The Spanish Social Security number: getting one, and who registers you

Affiliation and registration are two different acts

Spanish Social Security law separates two things that English speakers tend to call by the same name. Afiliación, affiliation, is the act by which the General Treasury of Social Security recognises that a person is included in the system, the first time they carry out an activity that brings them in. It happens once. It is single — the same affiliation serves every scheme, whether you are employed, self-employed or both — and it lasts for your whole life.

Alta, registration, is the act by which the Treasury records that you have started a particular activity under a particular scheme. It happens every time you start a job or start working for yourself, and it is matched by a baja, a deregistration, when that activity ends. Two jobs at once means two registrations in the same scheme; working for an employer and for yourself at the same time means registrations in two schemes.

Your Social Security number, número de la Seguridad Social, sometimes called NUSS or NAF, is the number that identifies your affiliation. The Treasury gives every affiliated person, pensioner and beneficiary an identifying document carrying it.

Who asks for the number

Affiliation can be requested by an employer, by the worker, or done by the Treasury on its own initiative. An employer is obliged to request the affiliation of anyone who starts working for them and is not yet affiliated, and that request automatically includes the first registration under the right scheme.

You can also apply for the number yourself before you have a job. That is worth doing if you are about to start work for yourself, because the self-employed registration assumes you already have it. The application goes to the Treasury, on the official form or through its electronic office, with your identity document. For a foreign national that means your passport and NIE, or your TIE or EU registration certificate showing the NIE.

The NIE comes first. Without it there is nothing to attach the affiliation to. If your NIE is being assigned as part of a permit procedure, wait until you have it.

The deadline your employer must meet

The regulation says the registration must be filed before the worker begins to provide services, and never earlier than 60 calendar days before the planned start. Working a first day before being registered is not a formality: it is working without Social Security cover, and the employer is exposed to sanctions.

If the employer does not register you on time, the regulation lets you ask for the registration directly yourself, without prejudice to the employer's own liability. Ask for your working-life report, informe de vida laboral, a few days after starting a job; it lists every registration in your name and is the simplest way to check that yours was filed.

If you work for yourself

Self-employed workers are responsible for their own registration, in the self-employed scheme, and it must also be filed before the activity starts. The special tax regime for new residents counts its six-month deadline from the start date recorded on this registration, so the date matters for more than Social Security.

Where to go

Applications go to the provincial directorate of the General Treasury, or one of its administrations, in the province where the employer is based — or, for the self-employed, where you live or work. Much of it can now be done through the Social Security electronic office, Import@ss, instead.