Mother tongue of person

Status: This standard was approved as a departmental standard on July 29, 2022.


Mother tongue refers to the first language learned at home in childhood and still understood by the person at the time the data was collected. If the person no longer understands the first language learned, the mother tongue is the second language learned. For a person who learned more than one language at the same time in early childhood, the mother tongue is the language this person spoke most often at home before starting school. The person has more than one mother tongue only if they learned these languages at the same time, and still understands them. For a child who has not yet learned to speak, the mother tongue is the language spoken most often to this child at home. A child who has not yet learned to speak has more than one mother tongue only if these languages are spoken to them equally often so that the child learns these languages at the same time.

Person refers to an individual and is the unit of analysis for most social statistics programs.


'Mother tongue' may be analyzed using the 'List of languages'. Here, if the person reported two or more languages, they are classified using the appropriate 'multiple responses' category. Using this approach, the sum of the count of all categories is equal to the size of the total population. The category, 'none', is not used.

'Mother tongue' may also be analyzed by looking at each language separately. Here, the 'List of languages, total responses' should be referred to. This approach is used to look at all responses of a specific language, regardless of whether or not another language was also reported by the same person.

In this second approach, counts are based on the number of times a language was reported, that is, each instance provided for each mother tongue. Given that a person could have reported more than one mother tongue, the counts for the specific languages cannot be meaningfully combined, as individuals could be included in the count for more than one language. Hence, the sum of the count of all languages could be greater than the total population.

Conformity to relevant internationally recognized standards

A similar variable is suggested in the recommendations for censuses contained in the United Nations' "Principles and Recommendations for Population and Housing Censuses, Revision 3", 2017; however, the definitions differ. The UN defines mother tongue as "the language usually spoken in the individual's home in his or her early childhood". This standard adds the additional criterion that the person still understands the language. The standard also recognizes the possibility of a person having more than one mother tongue, a matter not discussed in the UN recommendations.

The list of languages is based on the international standard ISO 639 presented in the Ethnologue, using those categories that are applicable to the Canadian population and adding supplementary detail on Indigenous languages spoken in Canada.


Relation to previous version

  • Mother tongue of person July 29, 2022 to current

    The definition of 'mother tongue' has been slightly modified.

  • Mother tongue of person September 24, 2021 to July 28, 2022

    The wording of the definition of 'mother tongue' has been modified to specify that a person has two mother tongues if the two languages were learned at the same time, instead of used equally often.

  • Mother tongue of person April 20, 2009 to September 23, 2021

    This is a revision of the previous standard 'Mother tongue'. The definition of mother tongue remains the same but there is a fuller discussion of the question of persons having two mother tongues. The discussion of the alternative approaches to analysis has been added. Previously, there was no standard collapsed classification, users being advised instead to use English and French and the 10 to 15 languages reported with the highest incidence for the given geographic area.

  • Mother tongue July 15, 1998 to April 19, 2009
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