Your basis on December 31, 2020, should be $12,000 from line 14 of your 2020 Form 8606. A contribution made in 2021 for 2020 is deemed to have been made on the last day of 2020.
@hdaniel1
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"
