You can still prepare and file (by mail) a 2013 return. You can purchase 2013 desktop software as a download from TurboTax at the link below.
https://turbotax.intuit.com/personal-taxes/past-years-products/
The 2013 return has to be printed and mailed. It cannot be efiled.
You can even file years prior to 2013, but if you are due a Federal refund, the statute of limitations to get the money is 3 years from the due date of the original return, or extended due date (if applicable.)
So a 2013 return which was due in April 2014, has until this year's filing deadline in April 2017 to get a refund. If an extension was timely filed in 2013, one would have until this year's filing deadline in October 2017.
