Roth Conversions | Timing, Cost, and State Tax

Updated July 31, 2026. Quick answer: a Roth conversion is a decision about which year to pay tax, and almost every mistake comes from looking at one year in isolation. The window that matters most opens when earned income stops and closes when required distributions begin – inside it you may be in the lowest bracket you will ever see again. Against that sit the costs a conversion triggers in the same year: it can raise your Medicare premiums two years later, increase the share of Social Security that is taxable, and start its own five-year clock. And whether your state taxes the conversion at all is a separate question with fifty-one different answers, which is what the state pages below are for. Work out the decision first, then check your state, then check what the conversion costs elsewhere in your return.

Roth Conversions: When to Convert, What It Costs, and Which State Taxes It

Does your state tax a Roth conversion?

Deciding whether and when to convert

What a conversion sets off elsewhere

529-to-Roth rollovers

Other conversion questions

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