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, this amount is $202.90, which is a reasonable enough number that it rarely becomes a major focus in retirement planning. 

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

The difference isn’t tied to health history or even which plan someone chooses. It all comes down to income, specifically, income from two years ago, better known as a surcharge called IRMAA. The tricky part? Most people have no idea what IRMAA is until a letter from Social Security arrives, letting them know they owe more. 

What IRMAA Is and Why It Exists

IRMAA stands for Income-Related Monthly Adjustment Amount, and 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, 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, a difference of $487 a month compared to the standard rate, or roughly $5,844 per year. 

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 harsher schedule for married beneficiaries who lived with their spouse at any point during the year but file separate tax returns. In that case, the standard $202.90 premium applies only below the $109,000 in MAGI. 

Above that number, the surcharge jumps immediately to $446.30 for a total of $649.20, and above $391,000, it reaches $689.90. Filing separately while married is one of the fastest ways to trigger a disproportionate Medicare surcharge. 

The Two-Year Lookback That Catches Retirees Off Guard

This is where many people get blindsided, as Medicare does not use your current-year income to set your premium. It uses income from two years prior, meaning 2026 premiums are based on what appeared on your 2024 tax return. This two-year lookback creates a situation where a retiree who has already left the workforce and dramatically reduced their income can still be stuck paying a high IRMAA surcharge because of what they earned before retiring. 

The cliff effect makes all of this worse, as IRMAA thresholds are not gradual, as some people might believe. Instead, they are hard cutoffs, and if you cross into another tier, even by as little as a single dollar, it triggers the full higher premium for the entire year. A large Roth conversion, a capital gain from selling a rental property, or even a one-time business distribution in the wrong year can make sure that your MAGI is pushed over a certain threshold. If this is the case, it results in thousands of dollars in unexpected Medicare costs two years later. 

How to Manage MAGI Before It Becomes a Problem

The big takeaway here is that the two-year lookback is both a planning opportunity and a trap. If a retiree and their financial advisors can carefully watch their MAGI in the years leading up to and during Medicare enrollment to avoid unnecessary surcharges. Qualified charitable distributions allow IRA owners aged 70½ or older to direct up to $108,000 per year to a charity from their IRA, satisfying required minimum distributions without the amount ever appearing in AGI. 

Spreading Roth conversions over multiple years, rather than doing a single large conversion, keeps MAGI from spiking in a single tax year and crossing a threshold. Similarly, 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

If your income has taken a big hit since the years the IRS is looking at your Medicare premiums, don’t assume you’re just stuck paying that higher amount. The good news is that there is a way to actually fight it, it’s called Form SSA-44, and you can get it through Social Security. It lets you appeal your IRMAA surcharge if you’ve had a major life change, like retiring, getting divorced, losing your spouse, or selling property that used to generate income. 

But, there is a catch, as Medicare won’t automatically adjust your premiums when your income goes down. Instead, you have to review yourself, and honestly, a lot of retirees have no idea this option even exists. 

One especially painful scenario is what we 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 those IRMAA surcharge brackets way sooner. In other words, you could be looking at a massive premium hike, even though nothing about your day-to-day spending or lifestyle has changed. 

There’s a reason that the monthly number can jump from $202.90 all the way up to $689.90, and it’s not random. It all ties back to income from two years ago, those rigid cutoffs, and, more often than not, a simple lack of awareness that this was even on the horizon. The real takeaway? Understanding how IRMAA works before you enroll in Medicare, and especially in the years leading up to it, is one of the smartest, most low-risk moves you can make to protect your monthly cash flow.