Taxable inherited IRA calculation error 2020 turbotax. I dont have an inherited IRA

[RPFO]

Suggest you update your copy on your computer that way it is available for next year's upload. One thing I believe folks do not realize is that the 8606 form also serves to recognize that your additional payments to IRA are recorded and credits given to your yearly submittals. It is not very apparent and it would have slipped by me if I did not ask a CPA some years ago. The CPA noted that the IRS does not give you lump-size credits - that the dollar amount is low compared to your investment and will take years to cover all amounts. 

[mainett]

Perhaps I'm late to the party. I do have an inherited IRA. Two weeks ago,  I entered my 1099-R into Step by Step, the fields for box 1 (Gross distributions) and box 2 (Taxable amount). When I printed out Form 1040, only the box 1 entry flowed into 1040 Line 4a. The Box 2 entry should have been on Line 4b, but was 0.

Two days ago, when I updated the software (for other reasons), the box for 1040, 4b had the correct entry. Seems like there are other problems afoot besides the ones described earlier.

[gattaca]

^^^ I've not tried to update any forms yet and remove my overrides.  As I mentioned in another thread, I'll make a copy of the file as a fall-back before undoing my overrides to make the numbers agree before TT has supposedly fixed it.  

^^^ There is a "manual form mode"  I've seen to add forms of your choosing.  I've never had to use it b/c the guided forms always got the forms right.  If there are any red "!", in front of a form, you cannot file it.   

^^^ WRT 8606 forms, my accountant said they should should be "retained indefinitely" to prove any yearly non-deductible contributions down the road. 

I'm so hoping this is fixed, otherwise we cannot eFile and must print everything and figure out how to correct the TT "faulty math..."    Stay safe, stay alive!  Peace.