The NIE: the number you need before anything else moves.

If you are already in Spain, you apply at a National Police station that handles foreigner documentation (Oficina de Extranjería or Comisaría de Policía Nacional). You will need a cita previa (prior appointment), which in popular areas can take weeks to get. If you are outside Spain, you apply at the nearest Spanish consulate — the process is often faster but requirements vary by country. In both cases, you can authorise a representative in Spain to apply on your behalf using a notarised power of attorney (poder notarial).

What you need

• Passport (original + copy)
• Completed EX-15 form (Solicitud de Número de Identidad de Extranjero)
• Proof of reason: pre-contract, bank letter, or property reservation document
• Fee payment (Modelo 790, código 012 — currently around 12 euros)

The NIE assignment is usually immediate once you attend your appointment — you walk out with a provisional certificate the same day. The bottleneck is getting the appointment in the first place. In high-demand areas (Barcelona, Málaga, Alicante, the islands), cita previa slots can be booked weeks in advance. If your property purchase has a deadline, start the NIE process the moment you are serious about buying — not after you find a property.

Timeline to expect

• Cita previa booking: 1 day to 6 weeks depending on location
• Appointment itself: same-day result in most cases
• Via consulate abroad: 2 to 6 weeks depending on country
• Via representative with power of attorney: depends on local availability

Your NIE number is permanent — once assigned, it is yours for life. But the paper certificate (certificado de asignación de NIE) that proves you have one has a validity period, typically 3 months. If your certificate expires before you need it for a notary signing or bank account opening, you may need to request a new one. Some notaries and banks accept expired certificates if they can verify the number independently, but do not count on it.

What to watch

• Keep the original certificate safe — you will need it multiple times
• Check the expiry date and plan your purchase timeline around it
• If buying with a partner, both people need their own NIE
• A gestoría or lawyer can handle renewal if the certificate expires

Many buyers confuse the NIE with a TIE (Tarjeta de Identidad de Extranjero, the physical residency card) or assume they need to become a resident to buy property. You do not. The NIE is a tax identification number, not a residency document. Non-residents buy property in Spain every day. The NIE simply means Spain knows who you are for tax purposes. Separately, if you plan to spend more than 183 days per year in Spain, you will need to register as a tax resident — but that is a different process entirely.

Avoid these

• Do not wait until you have found a property — start the NIE process early
• Do not assume your consulate has the same requirements as another
• Do not confuse the NIE with a residency permit (TIE or tarjeta de residencia)
• Do not let the certificate expire before your notary appointment