I don't see my exact situation addressed in this thread either. I have never filed a Form 8606 because I never realized that I needed to. I have been doing my own taxes all my life (I'm 69 and retired) and I don't use tax preparation software, so I was just ignorant of the requirement.
I have done partial Roth conversions from traditional and rollover IRAs in several of the past years, but there were NEVER ANY non-deductible contributions in the IRAs that were being converted. I have treated all of the Roth conversions as fully taxable distributions from my IRAs, and as such I have always paid all of the taxes due on the amounts converted. If I were to file the required Forms 8606 for the several previous years in order to comply with the filing requirement, would I be likely to incur the $50 penalty per year for failure to file?
One additional complication: in 2018 I took a distribution from a Roth IRA rather than adding to it. I couldn't figure out where to report that distribution on my income tax forms, and so I just left it off, because I knew it was not taxable. I see now that it probably should have been reported on Form 8606 as well. Once again, if I belatedly file an 8606 for 2018 it will not change my tax liability.
I am not looking forward to incurring several $50 penalties for cleaning up my bookkeeping oversight. Please tell me that the IRS is likely to waive these penalties since I paid all the taxes I owed!
