Surviving Spouse IRA RMD Calculator

When your spouse dies and you roll their IRA or 401(k) into your own account, your required minimum distributions don’t start until you reach age 73 or 75 — but after years of tax-deferred growth, those RMDs can be large enough to push your Medicare IRMAA tier and increase taxes significantly. This calculator projects your annual RMDs through age 85, shows when they begin, and flags the $109,000 single-filer IRMAA cliff.

The RMD cliff most widows don’t see coming: A widow who rolls a $1.5M IRA into her own account at age 67 and earns 5%/year will have roughly $2.0M when RMDs begin at 73. Her first RMD: around $76,000/year. By age 80, shrinking distribution periods push the annual RMD past $100,000 — permanently triggering IRMAA Medicare surcharges of $974–$5,148/year even before Social Security income is added. Planning a Roth conversion strategy before RMDs begin is far cheaper than managing the cliff after it arrives.

The two IRA paths for surviving spouses — and how they affect RMDs

When your spouse’s IRA or 401(k) comes to you, the most important decision you face is how to hold the account. Your choice determines when RMDs begin and how much they are.

Path 1: Spousal rollover (roll into your own IRA)

You roll the inherited account into an IRA in your own name. The IRA becomes yours entirely. RMDs don’t start until you reach your own RMD age (73 or 75 depending on birth year). This is almost always the best choice for surviving spouses who are 59½ or older and don’t need immediate access to the funds — it maximizes tax-deferred growth and defers mandatory withdrawals as long as possible.

Path 2: Keep as an inherited IRA

You keep the account in your late spouse’s name as an inherited IRA and name yourself as the beneficiary. This is the better choice if you are under 59½, because the 10% early withdrawal penalty that normally applies to IRA distributions does not apply to inherited IRA accounts. Once you reach 59½, you can roll the inherited IRA into your own account at any time. Under the surviving spouse’s special rules (unlike non-spouse beneficiaries), you are not subject to the 10-year rule — you use your own life expectancy to calculate distributions.¹

Key difference from non-spouse beneficiaries: Non-spouse heirs who inherit an IRA must typically empty it within 10 years (and in many cases take annual distributions if the original owner had started RMDs). Surviving spouses have much more flexibility. You can roll the account into your own IRA and treat it as if you contributed to it yourself, with no 10-year deadline.

The IRMAA interaction: RMDs can raise your Medicare premiums

Medicare Part B premiums for 2026 start at $202.90/month — but once your Modified AGI as a single filer exceeds $109,000, surcharges begin. Every dollar of IRA withdrawal (including RMDs) flows directly into your MAGI. Social Security income and pension income add to that total.

2026 MAGI (single filer)	Part B premium	Annual cost vs. base
$0–$109,000	$202.90/mo	—
$109,001–$137,000	$284.10/mo	+$974/yr
$137,001–$164,000	$365.30/mo	+$1,949/yr
$164,001–$191,000	$446.50/mo	+$2,923/yr
$191,001–$500,000	$527.70/mo	+$3,898/yr
Over $500,000	$608.90/mo	+$4,872/yr

2026 IRMAA brackets per CMS. Your 2026 IRMAA surcharge is based on 2024 MAGI. If your spouse died in 2024 or 2025 and joint-return income was high, file Form SSA-44 to use your new, lower income instead. See the IRMAA appeal guide.

The QCD strategy: eliminate up to $111,000 in RMD taxes

Once you turn 70½, you can make a Qualified Charitable Distribution (QCD) directly from your IRA to a qualifying charity. The amount — up to $111,000 per year (2026 limit, indexed for inflation) — counts toward your RMD obligation but is excluded from your AGI entirely.² This has three compounding benefits for widows:

Satisfies your RMD without the distribution entering your taxable income
Keeps MAGI below the IRMAA cliff ($109,000 single filer, 2026)
Reduces the portion of Social Security that is taxable (single-filer provisional income thresholds are $25,000 and $34,000 — significantly lower than the married thresholds)

If your charitable intent already exists, a QCD is almost always more tax-efficient than taking the RMD, paying taxes, then donating the remainder for a deduction.

Reducing future RMDs with Roth conversions before age 73

Every dollar in a traditional IRA will generate a mandatory distribution at some point. Every dollar in a Roth IRA will not — Roth IRAs have no RMD requirement. Converting traditional IRA funds to Roth during the years between your spouse’s death and your RMD start age is one of the most powerful tools available to widows who have large inherited IRAs.

The ideal conversion window for most widows:

The year of death (filing MFJ for the last time): Married filing jointly brackets are roughly twice the width of single-filer brackets. Converting a large amount in this final joint year can lock in the lower rate permanently. See the Roth conversion guide for widows.
Years 2–N before RMDs start: Each year you convert reduces the IRA balance that will generate future mandatory distributions. Even converting $50,000–$75,000/year for several years can meaningfully lower age-80 and age-85 RMDs and the IRMAA exposure they create.

Example: A widow converts $60,000/year for 5 years before age-73 RMDs begin, reducing a $900,000 IRA to approximately $600,000 (net of growth). Her first RMD drops from ~$33,960 to ~$22,640. By age 80 that gap compounds — and $300,000 now sits in Roth, growing tax-free, with no RMDs ever required.

Related guides and tools

RMD Rules After Your Spouse Dies — the full guide to how RMD rules change when your spouse passes
Inherited IRA Rules for Surviving Spouses — spousal rollover vs. inherited IRA election: the decision flowchart
Roth Conversion Strategy for Widows — using the joint-year MFJ window before single-filer brackets apply
IRMAA Appeal Guide (Form SSA-44) — reduce Medicare surcharges caused by old joint-return income
Charitable Giving Strategies for Widows — the QCD strategy, donor-advised funds, and IRMAA management
Widow’s Income Gap Calculator — model your full monthly income, expenses, and savings runway
Widow’s Tax Penalty Calculator — side-by-side MFJ vs. single filer federal tax comparison

Get your RMD strategy modeled by a specialist

This calculator shows projected amounts. A fee-only advisor specializing in widows runs your full scenario — Roth conversion strategy, QCD sequencing, IRMAA tier management, and Social Security interaction — to minimize the lifetime tax cost of your IRA distributions.

Sources

Distribution periods from IRS Pub. 590-B Appendix B, Table III (Uniform Lifetime Table), T.D. 9930 effective 2022 and unchanged for 2026. IRMAA 2026 Part B brackets per CMS; based on 2024 MAGI. QCD $111,000 limit: 2026 inflation-indexed amount per IRS Notice 2025-82 (as cited by Kiplinger/Fidelity). All figures verified June 2026.