Canadian citizenship can be acquired by birth outside Canada to a Canadian parent — this is known as citizenship by descent. The rules governing citizenship by descent have changed significantly over time, and the most recent major change occurred on December 15, 2025, when Bill C-3 came into force. Under the December 2025 rules, a Canadian parent who was themselves born or adopted outside Canada can pass citizenship to their child born or adopted outside Canada, provided the Canadian parent had at least 1,095 days of physical presence in Canada before the child's birth. This replaced the controversial "first-generation limit" that had applied since 2009 and had been declared unconstitutional by an Ontario court. Understanding which set of rules applies depends on the date of birth and the specific circumstances of the Canadian parent's own citizenship.

For the current rules, the full history of changes, and information on applying for a citizenship certificate as proof of citizenship, refer to the IRCC citizenship rules 2025 page and the IRCC proof of citizenship page.

• Citizenship Act, RSC 1985, c C-29, s 3(1)(b) — citizenship by birth outside Canada to a Canadian parent
• Bill C-3 — An Act to amend the Citizenship Act (2025) — the December 15, 2025 reform removing the first-generation limit and introducing the substantial connection test; in force December 15, 2025
• Citizenship Act, s 3(1)(f) — citizenship by adoption outside Canada by a Canadian parent
• IRCC: Change to citizenship rules in 2025 — canada.ca/citizenship-rules-2025
• IRCC: New citizenship rules for Canadians born or adopted abroad (December 2025) — canada.ca/citizenship-descent-2025-news
• IRCC: Check if you may be a citizen — canada.ca/already-citizen

How citizenship by descent works — the basics

A person born outside Canada to a Canadian citizen parent automatically acquires Canadian citizenship at birth — no application is required to become a citizen. However, the person needs to prove they are a citizen, and the mechanism for doing so is a citizenship certificate. The person does not automatically receive a citizenship certificate — they must apply to IRCC for one. The citizenship certificate is the proof document for persons born abroad; a Canadian passport can also serve as proof of citizenship.

The three eras of citizenship by descent rules

The rules have changed over time — which rules apply depends on the date the person was born abroad:

Pre-April 2009 — unlimited transmission

Before the Citizenship Act amendments that came into force in April 2009, citizenship by descent was transmitted without a generation limit. A person born outside Canada to a Canadian parent who was also born outside Canada could still be a Canadian citizen, regardless of how many generations had lived outside Canada. There was no additional requirement for the Canadian parent to have a connection to Canada.

Persons born before April 17, 2009 under the pre-2009 rules may be citizens, subject to the rules in effect at the time of their birth. The IRCC citizenship eligibility checker can help determine whether a person born before 2009 is already a citizen.

April 2009 – December 14, 2025 — the first-generation limit

From April 17, 2009 to December 14, 2025, the Citizenship Act introduced a first-generation limit: citizenship by descent was limited to the first generation. This meant:

• A child born outside Canada to a Canadian parent who was born in Canada — is a Canadian citizen (first generation)
• A child born outside Canada to a Canadian parent who was also born outside Canada — is NOT automatically a Canadian citizen by descent (second generation outside Canada)

This rule was controversial and drew significant criticism. Many Canadians who lived abroad and had children with a foreign-born Canadian partner found that their children were excluded from Canadian citizenship. The law was challenged in Ontario courts, where key provisions were found to be unconstitutional.

From December 15, 2025 — Bill C-3 and the substantial connection test

On December 15, 2025, Bill C-3 came into force, amending the Citizenship Act to remove the strict first-generation limit and replace it with a substantial connection test. Under the December 2025 rules:

• A child born or adopted outside Canada on or after December 15, 2025 to a Canadian parent who was also born or adopted outside Canada is a Canadian citizen if the Canadian parent had at least 1,095 cumulative days of physical presence in Canada before the child's birth or adoption
• The 1,095 days do not need to be consecutive — they can be accumulated over the parent's lifetime
• Physical presence is established through documentary evidence (passport stamps, tax records, employment records, school records)
• The child's citizenship is still automatic at birth — no application to acquire citizenship is required, but a citizenship certificate is needed as proof

For children born before December 15, 2025 who were excluded by the first-generation limit, the Bill C-3 changes may also restore citizenship retroactively in some cases — refer to the IRCC 2025 rules page for details on who may benefit from the retroactive provisions.

Proving citizenship — the citizenship certificate

A person born outside Canada who is a citizen by descent needs to apply for a citizenship certificate to have documentary proof of their citizenship. The certificate:

• Is the official document confirming Canadian citizenship for persons born or adopted abroad
• Is issued by IRCC after the application and supporting documents are reviewed
• Is required to obtain a Canadian passport for the first time as a person born outside Canada
• Is not the same as a passport — a passport can serve as proof of citizenship but requires a citizenship certificate application first for first-time applicants born outside Canada

For current processing times, fees, and the application guide (Guide CIT 0001), refer to the IRCC proof of citizenship page.

Citizenship by adoption

The citizenship by descent rules also apply to persons adopted outside Canada by a Canadian citizen parent. The December 2025 changes apply equally to adoption — a child adopted outside Canada by a Canadian parent who was also born or adopted outside Canada acquires citizenship if that parent had 1,095 days of physical presence in Canada before the adoption. For the specific adoption rules, refer to the IRCC adoption and citizenship page.

The December 2025 change via Bill C-3 is the most significant reform to citizenship by descent in over 15 years and resolves a situation that affected many Canadian families living internationally. The substantial connection test (1,095 days) is designed to ensure that the chain of Canadian citizenship is connected to a genuine, meaningful connection to Canada — not simply a legal technicality. Persons uncertain whether they qualify as Canadian citizens under the new (or prior) rules should use the IRCC citizenship eligibility checker and, if needed, apply for a citizenship certificate for formal confirmation. Given the complexity of the transitional provisions and the retroactive elements of Bill C-3, persons born before December 15, 2025 who believe they may now qualify as citizens should review the IRCC guidance carefully. For the full rules, transitional provisions, and how to apply for a citizenship certificate, refer to the IRCC citizenship rules 2025 page.