Yes. You can still file your 2015 return.
https://turbotax.intuit.com/personal-taxes/past-years-products/
You can purchase a 2015 product from the link below, or from a reputable 3rd party. Just keep in mind that you cannot use the Turbo Tax website to prepare a prior year return. Our website only operates for the current filing year (2016).
Three-year window. You have three years to claim a refund. If you don’t claim your refund within three years, the money becomes property of the U.S. Treasury. For 2015 returns, the window closes on April 15, 2019. You must properly address, postmark and mail your return by that date. There is no penalty for filing a late return if you are due a refund.
