Inherited IRA Calculator — Methodology

How This Calculator Works

This calculator models distribution plans for an inherited IRA under the SECURE Act 10-year rule, and for eligible designated beneficiaries and spouses who take life-expectancy distributions. It compares four plans (equal, front-loaded, back-loaded and bracket-filling) and shows the federal income tax each one costs. When a minimum withdrawal is due every year, every plan is lifted to at least that minimum.

Inputs and Assumptions

• Inherited IRA balance: the balance at the date of death, grown to the current year at your expected return (assuming nothing has been withdrawn yet).
• Beneficiary type: non-spouse designated beneficiary (10-year rule), eligible designated beneficiary (life-expectancy “stretch”, shown as 20-year plans) or spouse keeping the account as inherited (30-year plans). On the last two, a minimum is due every year and every plan takes at least that.
• Account type: traditional (distributions taxed as ordinary income) or Roth (tax-free, assuming the 5-year rule is met).
• Year the owner died, and the owner's year of birth: these set the deadline and decide whether a minimum is due every year. The birth month is asked only for 1949 births, and the month of death only when the owner died in their required-beginning-date year.
• Your age, other income and filing status: used for the required minimum and for 2026 federal brackets and the standard deduction.
• Expected annual return: growth on the remaining balance.

Formula

// 10-year rule: empty by 31 December of the year that includes
// the 10th anniversary of death (26 CFR 1.401(a)(9)-5(e)(2))
deadline = yearOfDeath + 10
yearsLeft = deadline - currentYear + 1     // this year and the deadline year count

// Annual minimum (26 CFR 1.401(a)(9)-5(d)(1)), traditional IRAs only,
// when the owner died on or after their required beginning date (RBD:
// 1 April of the year after they reached 70½, 72 or 73), from 2025:
divisor(Y) = SingleLifeTable(your age in the year after death)
             - (Y - (yearOfDeath + 1))
minimum(Y) = balance at the end of Y-1 / divisor(Y)
// A Roth IRA is treated as if the owner died before the RBD:
// no annual minimum (26 CFR 1.408A-6, A-14(b))

// Eligible designated beneficiary (26 CFR 1.401(a)(9)-5(d)(3)(iii)):
divisor(Y) = SingleLifeTable(your age in the year after death)
             - (Y - (yearOfDeath + 1))         // never looked up again
// Spouse keeping it as inherited ((d)(3)(iv)):
divisor(Y) = SingleLifeTable(your age in Y)    // looked up again each year
// Owner died on or after the RBD ((d)(1)(ii)): the greater of that and
// SingleLifeTable(owner's age in year of death) - (Y - yearOfDeath)
// A spouse may wait until the year the owner would have reached RMD
// age when the owner died before the RBD (1.401(a)(9)-3(d)).
minimum(Y) = balance at the end of Y-1 / divisor(Y)   // all of it once divisor <= 1

// Each plan, each year before the deadline year:
withdrawal = max(plan amount, minimum)
// Deadline year: withdraw everything left
// Recommended pace = max(this year's minimum, balance / years left)

// Tax: 2026 federal brackets after the standard deduction,
// on your other income plus the withdrawal (incremental)

// 25% excise tax on a missed minimum (IRC 4974(a)); 10% if
// corrected within the correction window (4974(e))

Data Sources

• Final RMD regulations, T.D. 10001 (July 2024): 26 CFR 1.401(a)(9)-5(d) and (e), the annual minimum after the RBD, the life-expectancy minimum for eligible beneficiaries and spouses, and the 10-year deadline; 1.401(a)(9)-3(d), a spouse's permitted delay. They apply to RMDs for calendar years from 2025.
• Single Life Table, 26 CFR 1.401(a)(9)-9(b) (Table I in IRS Publication 590-B), the divisor for beneficiaries.
• 26 CFR 1.408A-6, A-14: inherited Roth IRAs are treated as if the owner died before the RBD.
• IRS Notices 2022-53, 2023-54 and 2024-35: no excise tax on a 10-year beneficiary's missed annual minimums for 2021 to 2024. They waived the penalty for those years; they did not remove the minimums, and they never covered an eligible beneficiary's or a spouse's life-expectancy minimum.
• IRC Section 4974: 25% excise tax on a missed required distribution (reduced from 50% by SECURE 2.0), 10% if corrected in time, and a waiver for reasonable error.
• IRS Publication 590-B: Distributions from Individual Retirement Arrangements.

Limitations

• Assumes nothing has been withdrawn since the owner died. If a minimum was due for an earlier year (2025 onward) and was not taken, the page says so but does not add it to the plan.
• The owner's own required minimum for the year they died is not modelled.
• Eligible designated beneficiaries and spouses are shown as 20- and 30-year plans that never take less than the yearly life-expectancy minimum. Not checked: a minor child's deadline (31 December of the year of their 31st birthday), the 10-year limit after an eligible beneficiary's own death, and the spouse's option to be treated as the owner.
• Without the owner's year of birth, the eligible beneficiary's or spouse's minimum uses their own life expectancy only and starts the year after death. That is the side that asks for more.
• Plans are compared on federal income tax only. They withdraw different totals because of growth, so a plan with less tax is not always the better plan.
• Does not model state income taxes, IRMAA, the Net Investment Income Tax or AMT.

Last Updated

April 2026 — Updated to reflect IRS Notice 2024-35 transition rules.

4 October 2026 — Adds the annual minimum that applies when the owner died on or after their required beginning date (the page had said there was none, and the plans could skip it). Counts the deadline year as a year to withdraw in (the schedule had ended a year early). Uses the Single Life Table in the current regulation.

14 October 2026 — Eligible designated beneficiaries and spouses now carry their yearly life-expectancy minimum. Before, these paths had none, and the recommended pace could be well below what the law requires. The recommended pace is never below this year's minimum on any path.