Belgium dual citizenship: rules, eligibility and key checks

Adding Belgian nationality to your current passport gives you a permanent foothold in the heart of Europe. Fortunately, Belgium places no requirement on new citizens to renounce their original nationality.

Even though Belgium gives you the green light, your overall path still depends heavily on where you come from. You will want to confirm that your home country allows dual citizenship, map out your eligibility route, and check if any specific loss rules apply to citizens living abroad.

Disclaimer: Belgian authorities decide nationality cases. This guide is not legal, tax, or immigration advice.

Key takeaways

• Belgium generally allows dual or multiple nationality.
• If you are becoming Belgian as an adult, Belgium does not usually ask you to renounce your original nationality.
• Your other country may still restrict dual nationality or treat you only as its own citizen.
• For most expats, the main route is a declaration of acquisition filed through the local municipality or commune.
• Some Belgians born abroad can lose Belgian nationality at 28 if they miss the retention step or the passport or ID safeguard under current rules.
• The key checks are FPS Justice, FPS Foreign Affairs, your commune, and your own embassy or consulate.

Does Belgium allow dual citizenship?

Simply put, yes. Belgium fully permits dual and multiple nationalities, so you will not be asked to give up your current passport when you become a Belgian citizen.

The real catch usually comes from your home country rather than Belgium. Some nations automatically cancel your citizenship if you voluntarily acquire a new passport abroad, making it essential to verify your native country’s rules before applying.

Keep in mind that once you hold dual nationality, local authorities strictly treat you as a Belgian national while you are on Belgian soil, meaning you cannot claim diplomatic protection or consular help from your original home country while living in Belgium.

Who can have dual citizenship in Belgium?

Your route to dual status depends entirely on your current situation. The rules differ slightly whether you are a long-term foreign resident applying for citizenship, a person born with dual nationality, or a Belgian taking another passport. Pinpointing your exact scenario is the best way to understand your options.

If you are becoming Belgian as an adult

For most expats, Belgian citizenship by residence is the main route, usually through a Belgian nationality declaration called a declaration of acquisition once the conditions are met.

The Belgian citizenship requirements still focus on legal residence, knowledge of Dutch, French, or German, and proof of integration or economic participation, depending on the route.

Belgium generally does not require you to renounce your original nationality, but your home country may. Belgian citizenship by marriage is also not automatic, it usually sits within the declaration route after residence and cohabitation.

Before you start, check five things:

• Your residence status
• The correct route
• Your home country rule
• The current official fee
• Your commune’s document list

If you were born with Belgian and another nationality

Some people have dual nationality from birth, for example through a Belgian parent and another parent, or through birth in a country that grants its own nationality.

That situation is different from acquiring Belgian nationality later in life, and older rules or birth dates can matter. If your family history is unusual, check official guidance rather than relying on a general summary.

If you are already Belgian and take another nationality

Current laws make holding two passports very straightforward for Belgian citizens. Anyone who voluntarily acquired a second nationality after April 2008 automatically keeps their Belgian passport without needing to submit extra paperwork or make a formal declaration.

Keep in mind that this rule only applies moving forward. Former citizens who lost their status under the pre-2008 restrictions must go through an official recovery procedure rather than assuming automatic reinstatement.

When can you still lose Belgian citizenship?

Belgium may allow dual citizenship, but that does not mean Belgian nationality can never be lost. The main expat risk is much more specific than many people think, and it mostly concerns some Belgians born abroad rather than adults who become Belgian after residence.

The age-28 rule for Belgians born abroad

Some people born abroad after 1 January 1967 can automatically lose Belgian nationality at 28. The rule mainly applies if all of these points are true:

For example, if you were born in Canada to a Belgian parent, kept Canadian nationality, lived outside Belgium through your twenties, and never renewed a Belgian passport or took a retention step, you could lose Belgian nationality at 28.

If this sounds close to your case, check the Belgian passport guide and your Belgian embassy or consulate before you assume everything is fine.

Other loss, renunciation, or recovery cases

Belgian nationality can also be lost through voluntary renunciation, and in some cases through deprivation linked to fraud or serious misconduct. Recovery exists for some people who lost nationality under older rules, but it is a separate procedure with its own conditions.

If your case involves a minor, statelessness, deprivation, or recovery after an older loss, stop using a general guide at that point. Check the official pages and get specialist advice if the facts are not straightforward.

How to apply for Belgian citizenship and keep another nationality

If you are not sure whether you can keep both nationalities, the safest approach is to check the Belgian rules and your home country’s laws separately.

The prosecutor has up to four months to object once your complete file is acknowledged, though overall processing time depends on document quality and local workload. You can consult FPS Justice for the Belgian application process, FPS Foreign Affairs for loss and retention rules, and your own embassy or consulate for your home country’s regulations.

Documents, fees, and where to apply

Gathering your paperwork requires careful planning, as exact requirements depend on your individual situation. You will generally need core personal documents like your birth certificate, valid identification, proof of continuous legal residence, and evidence of language skills or social integration.

You submit your complete file directly to your local town hall. Foreign certificates usually require official translation and legalisation before your commune will accept them, so requesting a precise checklist from your municipal office prevents wasted effort. If you need to cover translation fees or administrative costs from abroad, multi-currency accounts can simplify your euro transactions.

What dual citizenship means in practice for expats

Holding two passports brings great flexibility, but it also means navigating two sets of legal obligations. Belgian law only governs your status within Belgium, leaving your home country free to apply its own rules.

While you reside on Belgian soil, local authorities view you exclusively as a Belgian citizen. Your other country will still enforce its own passport, consular, and administrative requirements whenever you deal with their officials. Keep in mind that tax residence operates under entirely separate rules, so acquiring a second passport will not automatically change your tax situation.

Topic	What Belgium says	What you should verify
Passport use	Belgian authorities treat you as Belgian in Belgium	Which passport your other country expects you to use when entering or leaving
Consular help	A Belgian who is in Belgium is dealt with as a Belgian	Whether your other nationality limits outside consular support in specific situations
Nationality retention	Belgium generally allows dual nationality	Whether your other country allows it or attaches conditions

Keep copies of both passports or ID documents and renew them on time. If you live abroad, stay alert to any retention rules and to the practical advice from your Belgian embassy or consulate.

Useful resources

Information checked 1st August 2026

• FPS Justice on adult dual citizenship – The primary source for official rules on retaining your original nationality when becoming Belgian
• FPS Justice on declaration of acquisition – Essential details on the formal application process, including fees and legal residence requirements
• FPS Foreign Affairs on losing, retaining, and regaining Belgian citizenship – Critical guidance on understanding citizenship risks and retention requirements, especially for those living abroad
• Belgian embassies and consulates – A directory to find your nearest office for specific, personalized support