@Muse9876 wrote:
Can I just attach a copy of my Schedule D form from 2019 with a notation to add to my 2020 capital losses and attach to 1040X?
No, you can't expect the IRS to do the calculations for you. You have to file a proper Form 1040-X with an amended Schedule D attached, showing the correct capital loss carryover, as fanfare said.
Are you following the instructions at this link to amend your 2020 tax return?
How do I amend my 2020 return?
