If a prior year IRA basis was in form 8606 and using Turbo Tax for the first time, the FAQs do not explain how to enter the prior year basis from form 8606 (2016) in 2017

[dmertz · Accepted solution]

Go to Deductions & Credits -> Retirement and Investments -> Traditional and Roth IRA Contributions and proceed through the pages until TurboTax asks if you made any nondeductible traditional IRA contributions.  Answer Yes, then enter your basis from years prior to 2017 (from line 14 of your 2016 Form 8606).