Only the 2020 tax return is available to be completed and filed for free if you are eligible.
IRS website for free tax preparation software vendors - https://www.irs.gov/filing/free-file-do-your-federal-taxes-for-free
TurboTax does not support tax year 2016
Prior year tax returns using TurboTax, 2017 thru 2019, you would need to purchase one of the desktop editions for each tax year required from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
Prior year tax returns can only be printed and mailed, they cannot be e-filed using the TurboTax personal editions.
