Didn't have 8606 for 2 years with nondeductible IRA. What to do now before I can do a backdoor Roth IRA?

[bondtradercu]

So, I am planning to do a backdoor Roth IRA conversion this year and only recently realized I should have been keeping track of my nondeductible traditional IRA contribution.

I went back to my previous Turbotax returns and only see 8606 being generated for 1 year only - not sure why it wasn't generated for couple years when my MAGI is higher than the income limit for deductible traditional IRA (doesn't Turbotax track this automatically and generate a 8606 on your behalf? - I assume that was how I got 8660 for one year). However, now as of today, there is only the basis from that 1 year with the 8606 filed, and missing other basis for couple more years. 

What are my options now? 

- Option 1: Do I have to file 8606 separately for each year with nondeductible contribution? starting with the oldest year first going to the most recent one? Only then can I do a backdoor conversion? 

- Option 2: Can I just amen the nondeductible basis on this year 2022 return and put in the explanation in the box Turboxtax has to explain why there is a discrepancy? 

- Option 3: Or do I just amend the latest 2021 tax return? 

Would love to hear all options and best way to do this. 

I plan to rollover all my deductible 401k contribution (rolled over to this tIRA) back to my employer 401k + all pre-tax earnings of my nondeductible contribution first so that the only thing left in my tIRA before conversion is just the nondeductible basis. 

[DanaB27]

You can file Form 8606 by itself if it doesn’t change the rest of the tax return. You will have to download for each year the Form 8606. You can find the prior year's Form 8606 on the IRS website.

Technically you can be fined $50 for failing to file the form on time, but the penalty can be waived if you have reasonable cause. Please see Relief for Reasonable Cause for additional information.