Cardston County is a municipal district in southern Alberta, Canada. It is located in Census Division 3 around the Town of Cardston.
The municipal district was established on January 1, 1954, through the amalgamation of the Municipal District of Sugar City No. 5 and part of the Municipal District of Cochrane No. 6. On January 1, 2000, the name was changed from Municipal District of Cardston No. 6 to Cardston County
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The following urban municipalities are surrounded by Cardston County.
The following hamlets are located within Cardston County.
The following localities are located within Cardston County.
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In the 2021 Census of Population conducted by Statistics Canada, Cardston County had a population of 4,856 living in 1,143 of its 1,387 total private dwellings, a change of from its 2016 population of 4,481. With a land area of , it had a population density of in 2021.
In the 2016 Census of Population conducted by Statistics Canada, Cardston County had a population of 4,481 living in 1,043 of its 1,260 total private dwellings, a change from its 2011 population of 4,167. With a land area of , it had a population density of in 2016.