You can hold dual Canadian and British citizenship at the same time. Both Canada and the United Kingdom permit their citizens to acquire another nationality without giving up the one they already have,1Immigration, Refugees and Citizenship Canada. What Is Dual Citizenship2GOV.UK. Dual Citizenship so a Canadian who naturalizes in the UK keeps Canadian status, and a British citizen who naturalizes in Canada keeps British status. What varies is how you get the second citizenship, what happens at the border once you have both passports, and how each tax system treats you.
The One Thing Two Passports Won’t Do
Consular help has a boundary that surprises people. When you are physically inside your other country of citizenship, the government of your first country generally cannot step in on your behalf. The UK states plainly that dual nationals cannot get British diplomatic help while in the other country where they hold citizenship.2GOV.UK. Dual Citizenship Canada gives the same warning: local authorities may be within their rights to block Canadian consular officials from assisting you in your other country of nationality.3Government of Canada. Dual Citizens The country you are standing in has the stronger claim.
How a British Citizen Becomes Canadian
There is no direct route. You first need Canadian permanent residence, usually through Express Entry or a provincial nomination, and only then does the clock start on citizenship.
Physical Presence
You need at least 1,095 days of physical presence in Canada during the five years immediately before you apply. Time spent in Canada as a temporary resident or protected person before you became a permanent resident counts at half value, capped at 365 days.4Department of Justice Canada. Citizenship Act RSC 1985 c C-29 – Section 5 Two years on a work permit before permanent residence, for example, gives you one year of credit toward the 1,095. Immigration, Refugees and Citizenship Canada offers a free online calculator that tallies your days from your travel dates.5Immigration, Refugees and Citizenship Canada. Physical Presence Calculator
Taxes, Language, and Knowledge
You must have filed Canadian income tax returns for at least three tax years falling wholly or partly within the same five-year window.4Department of Justice Canada. Citizenship Act RSC 1985 c C-29 – Section 5 A missed filing is one of the most common reasons applications get delayed.
Applicants aged 18 to 54 must prove speaking and listening ability in English or French at Canadian Language Benchmarks Level 4 or higher,6Immigration, Refugees and Citizenship Canada. Find Out if You Have the Language Proof for Citizenship – Step 1 and must pass a knowledge test on Canadian history, geography, rights, and responsibilities. Applicants under 18 or 55 and older are exempt from both.4Department of Justice Canada. Citizenship Act RSC 1985 c C-29 – Section 5 A serious criminal record or being under a removal order can block the application outright.
Fees, Timeline, and the Oath
The adult application fee totals CAD $649.75, made up of a $530 processing fee and a $119.75 right-of-citizenship fee.7Government of Canada. Pay Your Application Fees Online Current processing runs about 13 months. At the end, you attend a ceremony and swear the Oath of Citizenship, pledging allegiance to King Charles III as King of Canada and promising to observe Canadian law, including the Constitution’s recognition of First Nations, Inuit, and Métis rights.8Government of Canada. The Oath of Citizenship The oath is when you legally become a citizen.
How a Canadian Becomes British
The usual route runs through indefinite leave to remain, the UK’s version of permanent residence. Most Canadians reach it after five years on a qualifying visa.
Residency and the 90-Day Trap
You need at least five years of UK residence before the Home Office receives your application, and you must have held indefinite leave to remain or settled status for at least 12 of those months. Absences over the five years cannot exceed 450 days.9GOV.UK. Apply for Citizenship if You Have Indefinite Leave to Remain or Settled Status A tighter rule applies to the final 12 months: no more than 90 days outside the UK in the year ending on your application date.10GOV.UK. Naturalisation as a British Citizen by Discretion (Accessible) The 90-day rule catches out applicants who travel heavily for work or family.
Life in the UK Test and Good Character
You must pass the Life in the UK test, a computer-based exam on British history, government, and cultural traditions.9GOV.UK. Apply for Citizenship if You Have Indefinite Leave to Remain or Settled Status Applicants 65 and older are exempt, as are those with a long-term physical or mental condition preventing them from taking it.11GOV.UK. Prove Your Knowledge of English for Citizenship and Settling – Exemptions A medical exemption requires a qualified medical professional to complete the exemption form.12GOV.UK. Knowledge of Language and Life in the UK Test Exemption – Long Term Physical or Mental Condition The Home Office also runs a good-character check covering criminal history, financial misconduct, and immigration compliance.
Application, Fees, and Ceremony
You apply on Form AN, online through GOV.UK or by post,13GOV.UK. Apply for Citizenship if You Have Indefinite Leave to Remain or Settled Status – How to Apply and give biometrics at a UK Visa and Citizenship Application Services appointment. Two referees must endorse the application; one must hold a British passport, and neither can be related to you.14GOV.UK. Form UKF – Guidance (Accessible Version) The fee is £1,709 as of April 2026.15GOV.UK. Home Office Immigration and Nationality Fees, 8 April 2026 Most cases are decided within about six months. After approval, you attend a ceremony and swear an oath of allegiance to the monarch along with a pledge of loyalty to the United Kingdom.
The Ancestry Visa Shortcut
A Canadian with a grandparent born in the UK, the Channel Islands, or the Isle of Man can apply for a UK Ancestry visa. You have to be 17 or older, able to support yourself without public funds, and planning to work in the UK.16GOV.UK. UK Ancestry Visa – Eligibility The claim can pass through an adopted parent, and unmarried parents or grandparents do not disqualify you, but step-parents do not count. The visa runs for five years, after which you can apply for indefinite leave to remain, then for citizenship 12 months later.17GOV.UK. UK Ancestry Visa – Overview For families with the right connection, this compresses the timeline significantly.
Passing Citizenship to Children Born Abroad
This is where dual-national families need to plan carefully, because the Canadian and British rules operate independently.
Canada used to impose a first-generation limit: a child born abroad to a Canadian parent who was also born abroad generally did not get Canadian citizenship. Bill C-3, in force on December 15, 2025, removed that restriction.18Parliament of Canada. Bill C-3 An Act to Amend the Citizenship Act (2025) Citizenship can now pass through multiple generations born abroad, provided the chain traces back to an ancestor born or naturalized in Canada. There is a condition, though: if the Canadian parent was born outside Canada and is themselves a citizen by descent, they must have accumulated at least 1,095 days of physical presence in Canada before the child’s birth for citizenship to pass automatically.
On the British side, the British Nationality Act 1981 broadly allows a British citizen by birth or naturalization to pass citizenship to a first-generation child born abroad. A child born abroad to a parent who is British only by descent generally does not automatically acquire citizenship and may need to be registered, subject to specific conditions. Check each child’s status separately under both sets of rules.
Which Passport at Which Border
Two passports do not mean free choice at check-in. To board a flight to Canada, a Canadian citizen (including a dual citizen) must present a valid Canadian passport. Airlines are required to verify this before departure, and a British passport will not get you on the plane.19Government of Canada. Dual Canadian Citizens Need a Valid Canadian Passport A Canadian temporary passport or emergency travel document also works.
From February 25, 2026, the UK requires dual nationals to present a valid British passport, a valid Irish passport, or a foreign passport containing a Certificate of Entitlement confirming right of abode. Airlines must verify this before departure, and British citizens cannot use a UK Electronic Travel Authorisation even if they hold another nationality. Renew an expired British passport before you travel.
Tax in Both Countries
Neither Canada nor the UK taxes purely on citizenship; both look at residency. The question that matters is where you are tax-resident.
If you leave Canada and build your life in the UK, the Canada Revenue Agency generally treats you as a non-resident if you routinely live abroad, lack significant residential ties to Canada, and either live outside Canada for the whole tax year or stay fewer than 183 days. Non-resident status is not tax-free. Canadian-source income you keep receiving, including rent, dividends, CPP, OAS, and RRSP withdrawals, is subject to 25% withholding unless a treaty lowers the rate.20Canada Revenue Agency. Non-Residents of Canada
The UK applies its Statutory Residence Test. Spending 183 days or more in the UK in a tax year makes you automatically resident; very short stays make you automatically non-resident; in between, a sufficient-ties test looks at UK home, family, work, and day count.
The Canada-UK tax treaty limits double taxation. Pensions arising in one country and paid to a resident of the other are generally taxable only where the recipient lives. Dividend withholding is capped at 15% (10% for a company controlling at least 10% of voting power), and interest at 10%.21Government of Canada. Canada-United Kingdom Tax Convention Treaty rates only apply if you inform the payer and claim them; otherwise the full domestic rate is withheld.
Voting Without Naturalizing
A Canadian in the UK does not need British citizenship to vote in UK general elections. As a Commonwealth citizen with permission to stay, whether on a visa, indefinite leave to remain, or settled status, you can register as a parliamentary elector.22Electoral Commission. Can a Commonwealth Citizen Register to Vote Any type of permission qualifies. The right does not extend to overseas voting, and Commonwealth citizens in the UK pending removal are excluded.
Canada is stricter. Only Canadian citizens vote in federal and provincial elections. A British citizen with Canadian permanent residence cannot vote until naturalized. Once you take the oath, you have full voting rights.