An Inherited IRA Created Income She Never Asked for, and a $6,936 Medicare Surcharge She Never Saw Coming

The Inheritance That Arrived as a Tax Bill

She is 66, retired, on Medicare, and living comfortably on Social Security plus modest withdrawals from her own savings. Then a parent passed away and left her a traditional IRA worth several hundred thousand dollars. Under the SECURE Act, most non-spouse heirs who inherited in 2020 or later must empty the account within 10 years. Worried about the deadline, she took a large lump distribution in 2024 to settle the matter quickly.

That single decision is now costing her $6,936 in extra Medicare premiums for 2026, on top of income tax she already paid. The money was never income she chose to earn, but the IRS and Medicare treat it exactly as if she had.

This scenario appears in retirement forums every week: someone inherits a parent’s IRA, worries about the 10-year clock, withdraws a large amount early, and only later learns that Medicare indexes premiums to income from two years back.

How a Two-Year Lookback Turned Into a $6,936 Surprise

Medicare’s Income-Related Monthly Adjustment Amount, or IRMAA, is the surcharge added to Part B and Part D premiums for higher-income beneficiaries. 2026 premiums are calculated using the modified adjusted gross income (MAGI) reported on the 2024 tax return. A one-time income spike in 2024 sets the bill two calendar years later, after the money is already spent or reinvested.

Inherited traditional IRA distributions are fully taxable as ordinary income and count toward MAGI. Stack a large distribution on top of Social Security, a pension, and ordinary investment income, and MAGI can jump from comfortably middle-class to the highest IRMAA tier in one tax year.

IRMAA begins once MAGI tops $109,000 for a single filer or $218,000 for a married couple filing jointly, and the top tier kicks in at $500,000 single or $750,000 joint. It works as a cliff. One dollar over a threshold moves a household into the next bracket for the entire year.

At the top tier in 2026, the numbers look like this:

• Standard Part B premium: $202.90 per month
• Part B IRMAA surcharge: $5,844 for the year
• Part D IRMAA surcharge: $1,092 for the year
• Total extra cost: $6,936

The Part B portion is pulled directly out of her Social Security check, shrinking the monthly deposit she budgets around. The Part D portion is billed separately by Medicare, which most people forget exists until the letter arrives.

Where Social Security Sits in the Picture

Social Security matters in two ways. First, it is the income stream that absorbs the surcharge. A retiree drawing roughly $2,400 a month will see her net check drop by hundreds of dollars once the Part B adjustment is applied. Second, Social Security benefits themselves count toward the income calculation that triggered the surcharge, so claiming and withdrawal decisions are linked.

The good news: IRMAA is recalculated every year. If 2025 income returns to normal, the 2027 premium should fall back to the standard amount. The surcharge is painful but usually a one-year event.

The harder news: simply inheriting money is not on the Social Security Administration’s (SSA’s) list of qualifying life-changing events for an SSA-44 appeal. Marriage, divorce, work stoppage, and the death of a spouse qualify. A windfall does not. The lever that works is spreading distributions across years to avoid triggering the surcharge in the first place.

What to Think Through Before the Next Distribution

If a 10-year deadline applies to an inherited traditional IRA, spreading withdrawals across the full window rather than front-loading them is usually the better path. Smaller distributions over eight or nine years often keep MAGI under the IRMAA cliffs entirely and allow coordination with lower-income years, such as before Social Security starts or before required minimum distributions (RMDs) on other accounts begin.

The mistake hardest to undo is the one made in a hurry. Once a distribution is taken and the tax year closes, the IRMAA consequence two years out is locked in. A short conversation with a tax preparer before December often saves more than a year of careful budgeting after the fact. Every inheritance situation has its own variables, so the right pace of withdrawals depends on the rest of the income mix, not a rule of thumb.