How to Get a NISS (Social Security Number) in Portugal

If NIF is the number that unlocks tax and financial life in Portugal, NISS is its counterpart for work and social benefits. Confusingly similar-sounding, entirely different purpose — here's how to sort it out.

What is the NISS?

NISS stands for Número de Identificação da Segurança Social — your personal Social Security identification number in Portugal. It's what links you to the country's social security system: pension contributions, unemployment benefits, sick pay, parental leave, and other social welfare entitlements.

NIF vs. NISS: what's the difference

This is the single most common mix-up for newcomers:

	NIF	NISS
Full name	Número de Identificação Fiscal	Número de Identificação da Segurança Social
Issued by	Autoridade Tributária (tax authority)	Segurança Social
Purpose	Taxes, banking, contracts, utilities, property	Employment contributions, benefits, pensions
Needed for	Almost everything (opening a bank account, signing a lease)	Working legally, freelancing, claiming benefits
Get it before or after moving	Usually first — get your NIF here →	Usually after, once you have a NIF and residence situation sorted

You need both, but they serve different systems and you'll generally get your NIF first since it's a prerequisite for almost everything else, including registering for NISS.

Who needs a NISS

• Employees — your employer typically needs your NISS to register you and make social security contributions
• Freelancers / self-employed (trabalhadores independentes) — required to register and contribute yourself
• Anyone claiming social benefits — unemployment support, family allowance, sickness benefits, pensions, etc.

If you're not working and not claiming any social benefits (for example, a retiree living entirely off foreign pension income with private health insurance), you may not need a NISS immediately — but most people working or planning to work in Portugal will need one.

How to apply

Option 1: In person at a Segurança Social office

1. Book or attend at your local Segurança Social service point (Loja da Segurança Social)
2. Bring the required documents (below)
3. Fill out the registration form (Pedido de Inscrição)
4. Receive your NISS — sometimes issued on the spot, sometimes by post shortly after

Option 2: Online

Portugal's Segurança Social Direta portal allows some categories of applicants to register online, though the online process generally requires you to already have certain credentials or an existing account set up, which can itself be a chicken-and-egg problem for brand-new arrivals. In practice, many expats find the in-person route more reliable for a first registration, especially soon after arrival.

Employer-initiated registration

If you're being hired by a Portuguese company, your employer will often handle NISS registration for you as part of onboarding — confirm with HR whether you already have one or need to apply yourself before your contract starts.

Documents typically needed

• NIF (get it first if you don't have one →)
• Passport or ID card
• Proof of address in Portugal
• Residence permit or CRUE certificate (for non-citizens)
• Employment contract or proof of self-employed activity, if applicable

After you have your NISS

• Give it to your employer for payroll/contribution registration
• If self-employed, register your activity (início de atividade) with Finanças and then set up your independent worker social security contributions
• Keep it alongside your NIF and utente number as one of your core Portuguese ID numbers — you'll need it for job contracts, some benefit applications, and pension record-keeping long-term

FAQ

Can I apply for a NISS before I have a residence permit? Requirements vary by case, but generally you'll need at least a NIF and proof of your situation in Portugal (work offer, residence application in progress, etc.) — check with your local Segurança Social office for your specific circumstances.

Is there a fee to get a NISS? No, registration itself is free.

What if I already worked in another EU country — do I need a new NISS? You still need a Portuguese NISS to work in Portugal, but EU social security coordination rules may let your contribution history transfer or count toward benefits — this is worth discussing with Segurança Social directly if it applies to you.

Can my employer get a NISS for me automatically? In many cases yes, employers can initiate registration for new hires — confirm with HR whether that's already been done before assuming you need to apply yourself.

Do freelancers need to do anything beyond getting a NISS? Yes — self-employed workers also need to formally register their activity (início de atividade) with the tax authority and then arrange their independent worker social security contributions separately.

I lost my NISS number — how do I find it? Check the Segurança Social Direta portal if you have an account, or contact your local Segurança Social office with your NIF and ID to retrieve it.

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Last updated: July 2026.