The NIE number is a tax identification number in Spain, known in Spanish as the NIE, or more formally the Número de Identidad de Extranjero. Spanish Royal Decree 2393/2004 states that an NIE is required for the purchase or sale of property in Spain, for vehicles and boats; or in order to work or study. People living in Spain, or those who intend to spend a good deal of time in Spain, will need an NIE number. The NIE number is issued by the National Police of Spain, and we can arrange for an NIE to be issued for you. If you are buying a property as a couple, both partners will require an NIE in their names.