Apply for a Portuguese Social Security Number (NISS)

What you need to know

The NISS — Número de Identificação de Segurança Social — is the personal 11-digit number that identifies you to Portugal’s Segurança Social (Social Security). Your contributions are recorded under it, and so is your entitlement to unemployment benefit, sickness benefit, and a pension. You need it to work in Portugal, whether as an employee or as a self-employed worker. It is yours for life.

Common situations: which one is yours

The NISS process changes depending on your situation. These are the cases we see most often.

You’ve been hired by a Portuguese company

Your employer can apply for the NISS on your behalf, through Segurança Social Direta, when reporting your hiring. In practice, many companies — especially smaller ones — don’t do this for foreign workers, or leave it until the last minute. If your contract has a set start date, it is worth moving ahead with the application in parallel.

You’ll work as a freelancer or digital nomad

If you are going to work for yourself, you register your activity with the Finanças (the so-called início de atividade) and issue your recibos verdes on the Portal das Finanças, using your NIF. The Finanças reports the start of your activity to the Segurança Social, but as a foreigner you have to apply for the NISS online, attaching a copy of your início de atividade and copies of the receipts or invoices you have issued. If you are a digital nomad with an employment contract with a foreign company, you do not register an activity: the proof of work accepted for the NISS is that contract.

If this is the first time you are registered as self-employed, contributions are only due from the first day of the 12th month after you start your activity — the so-called first-year exemption. You can ask to start contributing earlier, and months without contributions do not count toward your retirement pension. From then on, you file a quarterly income declaration and pay contributions every month.

You’re an EU citizen

You don’t need a residence permit or a visa. If you stay in Portugal for more than three months, you have to apply for the CRUE — the Certificado de Registo de Cidadão da União Europeia (EU citizen registration certificate) — at the câmara municipal (city hall) where you live. For the NISS application, the Segurança Social also accepts your national ID document or your passport, together with proof of work; if you already have the CRUE, attach it to the application.

You’re a non-EU citizen

You need your passport and a document proving your residence status: your residence permit (front and back), a valid residence or work visa — including job-seeker and digital nomad visas — or, if you are still waiting for the card, the receipt for your residence permit application. That receipt is accepted: you don’t have to wait for the physical card to apply for the NISS.

You’re a student starting an internship or a job

Studying in Portugal does not require a NISS. Working or doing a paid internship does — even part-time, even if the internship is short. The rule follows the activity, not your student status.

You’ve worked in Portugal before

If that work was declared to the Segurança Social, you already have a NISS and should not apply for another: registration is for life and any new coverage is linked to the same number, so a second application is unnecessary and only slows things down. Recover the number you already have through Segurança Social Direta, on an old payslip, or at a service desk.

You’ll work as a domestic worker

The general Segurança Social scheme applies, with its own rules: by default, contributions are calculated on a conventional pay figure indexed to the IAS (Indexante dos Apoios Sociais, the social support index) — per hour, per day or, on a full-time monthly contract, an amount equal to the IAS. On a full-time monthly contract, the worker and the employer can agree in writing to pay contributions on the actual salary, never below the minimum wage — which also gives entitlement to unemployment benefit. The NISS is just as mandatory, and the process for getting it is the same.

The mistakes that hold up the process most

Almost every returned application we see falls into one of four cases: illegible or incomplete documents — PDF, JPG, or PNG files up to 3 MB are accepted, but the details must be readable, the edges of the document visible, and the image free of glare, and a two-sided document such as a residence permit is uploaded as two files; missing proof of work — the employment contract already signed, the início de atividade together with the receipts or invoices, or the certidão permanente, as applicable, and not a promise of a job; a self-employed application without a NIF, which the form makes mandatory for that type of application; and a second application from someone who already has a NISS, which does not generate a new number — the NISS is unique. An incomplete application only delays the assignment, and the Segurança Social has no set deadline for assigning a NISS — which is why it pays to get it right the first time.