Each tax year must be entered separately on a tax return for the year being reported.
Using TurboTax you can complete and file prior year tax returns, 2018 thru 2016, by purchasing and downloading one of the desktop editions for each tax year required from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/
Any of the desktop editions can be used to report your self-employment income and expenses. However, the Home & Business edition is recommended.
A prior year tax return can only be printed and mailed, it cannot be e-filed. Use a separate envelope for each tax year being mailed.
For tax year 2019 you can use either the TurboTax online edition or the desktop CD/Download editions. The desktop editions are recommended.
TurboTax 2019 desktop CD/Download editions - https://turbotax.intuit.com/personal-taxes/cd-download/
A 2019 tax return can be e-filed up through October 15, 2020. After that date the 2019 tax return can only be printed and mailed.
