How to avoid change of Cost Basis? In 2017 I created a rollover IRA from a 401k plan that also had a small after-tax (nondeductible) amount. Turbotax didn't create Form 8606 in 2017. Ideally, I would have preferred to take a total distribution of nondeductible amount in 2017 and just rolled over deductible amount. In 2019, I did a partial withdrawal thinking that it will be tax free withdrawal from nondeductible amount in my IRA. It seems that I should have created form 8606 in 2017. Also, this withdrawal, causes me to change my IRA cost basis. It's also very confusing as I have other IRA and Roth IRA accounts. This new basis will be with me as long as I have an IRA. I have two questions: 1) How can I cleanup this mess and bring cost basis to zero, 2020 onwards? 2) Why Turbotax didn't create Form 8606 in 2017 during my tax filing?
