Where to find it
On a TIE card it starts with the letter E followed by digits (e.g. E00000000) and is printed on the front or back of the card.
On the green EU certificate it is the IXESP / C-number reference. On older A4 certificates it may be labelled "Nº de soporte" near the top.
What it is used for
It is required to verify your identity on digital services such as Cl@ve, the immigration portal, and many regional administration websites. Without it, online procedures cannot be completed.
In Ibiza
Most número de soporte requests across the Balearic Islands pass through the Ibiza office. We know exactly what they ask for — and we accompany you, whether you live in central Ibiza or out in Sant Antoni de Portmany.