Why Some Retirees Pay $689.90 a Month for Medicare While Others Pay $202.90

Most people on Medicare pay the standard Part B premium each month and never give it a second thought. In 2026, that amount is $202.90, up $17.90 from the 2025 level of $185.00, and it rarely becomes a major focus in retirement planning until it suddenly needs to be.

What catches many retirees off guard is learning that a neighbor, sibling, or former coworker carrying the exact same Medicare coverage is paying more than triple that amount every single month.

The difference has nothing to do with health history or plan selection. It traces entirely to income, specifically, income from two years ago, collected through a surcharge called IRMAA. Most people have no idea what IRMAA is until a letter from Social Security arrives telling them they owe more.

What IRMAA Is and Why It Exists

IRMAA stands for Income-Related Monthly Adjustment Amount. It is the mechanism Medicare uses to charge higher premiums to beneficiaries above certain income thresholds. The surcharge is added on top of the standard $202.90 Part B premium and rises across five tiers based on modified adjusted gross income (MAGI), which is adjusted gross income plus any tax-exempt interest income added back in.

For 2026, IRMAA kicks in above $109,000 in MAGI for single filers and $218,000 for married couples filing jointly. At the lowest surcharge tier, the total monthly premium rises to $284.10. At the top tier, which applies to single filers above $500,000 and joint filers above $750,000, the total monthly premium reaches $689.90. That gap versus the standard rate comes to $487 a month, or roughly $5,844 per year. According to the Medicare Trustees Report, about 5.1 million beneficiaries paid Part B IRMAA surcharges in 2025, representing roughly 7% of all enrollees.

IRMAA applies to both Part B and Part D premiums. Part D surcharges range from $14.50 to $91.00 per month in 2026, added on top of whatever a beneficiary already pays for their prescription drug plan. That cost layer goes largely unmentioned in most retirement planning conversations, even though it compounds the total exposure for higher-income enrollees significantly.

The Five Tiers for 2026

The table below shows how Part B premiums escalate across all five IRMAA tiers for individual and joint filers in 2026.

There is also a separate and considerably harsher schedule for married beneficiaries who lived with their spouse at any point during the year but file separate tax returns. In that situation, the standard $202.90 premium applies only below $109,000 in MAGI. Cross that line by even a dollar, and the surcharge jumps immediately to $446.30 for a total of $649.20 per month. Above $391,000, it reaches $689.90. Filing separately while married is one of the fastest ways to trigger a disproportionate Medicare surcharge, because the brackets that apply to single filers are compressed into just three steps instead of six.

One additional detail worth flagging: the top bracket ($500,000 for single filers, $750,000 for joint filers) is frozen by statute through at least 2028. Because the lower tiers are adjusted for inflation each year while the ceiling stays fixed, more high-income retirees will drift into the top tier over time even if their incomes remain relatively stable.

The Two-Year Lookback That Catches Retirees Off Guard

Medicare does not use current-year income to set premiums. It uses income from two years prior, meaning 2026 premiums are based on what appeared on the 2024 tax return. That lag creates a painful situation for retirees who have already left the workforce and dramatically reduced their income, yet are still paying a high IRMAA surcharge because of what they earned before retiring.

The cliff effect makes all of this worse. IRMAA thresholds are hard cutoffs, not gradual phase-ins. Cross into another tier by a single dollar and it triggers the full higher premium for the entire year. A large Roth conversion, a capital gain from selling a rental property, or a one-time business distribution in the wrong tax year can push MAGI over a threshold and generate thousands of dollars in unexpected Medicare costs two years later. Retirees who received retroactive Social Security benefit increases in 2024 under the Social Security Fairness Act face a similar risk: those lump-sum payments counted toward 2024 MAGI, and for some beneficiaries the added income was enough to cross an IRMAA threshold for the first time.

How to Manage MAGI Before It Becomes a Problem

The two-year lookback is both a planning opportunity and a trap. Retirees and their financial advisors who monitor MAGI carefully in the years leading up to and during Medicare enrollment can avoid unnecessary surcharges. Qualified charitable distributions (QCDs) allow IRA owners aged 70 and a half or older to direct up to $111,000 per year directly to a charity from their IRA, satisfying required minimum distributions without the amount ever appearing in adjusted gross income. That limit rose from $108,000 in 2025 and is now indexed for inflation annually.

The QCD strategy became even more attractive following enactment of the One Big Beautiful Bill Act in 2025, which introduced a 0.5%-of-AGI floor on itemized charitable deductions starting in 2026, meaning the first 0.5% of AGI in donations generally produces no current-year deduction for itemizers. QCDs sidestep that floor entirely because the distribution bypasses AGI rather than flowing through as income first. The reduction in MAGI is dollar-for-dollar regardless of whether the taxpayer itemizes. Spreading Roth conversions over multiple years, rather than executing a single large conversion, similarly prevents MAGI from spiking across a tier boundary in one tax year. Timing capital gains across tax years can smooth the income curve that Medicare will eventually evaluate.

The Appeal Option Many Retirees Do Not Know Exists

A higher IRMAA bill is not necessarily final. Form SSA-44, available through Social Security, allows beneficiaries to appeal their surcharge when a qualifying life-changing event has reduced income since the year being evaluated. Retirement, divorce, the death of a spouse, and the loss of income-producing property all qualify.

Medicare will not automatically adjust premiums when income drops. The beneficiary must initiate the appeal, and many simply do not know the option exists until they have already paid the higher amount for months or longer. Filing promptly after a qualifying event is the only way to stop the overpayment from continuing.

One particularly painful scenario is what retirement planners sometimes call the widow or widower trap. When a spouse passes away, the survivor’s tax filing status switches from married filing jointly to single. At the exact same income level, single filers hit IRMAA brackets far sooner than joint filers. The result can be a significant premium increase even though nothing about the surviving spouse’s day-to-day spending or finances has changed. Filing Form SSA-44 promptly after such a life event is the most direct way to address that problem.

The gap between $202.90 and $689.90 per month is not arbitrary. It traces back to income from two years earlier, hard tier cutoffs with no phase-in, and a system that does not volunteer adjustments when circumstances change. Getting familiar with how IRMAA works well before Medicare enrollment, and revisiting it every year during the window that feeds the two-year lookback, is one of the more straightforward ways to protect retirement cash flow from a cost most people never see coming.

Editor’s note: This article has been updated to reflect the One Big Beautiful Bill Act’s 0.5%-of-AGI floor on itemized charitable deductions (effective 2026) and to note that retroactive Social Security Fairness Act payments received in 2024 may have pushed some beneficiaries across an IRMAA threshold for the first time in 2026.

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