Medicare Part D

IRMAA thresholds that lift Medicare costs in Mount Pleasant

MOUNT PLEASANT, Mich. — As the Medicare Annual Enrollment Period runs through Dec. 7, thousands of Michiganders are reviewing their 2027 coverage. But one detail often gets missed until a bill arrives: your income two years ago can raise what you pay for Medicare Part B and Part D next year.

The income question catching more Medicare enrollees off guard

The surcharge is called IRMAA — the Income-Related Monthly Adjustment Amount. It isn't a penalty, and it isn't tied to any specific plan you pick. It's a Medicare-wide rule that adds to your monthly premium if your income crosses certain lines. Here's how it works for 2027, who it affects, and what to do if your situation has changed.

What IRMAA is, in plain English

Most people pay the standard Part B premium and only their plan's Part D premium. But if your income is above a set threshold, Medicare adds an extra monthly amount on top — for both Part B and Part D.

A few key points to keep in mind:

• Medicare uses your tax return from two years ago. For 2027 premiums, that generally means your 2025 IRS return.
• The surcharge applies to Part B and Part D separately. If you owe IRMAA, you'll see it on both.
• Social Security handles the notification. You'll get a letter explaining the decision and how to appeal.
• It's recalculated every year. If your income drops, your surcharge can drop too.

The 2027 income thresholds

For 2026, IRMAA starts above $109,000 in income for a single filer (and above $218,000 for a married couple filing jointly). Below those numbers, you pay the standard Part B premium and just your plan's Part D premium — no surcharge.

Above the first threshold, the surcharge steps up through several income tiers. The higher your income, the higher the added amount for both Part B and Part D. Medicare updates the exact dollar figures for each tier each fall; the current chart is posted at Medicare.gov under "Part B costs."

Two things worth underlining:

1. IRMAA is based on Modified Adjusted Gross Income (MAGI) — your AGI plus a few add-backs like tax-exempt interest. 2. Crossing a threshold by even one dollar bumps you into the next tier. It's a cliff, not a slope.

Life changes that can lower your surcharge

Because IRMAA looks back two years, it can feel unfair when your income has since fallen. The good news: Medicare allows you to request a new decision if you've had a qualifying life-changing event. These include:

• Marriage, divorce, or the death of a spouse
• You or your spouse stopped working or reduced hours
• Loss of income-producing property (not from a sale)
• Loss or reduction of a pension
• An employer settlement payment from a closed or bankrupt employer

To request a review, file Form SSA-44 with the Social Security Administration and include documentation. Many people don't realize this form exists — and it's the single most common way to get an unfair-feeling surcharge corrected.

What this means during Annual Enrollment

Mount Pleasant is in Isabella County, where residents can compare stand-alone Part D drug plans and Medicare Advantage plans with drug coverage during AEP (Oct. 15 – Dec. 7). A few reminders as you shop:

• IRMAA doesn't change based on which plan you pick. You'll owe the same surcharge whether you're in Original Medicare with a Part D plan or in Medicare Advantage with drug coverage.
• The Part D surcharge is billed separately. If you have Medicare Advantage that includes drugs, you'll still get a bill (usually from Social Security or Medicare) for the Part D portion of IRMAA on top of your plan premium.
• Program-wide Part D changes worth knowing: the annual out-of-pocket cap on covered drugs is $2,100 in 2026 and $2,400 in 2027, the maximum deductible is $615 in 2026 and $700 in 2027, and the old coverage gap ("donut hole") is gone. The optional Medicare Prescription Payment Plan lets you spread drug costs across the year in monthly installments.

Common mistakes to avoid

• Ignoring the SSA letter. If you disagree, you have 60 days to appeal. Don't wait.
• Assuming Roth conversions or big one-time capital gains "don't count." They can push MAGI over a threshold and cause a two-year-later surcharge.
• Forgetting to update Social Security after a life change. Retiring is a common trigger for filing SSA-44.
• Confusing IRMAA with your plan premium. Switching plans won't reduce IRMAA — only an income change or successful appeal will.