The support number (número de soporte) identifies the physical document in your wallet, not you. Your DNI (Spanish national identity) number or your NIE (foreigner identity number) always stays the same, but each card or certificate you are issued has its own support number. Some public bodies ask for it to check that the document you identify yourself with is genuine and valid, above all when you register with Cl@ve or request your Renta reference number. This post is part of our guide to foreigners in Spain: NIE, Social Security and tax.
One point before we start: the law mentions the DNI's support number but does not say where it is printed or what format it has. Nor does it regulate the one on immigration documents. What follows on its position and format comes from the official help pages of the Agencia Tributaria (the Spanish tax agency) and the Cl@ve system, which we cite in each case.
What the support number is
Real Decreto 1553/2005, which regulates the DNI, lists the data the document carries. Besides the holder's details, it includes two items "relating to the Document itself and to the support card": the expiry date and the support number (article 11.2). In other words, the support number identifies the specific card, not the person.
That is why it changes when you are issued a new document, even though your DNI number or NIE stays the same. And that is why it works as a check: whoever knows it should, in principle, have the document in front of them.
Immigration documents have a support number too. The Agencia Tributaria explains where it is on the foreigner card, the residence permit and the EU citizen registration certificate.
Where it is on a DNI
According to the Agencia Tributaria's Cl@ve help, on a DNI the support number is always on the front (the side with the photo) and the label next to it depends on the model:
| DNI model | Where the support number is |
|---|---|
| DNI 4.0 | On the front, under "NUM SOPORTE" |
| DNI 3.0 | On the front, under "NUM SOPORT" |
| Electronic DNI (2006 to 2015) | On the front, under "IDESP" |
That is why it is sometimes called the IDESP: it is the label it had on the first electronic DNI. For older DNIs, the Agencia Tributaria's help does not show a support number.
Where it is on documents with an NIE
The NIE has no support of its own: the support number is that of the document carrying your NIE. The Agencia Tributaria describes it like this:
| Document | Where it is | How to write it |
|---|---|---|
| Foreigner card (TIE) | On the front | The letter E followed by 8 digits, for example E87654321 |
| Residence permit | On the front | The letter E followed by 8 digits, for example E87654321 |
| EU citizen registration certificate, card format | On the back | Write it with a C in front. If it has fewer than 8 digits, pad it with zeros on the left: 9999999 becomes C09999999 |
| Older EU citizen registration certificate, A4 paper | On the front, top right (it is the certificate number) | Same rule for the C and the zeros |
The most common mistake is typing the NIE where the support number goes, or the other way round. The NIE starts and ends with a letter; a foreigner card's support number starts with E and a registration certificate's with C.
If you want to know what each document is, we explain it in what the NIE is and how it differs from the TIE and the green certificate.
What it is asked for
To register with Cl@ve
Cl@ve is the system you use to identify yourself on public bodies' online offices. When you register online with an invitation letter or by video identification, you first type your DNI or NIE and then a detail found only on your document:
- With a DNI: the validity date or, if your DNI is permanent (valid until 01/01/9999), the issue date. Not the support number.
- With an NIE: the support number of your foreigner card, residence permit or EU citizen certificate.
That is how the Agencia Tributaria explains it in its help on requesting the invitation letter. If you register with Cl@ve using a digital certificate or an electronic DNI, the official Cl@ve page says you also enter the document's support number to verify it.
To get your Renta reference number
If you request your Renta (income tax return) reference number with the amount in box 505 of your previous return, the Agencia Tributaria asks for a check detail: with a DNI, the validity date; with an NIE, the document's support number; and if your NIF starts with K, L or M, your date of birth. See how the return works in modelo 100.
If you see "Introduzca soporte válido"
"Introduzca soporte válido" (enter a valid support number) is the message Cl@ve registration shows when the support number does not match your document. Check, in this order:
- that you typed the support number and not the NIE;
- that you added the letter in front (E for the card, C for the registration certificate) and the zeros on the left if your certificate has fewer than eight digits;
- that you are using the document you hold now, not an earlier one;
- that you typed your DNI or NIE as nine characters in a row, with no spaces.
If the error persists, the Agencia Tributaria says you should go to a National Police station (comisaría del Cuerpo Nacional de Policía) so they can review and update your document's details.
