You can either go to www.turbotax.ca and click on the orange sign in button, if your 2014 return is done, or you can click on this link, which will take you to the 2014 sign in.
https://ww1.2014.turbotaxonline.intuit.ca
If you have not yet started a 2014 return, you can still get the 2014 tax year here:
http://turbotax.intuit.ca/tax-software/prior-year-taxes.jsp
