I run a Roth conversion calculator for several different scenarios. It takes all taxes in consideration and IRMAA (health care premiums). There are extra taxes once going over certain income limits, so it is important to take all into consideration when running multiple scenarios per family.
One very common thing is it almost always recommends to convert a lot in the first 2-6 years. I have seen it tell me that converting well into the 37% tax bracket saved the most taxes in the long run due to reduction in other taxes like IRMAA and NIIT.
At 80, it isn't as pressing to convert all, but if they live to 95-100, then it may. Also, if one of your parent passes soon and the other lives long, you are likely to be better off converting a lot soon.
I always pose it as do you want to give some money to the IRS or to your heirs or charity?
Maxifi is the one that is the best for analyzing but you would need some info to run it. Tax return and financial statements will do it.
Pretty sure you said most of this was in an IRA.
Keep in mind that this coming to you likely means more to the IRS than them. Also, it could create a huge tax problem for you because your personal IRAs may get too large due to not using them for those 10+ yrs.
If I am you, it would be hard to bring any of this up. I do seem to find most parents will consider listening if phrased like "I was watching a show/speech/podcast about large tax problems with IRAs and how to avoid a large amount of those taxes by proper tax planning. It was saying that most give more to the IRS than they had to and that money could have stayed with the family or gone to the charity. "
Too lazy to go back and check for comprehension, so feel free to PM me.
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