If your income sat between $137,001 and $171,000 the year before you left your job, you could be staring at a Medicare Part B bill of $405.80 a month in 2026, more than double what most people pay, even though you haven't earned anything close to that since you retired.
Medicare calculates your premium from a tax return that's already two years old by the time it takes effect, so the bill you're looking at often reflects the job you left, not the retirement you're actually living. Nobody warns you about this before you file for Medicare, and by the time the letter shows up, it can look like a billing mistake even though it isn't.
There's a specific form built to fix exactly this gap, and it can bring your premium back down to where it belongs within a few months.
Why your premium is still based on the job you don't have anymore
Medicare doesn't ask what you're earning this year. It looks at the tax return you filed roughly two years earlier and sets your premium from that. For 2026 coverage, Social Security is working from your 2024 tax return, whatever that return says, even if you retired the following month.
The lag exists because the IRS needs time to finalize your return and pass the data along to Social Security. By the time it's actually used to calculate your premium, you're often a full year or two removed from the income it describes. If your last full year of work pushed you over $109,000 as an individual filer or $218,000 filing jointly, Medicare treats you as a high earner for the following year too, regardless of what you're actually living on now.
This isn't unique to retirement. It happens to anyone whose income drops sharply, whether that's a layoff, a divorce, or the death of a spouse. Medicare just hasn't caught up yet.
What the 2026 premium brackets actually cost
The standard Medicare Part B premium for 2026 is $202.90 a month, up from $185.00 in 2025. That's what most people pay. Above certain income levels, Social Security adds a surcharge on top of the base premium called the income-related monthly adjustment amount, or IRMAA, and it climbs in five steps depending on how far over the threshold you are.
Roughly 8% of people with Medicare Part B pay one of these surcharges, on a sliding scale tied to the tax return you filed for 2024. Individual filers who reported $109,000 or less, or joint filers at $218,000 or less, stay at the standard $202.90. Above that, the premium steps up to $284.10 for individual income up to $137,000 (or $274,000 joint), then $405.80 up to $171,000 (or $342,000 joint), then $527.50 up to $205,000 (or $410,000 joint), then $649.20 up to just under $500,000 (or $750,000 joint). Anyone above that tops out at $689.90 a month.
Part D drug coverage carries its own surcharge on the same income scale, ranging from $14.50 to $91.00 a month on top of whatever your plan already charges. If you and a spouse are both on Medicare and both land in the same bracket, both of you pay the surcharge separately.
The two-year gap that catches new retirees off guard
Say your last full year of work, 2024, brought in $150,000. That lands you in the third bracket, so your 2026 Part B premium comes out to $405.80 a month instead of the standard $202.90. If you retired in early 2025 and your income for this year has dropped to $60,000, Medicare hasn't been told that. Social Security is still working off the 2024 return, so the higher bill keeps showing up until someone corrects it.
That gap adds up fast. Paying the higher rate instead of the standard premium costs an extra $2,434.80 a year for one person, and double that if a spouse is on Medicare and in the same bracket. Stretch that across the year or two it would otherwise take for your real income to work its way through the lookback, and it's real money sitting on the table for no reason other than paperwork.
The same gap shows up for reasons that have nothing to do with retirement. A spouse who dies leaves the survivor filing as single the following year, which can push them into a higher bracket even though household income just dropped. Someone who sold a rental property or cashed out a pension in their final working year can get stuck with an inflated premium long after that one-time income is gone. In every one of these cases, the bill on file reflects a version of your finances that no longer exists.
The form built for this exact situation
The fix is Form SSA-44, officially called Medicare Income-Related Monthly Adjustment Amount, Life-Changing Event. It asks Social Security to recalculate your premium using your current, lower income instead of the two-year-old return on file, on the basis that a specific, documented event caused the drop.
You can't file this ahead of time. You need to have already received an IRMAA determination letter stating you owe the higher premium, and you'll need documentation that backs up both the event and your new income, such as a retirement letter from your employer, a pension statement, or a written estimate of what you expect to earn this year.
Filing this form isn't the same as disputing your bill or arguing that Medicare made an error. Nothing about the original calculation was wrong. You're simply giving Social Security newer, more accurate information than the tax return they were required to use, and asking them to base your premium on that instead. Once approved, the adjustment covers both your Part B premium and any Part D surcharge, since both are calculated off the same income figure.
What actually qualifies, and what doesn't
Social Security spells out a specific, closed list of life-changing events that qualify: marriage, divorce, or the death of a spouse; you or your spouse stopping work or cutting back your hours; losing income-producing property in a disaster or similar event beyond your control; the shutdown or reorganization of an employer's pension plan; or a settlement tied to an employer's bankruptcy or closure. Retirement falls under stopping work. Dropping to part-time falls under reduced hours.
What doesn't count matters just as much. A bad year in the stock market doesn't qualify, and neither does a Roth conversion that temporarily spiked your income, even though both can change what shows up on your tax return. Social Security is looking for a specific triggering event, not a general shift in your finances, and the drop has to be big enough to actually move you into a lower bracket. If your income falls from $135,000 to $130,000, you're still in the same tier, and there's nothing for Social Security to adjust.
How to actually file, and what to expect
Once you have your IRMAA letter in hand, download and complete the form, choose which life-changing event applies, and note the date it happened. You'll estimate your income for the year the event affected, attach your supporting documents, and submit everything by mail, fax, or in person at a local Social Security office. You can also call Social Security at 1-800-772-1213 and start the process over the phone.
If you're married and both of you are on Medicare, each person files a separate SSA-44, even when the same life-changing event applies to both. You'll each get your own IRMAA determination letter, and each form needs its own supporting documents attached, so keep copies of everything before you send the originals in.
Processing generally takes a matter of weeks. If your request is approved, the lower premium applies going forward, and any amount you overpaid while the paperwork was pending is often refunded, though exactly how far back that refund reaches can vary case by case, so it's worth confirming the details directly with Social Security when you file. If your request is denied, you have the right to ask for a formal reconsideration.
Your Medicare premium should reflect the retirement you're actually living, not the paycheck you left behind. Filing the right paperwork is usually the only thing standing between you and the number that fits.
