If worksheet 1-1 is required then the TurboTax 8606 form will have a * (asterisk) next to line 15 and the "Taxable IRA Distribution Smart Worksheet) will be used instead of the 8606 lines 6-15 which is the same as Pub 590B worksheet 1-1.
Pub 590B says:
Contribution and distribution in the same year. If you
received a distribution in 2019 from a traditional IRA and
you also made contributions to a traditional IRA for 2019
that may not be fully deductible because of the income
limits, you can use Worksheet 1-1 to figure how much of
your 2019 IRA distribution is tax free and how much is taxable.
Worksheet 1-1.
Use only if you made contributions to a traditional IRA for 2019 that may not be fully deductible and have to figure the
taxable part of your 2019 distributions to determine your modified AGI. See Limit if Covered by Employer Plan in
chapter 1 of Pub. 590-A
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
