You cannot use TurboTax Online to file for past years. TurboTax Online is only for the current tax year, which is now 2024. To file for earlier years you have to use the CD or download TurboTax software for each year that you need. You can purchase downloads at the following link.
Past Years' Products
Tax returns for past years cannot be e-filed. You will have to print your past-year tax returns, sign them, and file them by mail. Mail each year in a separate envelope.
TurboTax no longer supports years earlier than 2021.
