A Statistics Canada report has found that international migration remains the principal source of population growth in census metropolitan areas (CMAs), particularly in Western Canada. The study covers the years 2014/2015.

While immigration was the source of 60% of population growth in CMAs, its contribution was down from 2013/2014 (66%).

Statistics Canada estimates indicate that the seven CMAs with the highest relative rate of population growth were all located in Western Canada. Of these, Kelowna (+3.1%) and Abbotsford-Mission (+1.4%) are located in British Columbia; Calgary and Edmonton (both +2.4%) are in Alberta; Saskatoon (+2%) and Regina (+1.9%) are in Saskatchewan; and Winnipeg (+1.4%) is in Manitoba.

In contrast, the CMAs that posted population decreases were all located in Eastern or Central Canada. The population decreased in the CMAs of Saint John, NB (-0.4%), Greater Sudbury, ON (-0.3%), Saguenay, QC (-0.2%), Peterborough (-0.2%), ON, and Thunder Bay (-0.2%), ON.

Around 7 out of every 10 residents of Canada, or 25,164,126 people, reside in CMAs. Population aging is increasing outside CMAs, with non-CMA areas having a median population of 43.9 years, as opposed to 39.3 in CMAs. Canada's overall population is estimated to be 35,851,774.

Over the period 2005–2015, overall population growth in non-CMA areas was 4%. In contrast, CMAs saw an average population increase of 15% over this time. The CMAs with the most rapid population increases were Calgary (+32%) and Edmonton (+31%), while Toronto (+17%), Vancouver (+16%), Ottawa (+15%) and Montreal (+11%) also experienced population growth at or above the national average of 11%.

A CMA is an area consisting of one or more neighbouring municipalities situated around a core. A CMA must have a total population of at least 100,000, of which 50,000 or more live in the core. Canada currently has 33 CMAs; regions that are not CMAs are categorized as non-CMAs.

To view an interactive map of population change in Canada over the period 2011–2015, click here (source: data analyst William Davis).