Medicare Part D

Medicare Part B and D surcharges facing Columbia retirees

COLUMBIA, Mo. — As Medicare's Annual Enrollment Period runs through Dec. 7, higher-earning retirees in mid-Missouri are getting a fresh look at something that can quietly reshape their 2026 budget: the income-related surcharges added to Part B and Part D premiums. For 2026, those surcharges — known as IRMAA — kick in once income crosses $109,000 for a single filer, and the amount you owe is based on the tax return you filed two years ago.

What IRMAA actually is

IRMAA stands for the Income-Related Monthly Adjustment Amount. It's not a separate bill — it's an extra amount added to your standard Part B premium and, if you have drug coverage, to your Part D premium. Most people with Medicare pay only the standard Part B premium. But if your income is above the threshold, Social Security adds a surcharge on top.

The key thing to remember: IRMAA is based on your Modified Adjusted Gross Income (MAGI) from two years earlier. So your 2027 premiums will reflect what you reported on your 2025 tax return.

The 2026 income thresholds (2027 brackets pending) (2027 brackets pending)

For 2026, the first IRMAA tier begins when a single filer's MAGI is above $109,000, or above $218,000 for a married couple filing jointly. From there, the surcharge grows in steps as income rises, all the way up to the top tier for the highest earners.

Both parts are affected. If you owe IRMAA, you'll see one adjustment applied to Part B and a separate adjustment applied to Part D — even if your Part D coverage is through a Medicare Advantage plan that includes drugs. The Part D surcharge is paid to Medicare, not to your plan.

Why this matters right now in Columbia

Columbia is in Boone County, where retirees choosing between Original Medicare with a stand-alone drug plan and a Medicare Advantage plan with drug coverage sometimes forget that IRMAA follows them either way. Switching plans during AEP doesn't change your surcharge — only your income does.

A few Part D numbers are worth knowing while you compare coverage for 2027:

• The Part D out-of-pocket cap is $2,100 in 2026 and $2,400 in 2027. Once your covered drug spending hits that amount, you pay nothing for covered drugs the rest of the year.
• The Part D maximum deductible is $615 in 2026 and $700 in 2027.
• The coverage gap (the old "donut hole") is gone. Part D now has three phases instead of four.

If paying a big pharmacy bill in one month is a strain, ask about the Medicare Prescription Payment Plan, a new option that spreads your out-of-pocket drug costs into monthly installments across the year at no extra charge.

What to do if your income has dropped

IRMAA can feel unfair when it's based on income from a year you were still working. The good news: Social Security allows appeals for certain "life-changing events," including retirement, the death of a spouse, divorce, or loss of pension income.

You'd file Form SSA-44 with documentation. If approved, Social Security recalculates your surcharge using your more recent income. It's one of the most overlooked tools available to newly retired Medicare beneficiaries.

Where to get local, personalized help

For Boone County residents, Missouri's CLAIM program (the state's SHIP) offers free, unbiased Medicare counseling. Counselors can walk you through how IRMAA is calculated, what your Part D options look like, and whether an appeal makes sense in your situation.

You can also compare plans and check drug coverage at medicare.gov/plan-compare, or call 1-800-MEDICARE (1-800-633-4227), available 24/7.