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Traditional IRA Deduction Phase-Out Calculator

Check how much of your Traditional IRA contribution is tax-deductible if you're covered by a workplace retirement plan.

Result

Deductible Amount
$2,800.00
Deductible Percentage
40%

Assumes you're covered by a workplace retirement plan (like a 401k) - if neither you nor a spouse is covered by a workplace plan, your full Traditional IRA contribution is deductible regardless of income. Uses 2025 phase-out ranges.

About the IRA Deduction Phaseout

The Traditional IRA Deduction Phase-Out Calculator figures out how much of a given year's Traditional IRA contribution can actually be written off against taxable income once the contributor or a spouse is covered by a workplace retirement plan. Deductibility for covered filers is not all-or-nothing; it shrinks gradually as modified adjusted gross income (MAGI) rises through an IRS-defined band. Anyone who contributes to a Traditional IRA while also participating in a 401(k) or similar plan can use this to see the real deductible dollar amount rather than assuming the full contribution qualifies.

How It Works

Enter filing status, modified AGI, and the dollar amount contributed to a Traditional IRA. The calculator applies the 2025 phase-out range for workplace-plan participants (79,000 dollars to 89,000 dollars for single filers, 126,000 dollars to 146,000 dollars for those married filing jointly) and works out what share of that range the MAGI has already used up. Below the range the full contribution deducts, above it none does, and in between the deductible share slides down in a straight line as income climbs.

deductiblePercent = 1 when MAGI is at or below phaseoutStart; deductiblePercent = 0 when MAGI is at or above phaseoutEnd; otherwise deductiblePercent = 1 - (MAGI - phaseoutStart) / (phaseoutEnd - phaseoutStart). deductibleAmount = contribution x deductiblePercent.

Formula & Methodology

For a MAGI that lands inside the phase-out band, first find how far into the band it sits by subtracting phaseoutStart from MAGI. Divide that by the total width of the band (phaseoutEnd minus phaseoutStart) to get the fraction of the deduction that has been phased out, then subtract that fraction from 1 to get the remaining deductible percentage. Multiply the contribution by that percentage to get the deductible dollar amount; the rest of the contribution can still go into the account but is treated as a nondeductible, after-tax contribution.

Examples

Single filer mid-phaseout

With MAGI of 85,000 dollars, single filing status, and a 7,000 dollar contribution, MAGI sits 6,000 dollars into the 10,000 dollar-wide phase-out band (79,000 to 89,000), leaving 40% deductible (2,800 dollars) and 60% nondeductible (4,200 dollars of basis).

Married couple above the range

A married couple with MAGI of 150,000 dollars contributing 8,000 dollars has MAGI already past the 146,000 dollar phase-out ceiling, so the deductible percentage is 0 and the entire 8,000 dollar contribution becomes nondeductible, reportable on Form 8606.

Advantages

  • Turns an IRS phase-out formula that is easy to misapply by hand into an exact deductible dollar figure and percentage for any MAGI and contribution combination.
  • Handles filing statuses correctly, since the married phase-out band is both higher and wider than the single band, not simply double it.
  • Flags whether a contribution is fully, partially, or not at all deductible before the return is filed, which affects whether Form 8606 needs to be attached.

Common Mistakes

  • Assuming the full IRA contribution limit is always deductible without checking whether the filer or a spouse has workplace plan coverage that tax year.
  • Using gross income or taxable income instead of modified AGI, which adds back certain deductions and can shift a filer further into or through the phase-out range.
  • Forgetting that a spouse who is not personally covered by a plan but is married to someone who is faces a different, higher phase-out range than this simplified version applies.

Edge Cases to Watch For

  • The phase-out only applies when the filer or a spouse is covered by an employer retirement plan; if neither is covered, the deduction is not limited by income at all and this phase-out band would not apply to that situation.
  • At MAGI exactly equal to phaseoutStart the deductible percentage is still 1 (full deduction), and at MAGI exactly equal to phaseoutEnd it drops all the way to 0 rather than tapering to a small positive number.
  • The thresholds used are 2025 figures; the IRS adjusts both the single and married phase-out ranges for inflation most years, so other tax years need different bounds.
  • A nondeductible portion is not simply lost. It still counts toward the annual IRA contribution limit and must be tracked as basis on Form 8606 to avoid being taxed again at withdrawal.

Common Use Cases

  • Dual-income households where one or both spouses participate in a 401(k) and want to know their real IRA deduction before contributing.
  • Tax preparers checking a client's Traditional IRA deduction quickly during a return review.
  • Anyone deciding between a Traditional and Roth IRA contribution who needs to know how much of the Traditional deduction they would actually get.
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

What happens to a non-deductible portion of an IRA contribution?

You can still make the contribution up to the annual limit even if it's not deductible, but the non-deductible portion becomes "basis" in your IRA that you report on Form 8606, meaning that portion won't be taxed again when withdrawn in retirement (only the growth and any deductible contributions will be) - keeping accurate Form 8606 records over the years is important to avoid double taxation later.

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Conclusion

Because the deduction phases out gradually rather than dropping off a cliff, the exact percentage depends on precisely where MAGI falls within the range. This calculator applies the 2025 thresholds directly to a given filing status, MAGI, and contribution amount so the deductible portion does not have to be estimated by hand.

References