The Form 1040 and Form 1040SR are identical except that 1040SR has bigger print. The lines are exactly the same; the calculations are done in exactly the same way. The software uses the date of birth you entered in My Info to select which form to put your return on. If you were 65 or older at the end of 2020, your tax return is on Form 1040SR.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
