You apply for a Social Security number online on Import@ss, the portal of the General Treasury of the Social Security, in most cases without an appointment. You need a DNI or NIE, a mobile, an email and your address; without Cl@ve or a certificate, a photo of the document and a selfie will do. If a company hires you, the company applies.
Anyone who comes to Barcelona to work for a few months, even as an intern or freelancer, soon runs into a number nobody had mentioned: the Social Security number. You apply online, it is free and, in most cases, you do not need an appointment. This is what the General Treasury of the Social Security (TGSS) and Barcelona International Welcome, the City Council's website for newcomers, explain.
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What the NUSS is
The Número de la Seguridad Social, or NUSS, is the number by which Spanish Social Security identifies you. It is also called the Número de Afiliación (NAF): according to Social Security's own magazine, one becomes the other on the day you start working for the first time. It is assigned only once and, according to Barcelona International Welcome, it does not expire.
Do not confuse it with the NIE, your foreigner's number, which you request from the Policía Nacional (all covered in the guide to the NIE and its appointment), or with the health card: the health system uses your affiliation number to register your card, but they are different documents.
Who needs it and who applies
You need it to register with Social Security for the first time when you start work, to receive benefits or a pension, and to be issued a health card, which is covered in the guide to the TSI for foreigners. You may already have one without knowing it: anyone who has ever worked in Spain or was covered by the Seguro Escolar, the student insurance scheme, has one.
Who files the application depends on your situation. If a company is going to hire you and you have no number, Social Security says the company must apply. For interns, included in the system since 1 January 2024, the university, company or training centre applies. If you are going to be self-employed, or simply want to have it, you apply yourself.
If you are coming on the digital nomad visa, registering with Social Security is part of the process, and Barcelona International Welcome points out that the number is the step before that registration.
How to apply online
The route is Import@ss, the TGSS portal, under the service Solicitar el Número de la Seguridad Social. You can apply at any time. You are asked for your identification details (DNI or NIE), a mobile number, an email address and your usual address.
When you go in, you choose how to identify yourself. With Cl@ve Permanente, Cl@ve Móvil, an electronic DNI or a digital certificate it is quicker. If you have none of these, which is normal when you have just arrived, you can still do it: you upload a photo of both sides of your DNI or NIE and take a selfie holding the front of the document. What does not work is SMS identification: the portal itself warns that you cannot use it without a NUSS.
Social Security recommends downloading and filling in form TA.1, the application for a Social Security number and change of details, beforehand; Barcelona International Welcome adds that it is compulsory if you apply with an NIE or a non-EU passport. Once the number is assigned, a decision is issued that you can print. The official procedure page gives the TGSS a maximum of 45 days to decide and notify you; if that time passes without an answer, the application is deemed granted.
With an NIE, a passport or a permit
Import@ss mentions a DNI or NIE. Barcelona International Welcome explains what to do depending on where you are from. If you are from the European Union, the European Economic Area or Switzerland, you can apply with your passport, but Social Security may ask for your NIE later, so it recommends getting it first and saving yourself a second application. If you are from outside the EU, you need your passport and the decision granting your residence and work permit in Spain; if you are staying more than six months, you will later need a TIE.
The application can also be filed by someone else on your behalf, with an authorisation signed by you, or by your future employer through the Sistema RED.
What about appointments?
Plenty of people search for an appointment for a Social Security number in Barcelona, so it helps to know how things are split. Social Security's magazine explains that in-person appointments are for pensions and benefits handled by the INSS; for TGSS matters such as affiliation, contributions and debt payments, which is where the number belongs, it says to send your request online. In practice: do not hunt for an appointment, use Import@ss.
If you get stuck, the TGSS has an affiliation and general information line, 901 50 20 50 or 91 541 02 91, Monday to Thursday from 9.00 to 18.00 and on Fridays from 9.00 to 14.30, except public holidays (checked in October 2026 on the TGSS website). For general newcomer questions, Barcelona International Welcome refers you to the city's 010 phone line.
If you already have one and cannot find it
If you have worked in Spain before, your number already exists. On Import@ss you can see it in your personal area or in the Acreditación del Número de la Seguridad Social service, which lets you download a PDF as proof. Here Cl@ve, SMS, an electronic DNI or a certificate do work. It also appears on an old payslip, an employment contract or your vida laboral, the employment history report.
Checked
Checked on 18 October 2026 on the TGSS Import@ss portal (the Solicitar el Número de la Seguridad Social service and the contact page), on the seg-social.es page for the procedure to obtain the number, in Social Security's magazine (articles on the NUSS, from May 2024, and on contact channels, from August 2023) and on Barcelona International Welcome's page Obtaining a Social Security Number (NUSS).
Quick questions
Do I need an appointment to get a Social Security number in Barcelona?
Usually not. Social Security's magazine keeps in-person appointments for pensions and benefits handled by the INSS, and for affiliation it says to send your request online, on Import@ss.
Can I apply without Cl@ve or a digital certificate?
Yes. Import@ss lets you upload a photo of both sides of your DNI or NIE and a selfie holding the front of the document. SMS identification does not work if you do not have a number yet.
How long does it take?
The TGSS has a maximum of 45 days to decide and notify you; if it does not answer in that time, the application is deemed granted.
How do I look up my number if I already have one?
On Import@ss, in your personal area or in the Acreditación del Número de la Seguridad Social service, which gives you a PDF. It also appears on a payslip, a contract or your vida laboral report.