The Futurez blog

Conversion advice is written as though the federal bracket is the whole bill. For most people your residing state matters.
Read enough about Roth conversions and you’ll notice something missing. Thread after thread works through bracket-filling, the timing of required minimum distributions, and whether to pay the tax from the conversion or from savings, and never mentions that a second government is also sending a bill.
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How your two-years-ago tax filing affects Medicare
It's a cliff, not a slope, and the delay is what makes it easy to walk off. Here's how the lookback works and what it does to a Roth conversion plan.

How much should you convert to a Roth this year?
The usual answer is fill up your tax bracket. That's a good start and a bad stopping point. Here's what else moves when you convert.