Registering with Seguridad Social
You need a social security number to work in Spain, and being registered is what ordinarily gives you and your family access to public healthcare. The process is short — the confusion is over who does what, and how a number differs from being actively registered.
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Not legal advice. This page explains how registration with Spanish Social Security generally works in general terms so you know what to expect. It is not legal, tax or immigration advice, and it cannot account for your situation. Entitlement to healthcare and benefits depends on your nationality, your work situation and international agreements that may apply to you. Confirm anything that matters with the official body or a qualified gestor or abogado before you act on it.
Two different things, constantly confused
Getting this distinction straight removes most of the anxiety around the subject.
| Number (NUSS) | Affiliation (alta) | |
|---|---|---|
| What it is | Your permanent identifier in the system | Your status as actively registered and contributing |
| How often | Issued once, yours for life | Starts and stops with each job or activity |
| Who does it | You, or your employer on your behalf | Your employer — or you, if self-employed |
| If you stop working | Unaffected — it remains yours | Ends (baja) until you start again |
So leaving a job does not cancel your number, and your contribution record stays intact whether or not you are currently affiliated.
Getting the number
If you do not already have one, you request it yourself. It is free, and it is one of the more modernised parts of Spanish administration — the number can usually be requested online through the Social Security portal without an in-person appointment, which is a pleasant contrast to the NIE process.
You will generally need your NIE or TIE and your passport. If the online route does not work for your situation, an appointment at a Social Security office (CAISS) is the fallback.
Do this before you need it. If you are job-hunting, having the number already makes you easier to hire — an employer who must wait for it has a small reason to prefer another candidate.
If you are employed
Your employer registers you, and must do so before you start working. This is their legal obligation. Your contributions are then deducted from your pay automatically, alongside a considerably larger employer contribution that never appears on your payslip.
Two things worth checking rather than assuming:
- That you actually were registered. You can verify your own working life report (informe de vida laboral) through the Social Security portal. It lists every period you have been affiliated. Checking it early is worthwhile — undeclared employment happens, and the person harmed is you, through lost contributions and no sick pay entitlement.
- What your payslip shows. The employee contribution rate and base should appear on it. See the net salary calculator for how that fits with income tax.
If you are self-employed
You register yourself as autónomo, which combines registering for tax purposes with registering in the self-employed social security regime (RETA). That registration brings a monthly contribution obligation that is due whether or not you invoice anything in a given month.
What that costs depends on your forecast earnings under the bracket system introduced by the 2023 reform — the autónomo calculator works out the figure and explains the reconciliation that follows at year end.
Getting into the health system
Being entitled to healthcare and being registered with a doctor are separate steps, and the second does not happen automatically.
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Entitlement
Be covered
Usually through affiliation and contributions, covering you and dependants. Other routes exist — EU coordination rules for pensioners, provisions for students, and residency-based access.
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Registration
Register at your local health centre
Take your documents to the centro de salud for your address. This is where the padrón certificate is typically required — see the empadronamiento guide.
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Result
You are assigned a doctor and issued a health card
The tarjeta sanitaria is issued by your autonomous community, not nationally, so the card and the process differ by region.
Health services are run regionally. Each autonomous community administers its own, so the card, the appointment system and the app you use all differ depending on where you live — and moving region means re-registering.
If you leave Spain
Your contribution record remains. Within the EU, EEA and Switzerland, contribution periods across member states are aggregated for pension purposes, so years worked in Spain still count towards entitlement elsewhere. Outside that, it depends on whether a bilateral agreement exists between Spain and the country concerned.
Download your informe de vida laboral before you go and keep it. Reconstructing a work history years later, across two administrations and possibly two languages, is far harder than saving a PDF now.
Frequently asked questions
What is the difference between a social security number and being affiliated?
The número de la Seguridad Social (NUSS) is your permanent identifier in the system — issued once, yours for life. Affiliation (alta) is the act of being registered as actively working, which your employer does when you start a job and undoes when you leave. You can hold a number without being affiliated, for example between jobs. People often conflate the two and worry that leaving a job cancelled their number; it does not.
Who registers me — me or my employer?
If you are employed, your employer must register you before you start work. This is a legal obligation on them, not a favour. If you do not yet have a social security number they may ask you to obtain it first, which you can do yourself online or at a Social Security office. If you are self-employed you handle your own registration as autónomo, which also brings you into the contribution system.
Does registering give me access to public healthcare?
It is the usual route, yes. Being affiliated and contributing generally entitles you and your dependants to public healthcare. But contributing is not the only route: pensioners covered by EU coordination rules, some students, and people covered under specific residency provisions can also access the system. Once entitled, you still need to register at your local health centre to be assigned a doctor and issued a health card.
What happens to my contributions if I leave Spain?
They stay on your record. Within the EU, EEA and Switzerland, contribution periods in different member states are aggregated when calculating pension entitlement, so time worked in Spain is not lost if you move. Outside the EU it depends on whether a bilateral social security agreement exists between Spain and that country. Either way, keep your own records — reconstructing a work history years later across two administrations is unpleasant.
Do I need a NIE before I can get a social security number?
In practice yes for most people, since the system needs to identify you and foreigners are identified by their NIE. See the NIE guide for that step. The ordering across all of this is genuinely awkward and slightly circular, which is why the section page sets out a sequence that works rather than leaving you to discover the dependencies one refusal at a time.