What is a Spanish N.I.E Number?
N.I.E. means Numero Identificacion Extranjero (Tax Identification Number for Foreigners in Spain), and it is needed for everything that involves an official process in Spain, such as: buying property, working in Spain, buying a car, contracting electricity and water, getting a telephone line, filing tax returns, starting a business, etc. It is basically a tax number so that the tax authorities can identify an individual when they wish to carry out any economic or financial activity in Spain.
Each individual must have a NIE number. Once you get one, it remains the same forever. It will never change.
If you are thinking of buying a property in Spain, the first step would be to get your NIE Certificate with your Identification number.
This NIE Certificate is compulsory when buying a property and when paying the transfer taxes. It will be requested by the Public Notary and the Land Registry. Therefore, you will need an NIE number before you can complete the purchase (in time for the signing of the Purchase deeds before the notary). Without it, you cannot purchase a property.
It is also required to pay any future taxes in Spain. The Spanish tax authorities are unable to process or accept annual tax payments without an NIE number.