NIE (Número de Identidad de Extranjero)

Personal, unique and permanent number that Spain assigns to foreigners for any economic or administrative matter: buying a property, opening a bank account, signing up for utilities or paying taxes. Without an NIE you cannot sign the deed or settle the purchase taxes. It is applied for in Spain (at National Police stations, by appointment) or at the Spanish consulate in your country of residence, and it can also be obtained by a representative with power of attorney, common among foreign buyers. It does not expire and does not imply residency: it is only an identifier. It should not be confused with the TIE, the physical card of those who actually reside in Spain, nor with the EU citizen registration certificate.