For many immigrants, including Nigerians, Europe remains one of the top four global destinations for migration, offering opportunities for education, employment, and the prospect of long-term settlement.
A 2024 report from the EU’s migration‑policy platform estimates that over 260,000 Nigerians currently reside in the European Union, highlighting the continent’s growing appeal to those seeking new prospects abroad
For many, obtaining the citizenship of these countries is the ultimate goal, a milestone that promises greater security, mobility, and access to opportunities.
Yet, in some EU nations, achieving this goal is complicated by strict dual‑citizenship restrictions.
These rules prevent individuals from holding multiple nationalities, meaning that migrants may be required to renounce their original citizenship to acquire a new one. Dual‑citizenship restrictions are designed to ensure clear lines of allegiance and accountability, addressing concerns such as taxation, military service, and political rights.
In some nations, culture plays a role, as citizenship is closely tied to national identity and social cohesion, and allowing multiple nationalities is seen as potentially weakening that unity.
Understanding which countries enforce these restrictions and the limitations at stake is therefore crucial for anyone planning to migrate.
Here are the 12 EU countries that restrict or do not allow dual citizenship
A Slovak citizen who voluntarily acquires a foreign nationality without long-term residence abroad generally loses their Slovak citizenship.
Slovakia does make exceptions; dual nationality is tolerated when a person acquires a second nationality by birth. Citizenship acquired automatically through marriage, adoption, or as a minor child may also be recognised without loss of Slovak nationality.
Since an amendment in 2022, Slovak citizens who have lived legally in another country for at least five years before acquiring that country’s citizenship can also retain their Slovak citizenship provided they notify the Ministry of Interior within 90 days and supply documentation of their residence.
In addition, obtaining Slovak citizenship by descent for possible for children born to Slovak parents and some descendants can have Slovak nationality without needing to renounce any other citizenship they hold.
For foreigners seeking Slovak citizenship through naturalisation, the rules are stricter. Typically, an applicant must have had continuous permanent residence in Slovakia for at least eight years or five years if married to a Slovak citizen, demonstrate Slovak language proficiency, show knowledge of Slovak history and society, present a clean criminal record, and prove a stable livelihood before being eligible. In such cases, unless one of the legal exceptions applies, acquiring Slovak citizenship via naturalisation usually means giving up one’s previous nationality.
