How to Get a NISS in Portugal as a Foreigner

Learn how foreigners can request a NISS in Portugal, what documents are usually needed, how it works with jobs, AIMA, remote work, and Social Security.

A NISS in Portugal is your Social Security Identification Number. Foreigners often need it when they start working, become self-employed, deal with Social Security, or need to prove their situation for some residence-related processes.

The confusing part is that many foreigners hear different answers: some are told they need a work contract first, some are told to apply online, some are told their employer should apply, and some only discover they need a NISS when AIMA asks for Social Security documents.

This guide explains what a NISS is, who can request it, which documents are usually needed, and what to do in common situations like employment, self-employment, remote work, and residence renewal.

Last verified: April 26, 2026. NISS rules, documents, and service channels can change. Always confirm the latest requirements on gov.pt and Segurança Social before applying.

Quick Answer

NISS means: Número de Identificação da Segurança Social.
In English: Social Security Identification Number.
Who issues it: Portuguese Social Security, known as Segurança Social.
Who can request it: Foreign nationals, legal representatives of foreign nationals, and employers on behalf of a foreign national they are going to hire.
Can you apply online? Yes, the official service allows foreigners to apply online.
Does it cost money? The official NISS request is free.
Is it the same as NIF? No. NIF is your tax number. NISS is your Social Security number.
Do all foreigners need one immediately? Not always. It depends on your work, contribution, benefit, and residence situation.

What Is a NISS?

The NISS is the number that identifies you before Portuguese Social Security.

You may need it to:

Work as an employee in Portugal
Register Social Security contributions
Start or manage self-employment obligations
Access some Social Security rights and benefits
Deal with Segurança Social Direta
Handle some residence permit or renewal situations where Social Security information is requested
Prove whether you have Social Security debts in some official processes

Important: A NISS does not give you immigration status, a job, healthcare access by itself, or permission to work. It is an identification number for Social Security.

NIF vs NISS: What Is the Difference?

Foreigners often confuse these two numbers.

Number	Full name	Used for
NIF	Número de Identificação Fiscal	Tax, Finanças, banking, contracts, invoices, IRS
NISS	Número de Identificação da Segurança Social	Social Security, work contributions, some benefits and declarations
SNS user number / Utente	Número de Utente	Public healthcare access through SNS

In simple terms:

NIF = tax number
NISS = Social Security number
Utente number = public healthcare user number

If you are moving to Portugal, you may eventually need all three, but you do not always need them on the same day.

Who Can Apply for a NISS?

According to the official gov.pt service page, the following people can apply for a NISS:

Foreign nationals
Portuguese nationals with a lifetime ID card
Legal representatives of a foreign national
Employers, on behalf of a foreign national they are going to hire

If your employer applies on your behalf, the employer must first sign an employment contract with you and report the employment relationship through Social Security Direct.

If you are starting a job in Portugal, ask your employer whether they will request your NISS or whether you need to request it yourself.

How to Get a NISS in Portugal

There are three common routes.

Option 1: Apply Online Yourself

Foreign nationals can apply online using the official Segurança Social NISS request form. You must fill in the form and attach the required documents.

Option 2: Employer Applies for You

If a Portuguese employer is hiring you, the employer may apply on your behalf. This is connected to your employment contract and the reporting of the employment relationship.

Option 3: Legal Representative Applies for You

A legal representative can apply on your behalf if they have the required authorization and identification documents.

Documents Usually Needed

The exact documents depend on your nationality, work situation, residence situation, and who is applying.

The official gov.pt information says foreign nationals must submit documents in three main areas:

Identification
Work or professional status
Proof of residence permit or residence application situation

1. Identification Documents

For EU, EEA, or Swiss citizens, this may include one of the following valid documents:

National ID document from your country
Passport
Residence card

For third-country nationals, this may include:

Passport
Work visa, if applicable
Residence permit, temporary or permanent, if applicable
Other accepted civil identification document from the country of origin, where accepted

2. Proof of Work or Professional Status

Depending on why you need a NISS, you may need to show one of the following:

Employment contract
Proof of self-employment registration and receipts/invoices
Company registration certificate from IRN
Permanent trading certificate
For digital nomads, proof of an employment contract with an EEA company
Proof of eligibility for voluntary Social Security contributions

The official guidance may require proof connected to your residence situation, such as:

Proof of application for a residence permit
Proof of application for a CPLP residence visa
Proof of application for a CPLP residence authorisation certificate
Residence permit or related accepted document, depending on your situation

Important: Do not assume that informal advice, a relocation company, or a friend’s experience is enough. Bring the strongest documents you have and confirm the current official requirements before applying.

Can You Get a NISS Without a Work Contract?

This is one of the most common questions foreigners ask.

The careful answer is: sometimes, but it depends on why you need the NISS and what proof you can provide.

Official guidance lists several possible reasons or proofs of employment/professional situation, including employment contract, self-employment activity, company registration, digital nomad employment with an EEA company, and voluntary Social Security contribution eligibility.

So a Portuguese employment contract is not the only possible route in every situation, but you normally need to show a valid reason and supporting documents.

Common Examples

Situation	What may happen
You have a Portuguese employment contract	Employer may apply or you may apply with the contract
You are self-employed in Portugal	You may need proof of self-employment registration and receipts/invoices
You are a digital nomad	You may need proof of eligible employment situation, and the details can be strict
You are retired and not working	You may not need a NISS immediately, unless another process asks for it
You need it for AIMA or a residence renewal	You may need to clarify whether AIMA needs a NISS, a Social Security debt certificate, or proof that you do not have Social Security registration

The practical problem is that different offices and situations can lead to different experiences. If you are not working, ask Segurança Social or the relevant office what document they require for your specific case.

Many foreigners only start worrying about NISS when dealing with AIMA, especially during residence card or renewal processes.

The issue is often not simply “having a NISS.” Sometimes the request is about proving your Social Security situation, such as whether you have debts or contributions.

Possible scenarios:

You work in Portugal and have Social Security contributions.
You are self-employed and pay Social Security contributions.
You do not work in Portugal and may not have Social Security contributions.
You have never had a NISS and need proof or clarification of that situation.
The online renewal portal or appointment checklist asks for Social Security-related documents.

Important: If AIMA or another authority asks for Social Security proof, do not guess which document they want. Check the exact wording. It may be a NISS, a declaration of no debt, proof of no registration, or another Social Security document.

Common Catch-22 Problems Foreigners Report

Foreigners often report these situations:

This can happen. Ask the employer whether they can request the NISS on your behalf, because official guidance allows employers to apply for a foreign national they are going to hire.

If you are not required to contribute, you may need to ask which declaration proves your situation. Do not assume that a NISS is always the required document.

The Online Form Asks for Documents I Do Not Have

Your situation may not fit the standard online route. Contact Segurança Social or ask at an official service desk what document is acceptable for your case.

I Applied Online but Need to Collect the NISS in Person

Official information says that after submitting the request, you may receive instructions about collecting the NISS from Social Security services. Bring valid identification when collecting it.

I Am a Remote Worker for a Foreign Company

This can be more complex. Your NISS and Social Security contribution situation may depend on whether you are employed, self-employed, covered by another country’s system, or required to contribute in Portugal. Speak with Segurança Social or a qualified accountant if your income comes from abroad.

Can You Request NIF, NISS, and Utente Number Together?

There is a separate official service for some foreign residents with an address in Portugal to request three numbers together:

NIF
NISS
SNS user number / Utente number

According to gov.pt, this combined request is currently available in selected Espaços Cidadão and is for eligible foreign people with a Portuguese address who meet certain conditions, such as having requested or obtained residence authorization, being an EU national, or having requested international protection.

This combined service may be useful if you qualify, but it is not the same as the normal NISS-only application.

How Much Does It Cost to Get a NISS?

The official NISS request is free.

You may still pay money if:

You hire a lawyer, accountant, or private service provider
You need certified copies, translations, or other supporting documents
You pay someone to help you prepare the application

Be careful with private services that promise fast results without checking your documents.

How Long Does It Take?

There is no single timeline that applies to everyone.

It may depend on:

Whether you apply online or through an employer
Whether your documents are accepted
Whether you need to collect the NISS in person
Office availability
Whether your case is standard or complex

If you urgently need the NISS for work, AIMA, or another deadline, start early and keep proof that you submitted the request.

After You Get Your NISS

After receiving your NISS, keep a copy safely.

You may later need it for:

Employment records
Segurança Social Direta
Social Security contribution checks
Some benefits or declarations
Accountant/tax discussions
Residence permit renewal documents, depending on your case

Also check whether you need access to Segurança Social Direta, the online portal for Social Security services.

Common Mistakes to Avoid

1. Thinking NISS and NIF Are the Same

They are different numbers for different systems.

2. Waiting Until the Last Minute

If you need a NISS for work, residence renewal, or documents, apply early.

3. Uploading Weak or Incomplete Documents

Rejected or delayed applications often happen because the documents do not prove the required situation clearly.

4. Assuming Everyone Needs a NISS Immediately

If you are not working and do not need Social Security services, you may not need it immediately. But some residence processes may still ask for Social Security proof.

5. Not Asking Your Employer

If you are being hired, your employer may be able to apply on your behalf.

For some official processes, the issue may be whether you owe Social Security contributions, not just whether you have a number.

7. Relying Only on Informal Advice

Informal experiences can help you prepare questions, but official requirements can change and may depend on your personal situation.

Practical Tips

Apply early if you expect to work in Portugal.
Save confirmation emails and application references.
Keep copies of all documents you submit.
If an employer is hiring you, ask them whether they will request the NISS.
If you are self-employed, speak with an accountant before assuming your Social Security obligations.
If AIMA asks for Social Security proof, check the exact document requested.
If your case is unusual, ask Segurança Social directly.
Keep your NIF, NISS, and Utente documents organized together.

Summary

A NISS is your Portuguese Social Security Identification Number. Foreigners can request it online, and employers or legal representatives can also apply in some situations. The official request is free, but the documents needed depend on your identity, work situation, and residence situation.

The biggest confusion is not the number itself, but whether you need it for employment, self-employment, remote work, AIMA, or Social Security debt proof. If your case is standard, the process may be simple. If your case involves foreign income, no work contract, expired residence documents, or AIMA renewal, check the exact requirement before applying.