How British Citizenship Affects Your Other Nationality
Becoming British can end your other nationality, but that is decided by the other country, not by the UK. This guide sets out the UK's position, why a country-by-country list is not something to rely on, and what to ask before you apply.
- Section
- British Citizenship
- Reading time
- 9 min
- Last checked
- 6 February 2026
- Source
- The published Immigration Rules and GOV.UK guidance, linked throughout this guide.
- Rowan does not
- Look at your own case, tell you which route to choose, or say what the Home Office will decide. This guide shows the published rules and where to read them.
In short
- The UK recognises dual nationality and lets British nationals who hold it carry a British passport.
- Whether you keep your other nationality is decided by that country's law, not the UK's.
- The Home Office tells applicants to ask their own country before applying, because it cannot answer for it.
- If your other country still treats you as its citizen, its duties, which may include military service, can still apply to you there.
The UK recognises dual nationality. Whether you keep your other nationality is a question of that country's law, which the Home Office does not answer and which changes. This guide covers what the UK actually says, the kinds of rule other countries have, and the questions to put to your embassy before you apply.
The UK position
The Home Office Form AN guidance says: “The UK recognises dual nationality and allows British nationals who have dual nationality, to hold a British passport.” You can hold British citizenship alongside other nationalities, and the UK does not ask you to give any of them up. See our guide to dual citizenship in the UK.
The same guidance is equally clear about the limits of that: “ not all countries allow dual citizenship and you may therefore lose, or have to give up, your existing nationality in order to become a British citizen”. It tells applicants to seek advice from the country they are already a citizen of before applying, and warns that if that country continues to recognise you as its citizen, you may continue to be subject to the duties of its citizens when you are in its territory, which it says may include obligations to undergo military service.
The question is therefore always about the other country's rules, not the UK's. Nothing the Home Office decides changes them, and the Home Office does not check them for you.
Why we do not publish a country list
Nationality law belongs to each country and changes without warning, and no UK source states it. Germany is the clearest example: until 26 June 2024, a German citizen who naturalised elsewhere normally lost German nationality unless they had first obtained a retention permit. From 27 June 2024, the German Federal Ministry of the Interior says the principle of avoiding multiple citizenship was abandoned and multiple citizenship is generally accepted, and the retention permit requirement was removed. A page that had listed Germany as a country requiring renunciation would have been wrong from that day.
So rather than a list that goes stale silently, the reliable step is the one the Home Office itself names: ask the country you are a citizen of, before you apply.
The kinds of rule countries have
Knowing which pattern to ask about makes the answer easier to get. Broadly, a country’s rule will be one of:
- Multiple nationality accepted. Nothing happens to your existing nationality when you become British.
- Automatic loss. Nationality ends by operation of law at the moment you voluntarily acquire another one. There may be nothing to sign and no notice given.
- Loss unless permission was obtained first. The timing matters: permission usually has to come before the naturalisation, not after.
- A duty to choose. The person keeps both for a period and must then formally elect one.
- A duty to declare or surrender documents. The nationality may end automatically, with a further step required to register that and to hand back a passport.
When you contact the embassy or consulate, ask which of these applies, what the deadline is, and what form the step takes.
India and the Overseas Citizen of India card
India is the case most often asked about. The Indian Citizenship Act does not provide for dual citizenship, so an Indian citizen who acquires another nationality is required to renounce Indian citizenship. For foreign citizenship acquired after 1 June 2010, the Indian government requires an application for a surrender certificate alongside a declaration of renunciation, made through the Ministry of Home Affairs online portal.
In place of dual citizenship, India registers people of Indian origin as Overseas Citizens of India. The Ministry of Home Affairs describes the card as a multi-purpose, multiple-entry, lifelong visa for visiting India. Eligibility runs to former Indian citizens and to their children, grandchildren and great-grandchildren, and to minor children of Indian citizens. Check the current terms with the Indian High Commission, as the rights attached to the card have been changed more than once.
Steps before applying
- Ask the embassy or consulate in writing. Get the current rule, the deadline, and the form the step takes.
- Note when the loss would happen. If a nationality ends automatically, it ends at the ceremony, which is the point at which you become British, not when the application is approved.
- Check whether permission has to come first. Where a country allows retention on application, that application is usually made before the naturalisation.
- Ask what replaces it. Some countries register former citizens for a long-term visa or a residence card.
- Plan travel around it. A naturalisation certificate is not a travel document, and the Home Office says a British citizen cannot enter the UK on a biometric residence permit, an eVisa, an electronic travel authorisation or a citizenship certificate. You will need a British passport or a certificate of entitlement to the right of abode.
After becoming British
If your other country allows dual nationality, nothing further is needed on the UK side. If it does not, the steps it may require are typically:
- Registering the renunciation or loss with that government
- Surrendering the passport, and obtaining a certificate of it
- Applying for whatever long-term visa or card replaces it
On the UK side, the Home Office says that after your ceremony you must destroy any biometric residence permit or biometric residence card you still hold, and that to travel you will need a British passport or a certificate of entitlement to the right of abode.
For country-specific guides, visit our country-specific hub.
Related guides:
- Dual Citizenship in the UK
- British Citizenship for Indian Nationals
- British Citizenship for Bangladeshi Nationals
- Renouncing British Citizenship
- eVisa Guide
- Home Office Contact Guide
For official guidance, see GOV.UK: apply for citizenship with ILR.
Questions and answers
Will I lose my original citizenship if I become British?
Not because of anything the UK does. The Home Office Form AN guidance says the UK recognises dual nationality, but adds that not all countries allow it and you may lose, or have to give up, your existing nationality in order to become British. It tells applicants to seek advice from the country they are already a citizen of before applying.
Does the UK allow dual citizenship?
Yes. The UK fully permits dual (or multiple) citizenship. There is no restriction from the UK side. The question is always whether your other country of nationality allows it.
Which countries do not allow dual citizenship?
This is a question of the other country's law, and it changes. Germany, for example, accepted multiple citizenship generally from 27 June 2024, having previously required most of its citizens to give up German nationality. India has never permitted dual citizenship, and offers the Overseas Citizen of India card instead. Only the country itself can state its current rule, which is why the Home Office tells you to ask it.
Should I check with my embassy before applying?
The Home Office guidance says you should seek advice from the country of which you are a citizen before making your application. It also warns that if that country continues to recognise you as its citizen, you may remain subject to its duties when you are in its territory, which may include military service.
This guide is general information about published immigration rules. It is not advice about an individual application under s.82 Immigration and Asylum Act 1999, and Rowan is not regulated by the Immigration Advice Authority. Immigration rules change several times a year. For advice on a particular situation, contact an adviser authorised by the Immigration Advice Authority or an immigration solicitor. Always check GOV.UK for the authoritative current rules.