I'm using TurboTax premium. At the end of 2023 I had a traditional IRA with a cost basis of 0. At the beginning of 2024 I did a non-deductible contribution of $8000 to the traditional IRA. I then immediately did a conversion of the $8000 to a Roth IRA. This included $1 of interest so the total conversion was $8001. At this point my traditional IRA contained $0. Later in 2024 I did a rollover of a large amount of a 401K to the traditional IRA. The remaining part of the 401K was converted to a Roth 401K. I have received two 1099-R forms, one for the conversion, and one for the rollover. At the end of 2024 the traditional IRA contained the rollover amount plus interest earned. Both 1099-Rs were imported into TurboTax. The rollover 1099-R was processed correctly with the amount that was moved to the Roth 401K being taxable. However the 1099-R for the conversion (the $8001) is being almost fully taxed, where the tax should only be for $1. The problem is that TurboTax does not allow the specification of the tax basis of the IRA at the time of the conversion to be $0. Instead it is using the amount at the end of the 2024, which includes the 401K rollover amount (plus interest earned). Form 8086 supports this scenario (I verified this with a CPA), but there seems to be no way in TurboTax to support this scenario. Please indicate if there is a way in TurboTax to support this scenario, otherwise I will likely stop using TurboTax.
