# Should I make a Roth conversion?

Estimates the 2026 tax on converting a traditional IRA or 401(k) to a Roth, and compares the Roth with keeping the traditional account and paying tax on withdrawal later, with the break-even future tax rate.

- Page: https://www.acalculator.org/finance/roth-conversion-calculator
- JSON spec: https://www.acalculator.org/finance/roth-conversion-calculator.json
- Version: 5205adfc0fa8

## Default answer

Example with the default inputs (Amount to convert $50,000.00, Other taxable income $80,000.00, Filing status Married filing jointly, State tax rate now 0%, Tax rate when you withdraw 22%, Years until you withdraw 20, Yearly return 6%, Pay the conversion tax from Savings outside, Tax on outside investment returns 15%): Converting $50,000.00 costs $6,000.00 in tax now; after 20 years, converting comes out ahead by $19,052.71.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| amount | Amount to convert | The pre-tax amount moved from a traditional IRA or 401(k) to a Roth this year. |
| income | Other taxable income | Your other taxable income this year before deductions. |
| status | Filing status | Your federal filing status. |
| state | State tax rate now | Your state income tax rate on the conversion (0 where there is none). |
| future | Tax rate when you withdraw | Your expected combined federal and state tax rate on traditional withdrawals in retirement. |
| years | Years until you withdraw | How many years the money grows before you take it out. |
| growth | Yearly return | The yearly return on the investments, the same in both accounts. |
| payFrom | Pay the conversion tax from | Savings outside the IRA (the whole amount goes into the Roth), or the IRA itself (less goes into the Roth). |
| sideTax | Tax on outside investment returns | If you do not convert, the tax money stays invested outside; the tax rate on its yearly returns. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| advantage | Gain from converting | After-tax value if you convert minus after-tax value if you keep the traditional account; below 0, keeping wins. |
| verdict | Result | Which choice comes out ahead after tax at the end, and by how much. |
| taxNow | Tax on the conversion now | Federal tax the conversion adds plus state tax. |
| federalTax | Federal tax on it | Your 2026 federal tax with the conversion minus without it. |
| effectiveRate | Tax rate on the conversion | The tax on the conversion divided by the amount converted. |
| marginalRate | Top federal bracket | The federal bracket of the last dollar converted. |
| rothValue | Roth at the end | The Roth after the years of growth, tax free. |
| keepValue | Keep: after tax at the end | The traditional account after the future tax, plus any outside money kept. |
| breakEvenRate | Break-even future tax rate | The tax rate on withdrawals at which converting and keeping come out the same; above it, converting wins. |

## Method

Tax now = 2026 federal tax with the conversion − without + state rate × amount; convert: Roth = (amount, or amount − tax if paid from the IRA) × (1 + r)ⁿ; keep: amount × (1 + r)ⁿ × (1 − future rate) + tax kept outside × (1 + r × (1 − outside tax))ⁿ.

## Assumptions

- Federal tax for tax year 2026 with the standard deduction and brackets; all other income is ordinary income.
- Both accounts earn the same steady return. Roth withdrawals are qualified (after 59½ and five years) and tax free.
- Paying the tax from the IRA before 59½ can add the 10% early withdrawal tax on that part; it is not included.
- A conversion raises this year’s income, which can raise Medicare premiums (IRMAA), make more Social Security taxable, and reduce credits; none of these are included.
- The future tax rate is your estimate; nobody knows future tax law.

## Worked examples

1. amount = $50,000.00, income = $80,000.00, status = mfj, state = 0%, future = 22%, years = 20, growth = 6%, payFrom = ira gives federalTax = $6,000.00, taxNow = $6,000.00, breakEvenRate = 12%, advantage = $16,035.68. Source: 2026 joint brackets (Rev. Proc. 2025-32) and Tax Table method.
2. amount = $100,000.00, income = $0.00, status = single, state = 5%, future = 24%, years = 10, growth = 0%, payFrom = outside, sideTax = 15% gives federalTax = $13,176.00, taxNow = $18,176.00, rothValue = $100,000.00, keepValue = $94,176.00, advantage = $5,824.00, breakEvenRate = 18.176%.
3. amount = $10,000.00, income = $0.00, status = mfj, state = 0%, future = 12%, years = 30, growth = 7%, payFrom = ira gives taxNow = $0.00, advantage = $9,134.71, breakEvenRate = 0%.

## FAQ

### How is a Roth conversion taxed?

The pre-tax amount you convert is ordinary income in the year of the conversion. It is added to your other income and taxed at your federal bracket, and usually by your state. There is no 10% early withdrawal tax on a conversion itself.

### When does a Roth conversion make sense?

When your tax rate now is lower than the rate you expect when you withdraw. The break-even future tax rate on this page is the withdrawal tax rate at which converting and keeping the traditional account come out the same; if you expect a higher rate, converting wins.

### Should I pay the tax from the IRA or from savings?

Paying from savings outside the IRA moves the whole amount into the Roth, which usually helps more. Paying from the IRA converts less, and before 59½ the part used for tax can owe the 10% early withdrawal tax.

### Can I undo a Roth conversion?

No. Since 2018 a conversion cannot be recharacterized back to a traditional IRA (IRS Publication 590-B).

### What else does a conversion change?

The extra income can raise Medicare premiums two years later (IRMAA), make more of your Social Security taxable, and reduce credits and deductions that phase out with income. This calculator does not include those.

## Sources

- Internal Revenue Service, Publication 590-B (2025), conversions and the recharacterization rule: https://www.irs.gov/publications/p590b
- Internal Revenue Service, Publication 590-A, Roth IRA conversions: https://www.irs.gov/publications/p590a
- Internal Revenue Service, Rev. Proc. 2025-32 (2026 brackets and standard deduction): https://www.irs.gov/irb/2025-45_IRB