Census boundaries can change from census to census.  When you download census data for GIS purposes, you must use the correct corresponding boundary file.

Boundary files for all levels of Statistics Canada levels of geography are available for free download on the Statistics Canada site:

1. Go to Statistics Canada's site at http://www.statcan.gc.ca/start-debut-eng.html.
2. Click on Browse by key resource and select Census program.
3. Scroll down and click on Geography.
4. Click on Boundary Files under Spatial information products.

Boundary Files, Reference Guide: http://www.statcan.gc.ca/pub/92-160-g/92-160-g2011002-eng.pdf