However, gaining citizenship in another state is not a walk in the park. Beyond the bureaucratic headache, and varying residency rules and exceptions, some countries may require to give up the nationality of origin as a result of the process.

Few countries in Europe require foreign nationals to do this, but some do. Here is an overview of how the countries covered by The Local deal with dual citizenship, starting with the ones with the strictest rules.

‘Special circumstances’

Austria, Germany and Spain generally do not allow dual citizenship, except in some special circumstances. This means that foreign nationals who obtain the citizenship of one of these countries have to give up their nationality of origin.

Austria

“In principle, anyone who acquires Austrian citizenship by conferral loses their foreign citizenship,” says the Austrian government website. This also applies to Austrian citizens who acquire a foreign citizenship.

Austria only waives the requirement to renounce previous citizenship if this is in the special interest of the state on the basis of “extraordinary achievements” in the past or expected in the future.

Austrians at birth can maintain citizenship if they apply to do so before acquiring another nationality and if this is justified by “special circumstances”, for instance if losing it would have “a severe detrimental impact on their ability to work” or, in the case of minors, if this is in their best interest.

Children with at least one Austrian parent are Austrian and can have dual citizenship. “The child does not have to decide on their (sole) nationality upon reaching the age of majority. However, the other state involved may require them to make such a decision,” the website adds.

Thanks to a recent law, Austrians who left the country before 15 May 1955 because of persecutions by the Nazi regime, and their descendants, can have their citizenship restored and retain any other citizenship they have since acquired.

Germany

At present, only EU and Swiss nationals can retain their citizenship of origin when they naturalise as German – with a few specific carve-outs. For example, children with a German parent acquire German citizenship at birth and can keep dual citizenship permanently. In addition, refugees, people from countries that forbid the renunciation of citizenship and those who were stripped of citizenship during the Nazi period can also retain both passports.

German citizens who wish to naturalise in another country and keep German nationality can apply for a retention permit. In this case they will have to provide evidence of “continuing ties with Germany” and of “substantial reasons” for acquiring the other nationality.

However, an overhaul of these rules is on the horizon, with the German government promising that a “modern citizenship law” will come into force in April 2024. 

This will allow the holding of multiple nationalities and will also see the current residence requirements reduced.

Instead of the current eight years, just five years of continuous residence in Germany will be required in most cases. For people who can demonstrate exceptional integration – including C1 German skills, volunteer work or impressive achievements in their career – citizenship will be attainable after just three years. Currently, the fast-track route to citizenship takes six years and requires B2 German or above.

One rule that will stay the same, however, is naturalisation through marriage: people with a German spouse can naturalise after two years of marriage and a total of three years’ residence in the country.

Spain

As a general rule, people naturalising as Spanish citizens have to renounce their previous nationality. This is not required of nationals of Latin American countries, Andorra, the Philippines, Equatorial Guinea, Portugal, France or Sephardic Jews of Spanish origin (the deadline for the latter to apply for citizenship via this route expired in 2021).

For citizens from these countries the residency requirement to apply for naturalisation is 2 years, but for other nationalities it is 10 years. It is otherwise one year for people married to a Spanish national or 5 years for refugees.

READ ALSO: Do you really have to give up your original nationality if you become Spanish?

Legally speaking, anyone else obtaining Spanish citizenship such as Britons or Americans would need to renounce their original nationality.

The last step in applying for Spanish nationality includes going before a judge to swear allegiance to the Spanish constitution. During this time, they will also ask you to renounce your original nationality.

However, the crucial point is that you will not be requested to physically hand over your other passport, so it will remain in your possession.

The rules for when naturalised Spaniards could lose their Spanish nationality are slightly ambiguous as well (more on that in the link above), but whatever your interpretation, you probably shouldn’t use your non-Spanish passport when travelling into Spain or for other official processes in Spain.

READ ALSO: What are the reasons for losing Spanish nationality and can you get it back?

Dual citizenship permitted

In many other countries, such as France, Italy and Sweden, as well as Belgium, Ireland, Switzerland and the UK, dual citizenship is permitted. 

In France the residency requirement for naturalisation is generally 5 years, showing integration into the French way of life and knowledge of the French language.

In Italy it is possible to apply for citizenship after 10 years of residence, or 4 for EU citizens and 2 for a resident married to an Italian citizen. A language test is also required.

Sweden is one of the few countries where language or civics tests are not needed, although the government plans to change this. The general rule is 5 consecutive years of residence, with absences of more than six weeks during a year subtracted from the total. People married, in a registered partnership or cohabiting partners with a Swedish citizen can apply after three years.

The Swedish government has launched an inquiry to extend the residence requirement to eight years. It’s not yet clear if there will be exceptions for partners of Swedish citizens.

Neighbouring Denmark has one of the strictest citizenship laws. Naturalisation requires an extra waiting period of two years after obtaining a permanent residence permit, which usually takes eight years. There is also a citizenship test.

Denmark allows dual citizenship after the law changed in 2015. Former Danes who lost their citizenship by acquiring a foreign one before September 1st 2015 can reacquire it by making a declaration to the Ministry of Immigration and Integration by June 30th 2026.

After a recent change in regulations, dual citizenship is also allowed in Norway. Those who lost their Norwegian citizenship before 2020 can reacquire it by submitting a notification of citizenship.

There are stricter rules, however, in the Netherlands. Foreign nationals acquiring Dutch citizenship, or Dutch nationals acquiring a foreign one, need to give up their citizenship of origin, except in some specific circumstances – for example, for those acquiring their spouse’s or partner’s citizenship or those holding an asylum residence permit.

Restrictions also exist in many Eastern European countries.

This article was produced by the team at Europe Street news.