The introduction of mobile number portability on 1 April 2007 meant that an increasing number of mobiles will be operating on a different network to that which originally assigned the number. To find out whether a particular number belongs to a specific network provider, one can text the mobile number of interest to 300. It is a free service provided by both Telecom and Vodafone. Reply will be sent to verify whether the number is operating on their network or not.