AIMA and Social Security Clarify Employment of Foreign Citizens Without NISS Number

7 January 2025

On 27th December 2024, Portugal's Social Security announced an important clarification regarding the employment of foreign citizens residing in Portugal. Companies are explicitly allowed to hire foreign workers even if they do not yet possess a Número de Identificação de Segurança Social (NISS), commonly referred to as a Social Security Number.


This clarification acknowledges the practical challenge faced by foreign residents and employers. 


The employment contract is a prerequisite for assigning a NISS number to a foreign citizen. Therefore, the employment contract doesn't need to include the NISS number in the contract itself.


Once the foreign worker has been assigned a NISS number, the employer must report the employment relationship through the Segurança Social Direta (Direct Social Security) online platform of Portuguese Social Security. This procedure ensures the regularisation of tax obligations, specifically the payment of social security contributions.


This clarification from Portuguese Social Security comes at a critical time, as immigration in Portugal has become a significant focus, particularly within the national job market. The primary objectives of this statement are to promote regularisation, facilitate integration, and ensure fair working conditions for foreign workers. Simultaneously, the Portuguese labour market benefits from having these workers regularised, as their contribution is essential to addressing the country’s workforce demands.


One week later, on 4th January 2025, the AIMA agency reinforced this message with a similar announcement through a post on their LinkedIn page.


AIMA's post emphasised that an employment contract is a mandatory requirement to obtain the NISS number. Without a valid employment contract, it is not possible for a foreign citizen to acquire the NISS number. In essence, securing an employment contract is a crucial step before obtaining the NISS.


Once the NISS is assigned by Social Security, the foreign citizen becomes eligible to fulfil the legal obligations established under Law No. 23/2007 with AIMA IP.


This clarification made by these two public entities represents a significant step towards streamlining the immigration process for individuals seeking employment with Portuguese companies. Additionally, it strengthens the Portuguese business landscape by offering clear legal guidance and promoting the integration of these workers into the Portuguese job market.

The NISS number, or Portuguese Social Security Number, serves as a unique identifier for individuals working in Portugal, including employees and self-employed professionals such as freelancers.


The NISS number is utilised for social security and taxation purposes.


Upon acquiring Portuguese citizenship, the NISS number is automatically assigned as part of the process for obtaining the Citizen Card.



If you require assistance with obtaining your NISS or have other inquiries related to Portuguese Social Security processes, don’t hesitate to reach out to us. We are here to provide expert guidance and support.

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