The amount of farmland in Canada serves as the basis for debate on a host of public policy issues ranging from food security to sustainability to competiveness. Despite the interest and the basis for policies such as land use controls, there is little documentation on total farmland area and composition in Canada. This report documents the changes in the total amount of farmland in Canada using data from the Census of Agriculture. The national and provincial trends in the composition of farmland from 1921 to 2016 are described with additional focus at the county level for Ontario. There are approximately 160 million acres of farmland in Canada. While there have generally not been significant changes in the amount of farmland between census periods, there were drops of around 4% in the 1981 and 2011 census. Most of this farmland is located in Saskatchewan (40%) and Alberta (31%), while the total amount in Ontario has fallen by 50% since 1941 and represents 8% of the Canadian total. Approximately half of Canada’s total farmland is used to grow crops. The amount of cropland has increased by 28% over the past 40 years with much of the growth occurring from 1976 to 2001. Seeded pasture, which makes up less than 10% of total farmland, has also increased over time with much of the increase occurring in the Prairies. While cropland and seeded pasture generally rose over time, the small decline in national farmland was due to the 92% drop in the area allocated to summerfallow since 1976. The total loss of 3.1 million acres of farmland in Ontario since 1976 is due largely to the reduction in non-cropland as the area planted to crop rose by 4% in total from 1976 to 2016. These changes in total farmland and its mix are evident for all regions although the mix varies significantly. Counties in the southwestern portion of the province have over 75% of their total farmland allocated to growing crops whereas this is approximately 50% in the rest of the province. This percentage, although smaller than in the southwestern region, has also increased over time due to the drop in pasture, fallow, and woodlot/wetland area.