TurboTax selects Form 1040 or Form 1040-SR based on your age at the end of the year that you are filing for. For your 2020 tax return, if you (or your spouse if filing jointly) were born on Jan. 1, 1956 or earlier, TurboTax will print Form 1040-SR. If you (or both of you if filing jointly) were born Jan. 2, 1956 or later, TurboTax will print Form 1040.
