the original box, or by entering *#06# into your phone’s keypad.

Once a device is blocked on one mobile network it is blocked on all networks nationwide.

The TCF expects that, over time, this service will help reduce the market for stolen mobile phones and the instances of phone theft.

If you are buying a second-hand phone this Christmas, you should check to make sure it hasn’t been reported lost or stolen before you buy.

TCF chief executive Geoff Thorn said it was a good idea to ask for the phone’s IMEI number before buying online.

You can then go to www.MindYourMobile.co.nz and check if it’s on the blacklist. The page has had 54,000 views since it was launched.

If you lose your device, report the loss to your service provider in order to have it blacklisted. If you subsequently find it, the only way to remove the device from the blacklist is to have your service provider do that for you.

The TCF recommends you take note of your IMEI number when you get a new device and store it somewhere safe, just in case your device is lost or stolen in the future.