

An NIE number or Número de Identificación de Extranjero (Foreign Identification Number) is compulsory in all legal and fiscal processes in Spain. This is especially relevant to all who wish to purchase a property or apply for a mortgage in Spain. The NIE number allows the Spanish government to keep track of an individual’s financial & official activity. It is also needed for most bank transactions and to set up all utilities.
The NIE number is composed buy an X followed by 7 digits and a letter. This number will be assigned to you indefinitely.
Banks will not grant a mortgage unless the applicant has a valid NIE number.
Applying for a NIE is simple. All you have to do is present yourself at the Departamento de Extranjeros (foreigners department) of the nearest National Police (policia nacional) station (not the Local Police/policia local) with the following documents:
> Completed and signed original application form and a photocopy (the original will be stamped and returned to you)
> Passport and photocopy
> Address in Spain
> Written justification of why you need the NIE (issued by an accountant, a notary, a bank manager, an insurance agent a future employer, etc.)
You can find more information and a copy of the application form online
here
Once your documentation has been checked, a stamped copy of your application will be handed back to you and you will be told when you need to return to collect your NIE. This can take anything up to 6 weeks so plan ahead. You will be required to present your passport in order for your NIE to be handed to you.
The NIE document is a stamped sheet of A4 paper that will show your name, date of birth and NIE number. We recommend that you immediately make photocopies and keep the original in a safe place.
You can also apply for an NIE at one of the 3 Spanish consulates located in the UK. You can find more information online
here