Citizenship and naturalization records

The Canadian Citizenship Act came into force on January 1, 1947. Before this point, Canadians were considered British subjects. People born in other countries could apply to become citizens, a process known as naturalization.

This page lists resources related to citizenship and naturalization records, including how to access them.

Are you looking for proof of citizenship or naturalization?

Most citizenship and naturalization records from 1854 to the present are held at Immigration, Refugees and Citizenship Canada (IRCC). See If you’re looking for proof of citizenship to learn what we have in our collections.

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If you’re looking for proof of citizenship

Start with this database. It includes naturalization lists for 1915–1951, as well as other documents. See About the records for information on the collection.

Supplementary records

If you’re looking for additional records to support your application, we hold the following records:

Census records

In some census years, the country of birth, the year of arrival and the year of naturalization were given by the individual to the enumerator taking the census. For more information on census records, see our General census guide.

Passenger lists

Passenger lists can show when a person arrived in Canada. Information about passenger lists and how to access them can be found on our Passenger lists page.

Birth, marriage and death records

Birth, marriage and death records may help with proving residence. However, you are more likely to find these records in provincial or religious archives. For more information on these types of records, see our guide on Birth, marriage, death and divorce records.

See Access the records below for more information on proof of citizenship documentation.

About the records

LAC holds the following records relating to citizenship.

Naturalization Records, 1828-1850 - Upper Canada and Canada West

In the early 1800s, many people were coming from the United States to settle in Upper Canada (now Ontario). Concerns were raised by authorities about their loyalty to the British monarchy, since most of these new settlers grew up under a republican government. To address this problem, An Act to Secure and Confer upon Certain Inhabitants of this Province the Civil and Political Rights of Natural Born British Subjects was passed in 1828. Under this act, alien men who had been living in Upper Canada for seven years were expected to take an oath of allegiance before the county registrar and thus become British subjects. This was later reduced to five years.

LAC holds 188 registers (RG 5 B47) that include the names of 2,967 individuals naturalized between 1828 and 1850. The registers are available on microfilm reels C-15692 and C-15693.

Most of the registers consist of several pages, usually including an introduction or explanatory text and the schedule of names.

Citizenship registration records, Montreal Circuit Court, 1851 to 1945

These files were created by the Montréal Circuit Court office about people who applied for citizenship. Some files are for people who were born in Canada or Great Britain and became American citizens. 

There are 8,437 files in RG6 F3, volumes 876 to 958.

The files usually provide these details: 

  • name, age and place of birth
  • occupation
  • former and present place of residence
  • number of years residing in Canada

Most of the files include these documents: 

  • petition to be naturalized as a British subject
  • oath of residence and oath of allegiance
  • certificate confirming the oaths were taken

Naturalization lists, 1915 to 1951

These lists include the names of people who were naturalized between 1915 and 1951. They are found in the Canada Gazette and in the annual reports of the Secretary of State. Publishing the lists was required by the Naturalization Act of 1914 and was carried on by later acts.

The lists are digitized and indexed by name. The collection does not include copies of the actual naturalization files. Instead, it provides names and certificate numbers, which can be used to order copies of the actual documents held at IRCC. See IRCC's website for more details on how to obtain copies of the records.

The records were published in different sources across time:

1915 to 1920

Certificates issued from 1915 to 1920 were published together in one report: Report of the Secretary of State of Canada for the year ending March 31, 1920.

The lists are arranged by serial type and serial number. They also include the names of some people who received a certificate after 1914 but who had taken the oath of allegiance years before.

1921 to 1951

From 1921 to March 1932, the lists were published yearly in the Secretary of State’s annual reports.

From April 1932 to April 1951, they were published monthly in the Canada Gazette.

The certificates were listed alphabetically by surname. In some years, there were also supplementary lists added at the end of the main list.

Information about the certificate series

Certificates were issued based on the category of naturalization. Each certificate included a number and a letter, which indicated the series. “French” written after the certificate number meant that it was issued in French rather than English.

Series A to K

Alien” was the term used for a person who was not a British subject (before January 1, 1947) or a Canadian citizen (after January 1, 1947).

  • Series A: Certificates granted to adult aliens
  • Series B: Certificates granted to aliens with minor children included (a minor child was under the age of 18)
  • Series C: Certificates granted to minors
  • Series D: Certificates granted to persons whose nationality as British subjects was in doubt
  • Series E: Certificates granted to persons naturalized under earlier local legislation
  • Series F: Repatriation; certificates granted to persons readmitted to British subject status (no children included)
  • Series G: Repatriation; certificates granted to persons readmitted to British subject status (children included)
  • Series H: Certificates granted to married women whose husbands were naturalized
  • Series I: Certificates of retention granted to married women whose husbands had ceased to be British subjects
  • Series J: Certificates granted to married British-born women whose husbands were enemy aliens (subjects of a country at war with His Majesty)
  • Series K: Certificate granted to persons who had ceased to be British subjects during their minority (under the age of 18) because their fathers had ceased to be British subjects

IRCC has more details about these types of citizenship certificates, particularly how they related to wives and children.

Access the records

Documents from all three collections have been digitized and are accessible in this collection.

The naturalization lists do not include copies of the actual naturalization files. Instead, they provide names and certificate numbers, which can be used to order copies of the actual documents held at IRCC. Find out how to apply for a search of IRCC's citizenship and naturalization records.

IRCC does not currently require certified documentation for proof of citizenship applications if the documents are from the original authority. LAC is considered an original authority for the records it is mandated to hold. In your application to IRCC, you can explain that the documents were received from LAC.

Information on how to submit an application and what documents are required can be found in IRCC’s application instruction guide.

LAC cannot certify documents from other departments.

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2026-07-16