Social Security Number for Student Workers in Spain

If you have a student visa and plan to work part-time in Spain (up to 20 hours per week during term, full-time during official holiday periods), you will need a numero de afiliacion a la Seguridad Social — your Spanish Social Security number. Your employer cannot legally hire you without one.

This process is separate from your NIE and TIE. It involves a different office (the Tesoreria General de la Seguridad Social) and different paperwork. Here is exactly what to do.

Starting a part-time job in Spain? We help students navigate the Social Security registration and all the admin that comes with working legally. Message us on WhatsApp.

What Is the Numero de Afiliacion (NAF)?

The numero de afiliacion a la Seguridad Social (often abbreviated NAF) is your unique identifier in Spain's Social Security system. It is a number that follows you for your entire working life in Spain and is used to:

• Register you as a worker (alta)
• Track your Social Security contributions (cotizaciones)
• Determine your entitlements (healthcare through employment, unemployment benefits, future pension rights)
• Link you to your employer's payroll system

Important distinction: The NAF is your personal Social Security number. The alta (registration as an active worker) is the act of your employer registering you as employed under that number. You get the NAF first; your employer does the alta.

Do You Need One?

You need a NAF if:

• You have a signed job offer or contract for part-time work
• Your employer is a legal entity in Spain that will pay you through payroll
• You will be working legally under your student visa's work authorization

You do NOT need a NAF if:

• You are not working at all
• You are doing unpaid internships (practicas no remuneradas) — though some internship agreements require Social Security registration even without pay
• You are working freelance/self-employed (autonomo) — that is a different process entirely and has significant restrictions for student visa holders

Requirements

• NIE (your foreigner identification number — on your visa sticker or TIE card)
• Passport (original)
• TIE card (if you have it; otherwise, passport with visa sticker showing your NIE)
• Empadronamiento (certificado de empadronamiento — proof of your Spanish address)
• Work authorization: Your student visa already includes limited work authorization (up to 20 hours/week). Some employers may ask for a separate autorizacion de trabajo — in most cases, the student visa itself is sufficient, but check with your employer.
• Employer information: Your employer's CIF (tax ID number) and company name. Some Tesoreria offices ask for a copy of your work contract or job offer letter.

Step by Step

Step 1: Get a Cita Previa at the Tesoreria General de la Seguridad Social

The Tesoreria General de la Seguridad Social (TGSS) is the office that handles Social Security registrations. It is NOT the same as the Oficina de Extranjeria or the Agencia Tributaria — these are different institutions.

1. Go to the TGSS cita previa website
2. Select your province
3. Choose the service: "Asignacion de Numero de Seguridad Social" or "Afiliacion"
4. Pick a date and time

Tip: Appointments can be scarce in large cities. Try different offices within your province — suburban offices often have earlier availability.

Step 2: Attend Your Appointment

Bring all documents listed in the Requirements section above. Arrive 10-15 minutes early.

The appointment is straightforward:

1. The staff member verifies your identity documents
2. They enter your information into the Social Security system
3. You receive your numero de afiliacion — usually a printed document with your NAF on the spot

Time: 15-20 minutes.

Step 3: Give Your NAF to Your Employer

Once you have your NAF, provide it to your employer along with:

• A copy of your NIE/TIE
• A copy of your passport
• Your bank account details (IBAN) for salary payments

Your employer will then complete your alta (worker registration) before your first day of work. By law, the alta must be processed before you start working — not after.

What Your Employer Handles

Once you give your employer your NAF, they take care of:

• Alta (registration): Registering you as an active worker in the Social Security system
• Cotizaciones (contributions): Paying the employer's share of Social Security contributions and deducting the employee's share from your paycheck
• Baja (deregistration): When your contract ends, deregistering you from the system

You do not need to visit the Tesoreria again for these steps — your employer does it electronically.

Your Social Security Contributions

When you work in Spain, both you and your employer contribute to the Social Security system:

• Employer's share: Approximately 30% of your gross salary (paid by the employer, not deducted from your pay)
• Employee's share: Approximately 6.5% of your gross salary (deducted from your paycheck)

These contributions fund:

• Healthcare (you automatically get public healthcare coverage while employed)
• Unemployment insurance (you may be entitled to unemployment benefits if you lose your job, though eligibility rules apply)
• Pension contributions (these accrue even as a student worker, though you would need many years of contributions for a significant pension)

Common Questions

Can I get the NAF before having a job offer?

In some Tesoreria offices, yes — you can request a NAF "for future employment." In others, they require proof of a job offer or contract. It varies by office and by the individual staff member. If you are job-hunting and want to be prepared, try requesting the NAF proactively. If they refuse, they will tell you to come back with a contract.

What if my employer says they will handle everything?

Some employers offer to handle the NAF request on your behalf. This is technically possible — employers can request a NAF for a new employee. However, it is generally faster and more reliable for you to get the NAF yourself, since you control the timing and documents.

Does my NAF expire?

No. Your NAF is permanent. Once assigned, it is yours for life, even if you leave Spain and return years later. The alta (active worker registration) expires when your contract ends, but the NAF number remains.

What about practicas (internships)?

Paid internships (practicas remuneradas) require Social Security registration — your internship provider handles the alta. Unpaid internships (practicas formativas no remuneradas) may also require Social Security registration under recent regulatory changes, but the process is handled by the educational institution or company, not by you.

Complete admin setup — we handle the appointments. Social Security registration, NIE, empadronamiento — our team guides you through every step. Get in touch.

Timeline

When | Action

When you receive a job offer | Request cita previa at Tesoreria

1-2 weeks later | Attend appointment, receive NAF

Same day | Provide NAF to employer

Before your first workday | Employer completes your alta

Common Mistakes to Avoid

• Starting work before the alta is processed. This is illegal. Your employer must register you before your first day. If they ask you to "start while the paperwork is being processed," this is a red flag.
• Confusing the Tesoreria with the Oficina de Extranjeria. These are different offices. The Tesoreria handles Social Security; Extranjeria handles immigration.
• Not keeping your NAF document. Store it safely — you will need it for your entire working life in Spain. Take a photo and save it digitally.
• Working more than 20 hours/week during term. Your student visa limits you to 20 hours per week during the academic period. Exceeding this can jeopardize your visa status.
• Thinking unpaid work does not need paperwork. Even some unpaid internships now require Social Security coverage. Check with your university's career services.

Complete admin setup — we handle the appointments. From Social Security to NIE to empadronamiento, our team makes Spanish bureaucracy manageable. Start your setup.

Your Social Security number is one piece of the employment puzzle. See also our guides on tax obligations for students in Spain and accessing public healthcare to understand the full picture.