Should form 8606 part 1 be filled out? I did a non-deductible IRA contrib then roth conv yet appears i'm being taxed on full contribution.

[mark-zukas]

My 1099-R has gross distribution and taxable amount the same ($8K), and taxable amount checkbox not determined. Yet I have form 1040 4b with that $8000 marked as taxable. I indicated in Turbotax it was 100 converted to a Roth but it didn't ask me how much was post-tax income.

[MindyB]

Yes. You need to enter the contribution to the non-deductible IRA separately from the conversion reported on the 1099-R.

Here's how to do this in TurboTax Online:

1. Navigate to Federal > Deductions & Credits > Retirement and Investments>  Traditional IRA and Roth IRA > Revisit
2. Continue through interview again, when you are asked Is This a Repayment of a Retirement Distribution? screen, select No.
3. On the Tell Us How Much You Contributed screen, enter $8,000 and select Continue.
4. On the Did You Change Your Mind? screen, select No, then answer the questions on the following screens.
5. When you reach the Choose Not to Deduct IRA Contributions screen:
   1. Select Yes, make part of my IRA contribution nondeductible.
   2. Enter $8,000.
   3. Select Continue.
      1. If your income was too high to deduct this, you won't need to follow step 5.  It will automatically be nondeductible.

Here are the full instructions to report a Backdoor Roth: How do I enter a backdoor Roth IRA conversion?