The UK allows dual nationality, so applying for UK dual citizenship simply means applying for British citizenship through the normal route and keeping your existing nationality alongside it — provided your home country also permits it. There is no separate dual citizenship application form. Most adult applicants naturalize, which costs £1,839 in fees as of April 2026 and takes about six months for a decision.
Check Your Home Country First
The UK will not object to you holding two passports. Your country of origin might. Some governments automatically revoke your original citizenship the moment you naturalize elsewhere, and losing that status can mean losing the right to own property, inherit, or work freely back home. China, Japan, India, Singapore, Saudi Arabia, and the United Arab Emirates are among the better-known examples. Austria and the Netherlands restrict dual nationality too, with limited exceptions.
Even countries that allow it sometimes attach conditions, like requiring you to notify authorities or formally register the second nationality. Contact your home country’s embassy or consulate in the UK for a definitive answer before you spend anything on a British application.
Which Route Applies to You
There are three main paths to British citizenship. Naturalization is what most adults living in the UK use. Registration is mainly for children and for people who already hold a form of British nationality and want to convert it. Citizenship by descent covers people born outside the UK to a British parent — and if that applies to you, you may already be a British citizen automatically without needing to apply at all.
Descent normally passes down only one generation. If your British parent was themselves a citizen by descent rather than born or naturalized in the UK, their citizenship generally does not pass to you automatically, though you may still be able to register depending on when you were born.
Naturalization Requirements
The requirement that catches people out: you must already hold Indefinite Leave to Remain (ILR), settled status under the EU Settlement Scheme, or indefinite leave to enter, and you must have held it for at least 12 months before applying. You cannot go straight from a work or family visa to citizenship.
On top of that, you need five years of lawful UK residence before the date your application is received — or three years if you’re married to or in a civil partnership with a British citizen. You must have been physically present in the UK on the exact day five (or three) years before your application arrives at the Home Office.
Absence Limits
Time spent outside the UK during the qualifying period is capped. For the five-year route, no more than 450 days total, and no more than 90 days in the final 12 months. For the three-year spousal route, 270 days total with the same 90-day limit in the last year. Exceeding these caps is one of the most common reasons applications are delayed or refused, so track your travel carefully.
Good Character
The Home Office reviews your criminal record, financial history, and immigration compliance. A conviction doesn’t automatically disqualify you, but unspent convictions, bankruptcy fraud, or a history of immigration violations will normally lead to refusal. Bankruptcy through no fault of your own — a failed business or economic downturn — won’t typically block an application on its own. Deliberate tax evasion or reckless financial behavior is treated much more seriously.
Language and Life in the UK
Most adult applicants must pass two tests. For English, you need at least a B1 level on the Common European Framework in speaking and listening, or you can show a degree taught in English. Nationals of majority English-speaking countries are exempt from the language requirement but still take the Life in the UK test, which covers British customs, history, and laws. Applicants under 18 or aged 65 and over are exempt from both.
What It Costs
As of 8 April 2026:
- Adult naturalization: £1,709 application fee plus a mandatory £130 citizenship ceremony fee, totaling £1,839.
- Child registration: £1,000. If the child turns 18 during processing, the £130 ceremony fee is added.
- Life in the UK test: £50 per attempt, payable each time you sit it.
Fees are non-refundable, including if your application is refused. Budget separately for the English language test if you need one; prices vary by provider. Legal advice is optional but often worth it if your case involves excess absences or past immigration issues.
Documents You’ll Need
Preparing the paperwork is where most of the real work happens. Expect to gather:
- Your current valid passport or Home Office travel document. If you were issued a Biometric Residence Permit, include it even if expired.
- Proof of ILR, settled status, or indefinite leave to enter.
- Evidence of continuous UK residence throughout the qualifying period: utility bills, bank statements, council tax bills, or payslips.
- A detailed list of every trip outside the UK during the qualifying period, with dates and destinations.
- Your English language test certificate, academic qualification, or proof of nationality from a majority English-speaking country.
- Your Life in the UK test pass notification.
- Birth, marriage, or civil partnership certificates as relevant to your route.
Referees
You need declarations from two referees. The first must have professional standing: a solicitor, accountant, minister of religion, civil servant, or member of another recognized professional body. That person cannot also be your immigration representative on the application. The second referee has fewer restrictions but must know you personally. Both confirm your identity and your good character.
Submitting the Application
Most people apply online at GOV.UK. The digital form covers personal details, immigration history, residency and travel, employment, English language, and Life in the UK test confirmation. A paper Form AN is still available for applicants in the Channel Islands, Isle of Man, or British Overseas Territories.
Cross-check every entry against your supporting documents before you submit. Small inconsistencies — a misspelled name, a date off by a digit, a trip you forgot — can trigger requests for further information and add weeks or months to processing. You pay the fee online at submission.
Biometrics
After submitting, you book an appointment at a UK Visa and Citizenship Application Services (UKVCAS) service point to give fingerprints and have your photograph taken. You can upload supporting documents digitally beforehand or have them scanned at the appointment. Nothing needs to be mailed to the Home Office.
What Happens After You Apply
The Home Office typically decides naturalization applications within six months. If yours will take longer, you should be told before the six-month mark. If they ask for additional information, respond promptly, because your delay adds to theirs.
The Citizenship Ceremony
If approved, every adult applicant must attend a citizenship ceremony. You’ll receive an invitation and must book and attend within three months. At the ceremony you make either an oath of allegiance to the King or a secular affirmation, followed by a pledge to respect the rights, freedoms, and laws of the United Kingdom. You leave with your certificate of British citizenship.
Your British Passport
The certificate proves your citizenship, but you’ll need a passport to travel on it. You can apply online for your first British passport roughly 48 hours after the ceremony. Standard processing takes several weeks, so plan around any upcoming travel.
If You’re Refused
A refusal isn’t final. If you think the decision was wrong on law, policy, or procedure, you can request a formal review using Form NR, submitted by post to UK Visas and Immigration in Liverpool. A review fee applies; check the current amount on GOV.UK before sending. The form has no published deadline, but applying promptly strengthens your position. Depending on why you were refused, reapplying after you’ve fixed the underlying issue — waiting out excess absences, clearing tax debts — may be the more practical route.
Which Passport to Use Once You Hold Two
The UK government advises British citizens to enter the UK using a British passport or a certificate of entitlement to the right of abode. Dual nationals with EU settled status may also enter using their foreign passport or national identity card.
Your other country will have its own rule. The United States, for example, legally requires U.S. citizens to enter and leave on a valid U.S. passport, even if they also hold British citizenship. Many countries impose similar requirements. The working rule: enter each country on that country’s passport.
If You’re a US Citizen: Your Tax Obligations Don’t Go Away
This part applies only if you hold both U.S. and British citizenship. The United States taxes its citizens on worldwide income regardless of residence, so becoming British doesn’t change your U.S. filing obligations, and living in the UK doesn’t remove them.
If your foreign financial accounts, including UK bank accounts, pensions, and investments, exceed $10,000 in aggregate at any point in the year, you must file a Report of Foreign Bank and Financial Accounts (FBAR) with FinCEN. The deadline is April 15, with an automatic extension to October 15. Under FATCA, you may also need to file Form 8938 with your tax return: the threshold is $50,000 on the last day of the year or $75,000 at any point for unmarried filers in the U.S., rising to $200,000 and $300,000 respectively for unmarried filers living abroad.
Penalties are steep — $10,000 for failing to file Form 8938, up to $50,000 for continued noncompliance, plus a 40 percent penalty on tax understatements linked to undisclosed assets. The U.S.-UK tax treaty prevents double taxation by letting you credit taxes paid to one country against the other, but you have to claim those credits on your returns. If you fall into this group, a tax professional who works in both systems is worth the fee.