Search this forum, google, reddit, etc - there are so many posts where Turbotax messed up AMT carryovers losses. So much so, in 2023, there is an entire "TY21 -> TY22 conversion AMT capital loss carryover adjustment smart worksheet" form for users to fill out.
Unfortunately, I filled that one out incorrectly, so all of my AMTs are incorrect going back to 2020. I can manually fix it now in 2024 with the new "You probably don't, but we have to ask—do you have different carryover amounts for AMT?" feature and all should be good. Do I still need to amend all the old returns for Turbotax's incorrect AMT calculation? It's been incorrect for the past 3 filings
To be clear, it's ONLY the AMT that's incorrect. There will be net 0 change in calculation (I don't have enough newer capital gain/loss to warrant a change). Obviously if this error would change the refund or due amount should amend, but it doesn't. In other words, if hypothetically I amend and fix the issue or hypothetically this issue didn't happen at all, it would net out to 0 change (no more due, no more refund).
