If you own a pay as you go or prepaid Spanish mobile phone you could lose your mobile number and have to re-register your phone again. In an attempt to prevent terrorists and criminals using anonymous prepaid mobile phones for communication, the Spanish government has issued a decree that any un-registered phones will be disconnected on the 1st of October.
To comply with the new registration law, pay as you go users have to verify their present address through a recent copy of the padron and a copy of their passport. If you presented both those documents at the time of purchasing your prepaid phone as most people will have done, then no further action is required.
However a number of mobile phone users may have just bought a SIM card to put into an unlocked handset. Until recently it was not necessary to provide proof of address for prepaid SIM cards. Any phone number that is not correctly registered on the 1st of October will be switched of. It is believed that a grace period will exist before the telephone numbers are recycled. This is likely to effect residents that are currently out of the country and will not be returning until winter.