In the third quarter of 2012, all western provinces had rate of population growth similar to or above the national average. Among provinces, Alberta (+0.9%) and Saskatchewan (+0.6%) posted the largest population increase.
Alberta posted a population growth of 33,100 (+0.9%) in the third quarter of 2012 to 3,906,800 as of October 1, 2012. Population increase had not been this high for any quarter, with the exception of the third quarter of 1980. This growth was mainly the result of net interprovincial migration (+13,900), with net gain with Ontario (+5,900) and British Columbia (+4,000). (Source)