Retirement · 2026 tax year
Roth Conversion Tax Calculator
See how much extra federal tax a Roth conversion could add this year, which bracket it may land in, and how much room you may have left before the next one.
Estimated extra federal tax
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Compare conversion amounts
Based on the income you entered above.
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How it's calculated
Worked example
How this calculator works
It estimates your 2026 federal income tax twice, once without the conversion and once with it, and shows the difference. It uses the 2026 brackets and standard deduction from the IRS, the extra standard deduction for people 65 and older, the new $6,000 senior deduction (2025–2028) and its income phase-out, and the rules for how much of your Social Security is taxable.
What it leaves out
- State income tax (many states also tax conversions).
- Itemized deductions, tax credits, capital-gains rates, and the 3.8% net investment income tax.
- Medicare premium surcharges (IRMAA). We flag when you may be near the first threshold.
- After-tax (non-deductible) IRA money, which changes how much of a conversion is taxable (the "pro-rata rule").
Common questions
What is a Roth conversion?
Moving money from a traditional IRA or 401(k) into a Roth IRA. The amount you convert is generally added to your taxable income for the year, so you may owe tax now in exchange for possible tax-free withdrawals later.
When is the deadline?
A conversion counts for the calendar year it's completed, so a 2026 conversion generally needs to be done by December 31, 2026. There's no extension to April like there is for contributions.
Is there a 5-year rule?
Yes. Each conversion generally has its own 5-year clock. Withdrawing converted money before it's been 5 years, if you're under 59½, may trigger a 10% penalty.
Should I pay the tax from the conversion itself?
Many people pay it from other savings so more money stays in the Roth, and if you're under 59½, money withheld from the conversion may be penalized. It depends on your situation, so it's worth asking a tax professional.
For education only. This is an estimate, not tax, legal, or investment advice, and it isn't a recommendation to convert or not convert. Tax rules are complex and change; your actual tax may differ. Consider talking with a qualified tax professional before making a decision. Figures: IRS Rev. Proc. 2025-32 and the One Big Beautiful Bill Act, last updated for the 2026 tax year.