Medicare Part D

IRMAA & Medicare Premiums in Seattle, WA — 2027

SEATTLE — If your income has climbed in the last couple of years, your 2026 Medicare bill could look different than you expect. Starting in January, higher-income enrollees will again pay an extra monthly charge on top of their standard Part B and Part D premiums — a surcharge called the Income-Related Monthly Adjustment Amount, or IRMAA. For 2026, those extra charges begin once a single filer's income tops $109,000, or $218,000 for a married couple filing jointly.

Here's what Seattle-area readers need to know before the numbers show up on a Social Security statement.

What IRMAA actually is

IRMAA is not a separate bill or a penalty. It's an added amount tacked onto your monthly Part B premium and, if you have drug coverage, your Part D premium. Most people with Medicare pay the standard premium. Only about the top 8% of enrollees pay IRMAA in a given year.

Social Security decides who owes it based on the tax return you filed two years earlier. That means your 2027 IRMAA is based on your 2025 tax return — specifically your Modified Adjusted Gross Income (MAGI), which is your adjusted gross income plus any tax-exempt interest.

The 2027 income brackets

For 2026, IRMAA kicks in at these MAGI thresholds:

• Single filers: surcharges begin above $109,000
• Married filing jointly: surcharges begin above $218,000
• Married filing separately (who lived with a spouse): for 2026, surcharges begin at a much lower level, above roughly $106,000

From there, the surcharge steps up through five tiers. The highest tier applies to single filers with income of $500,000 or more, and joint filers at $750,000 or more. Each tier adds a set dollar amount to both your Part B premium and your Part D premium — the Part D piece is charged separately from whatever your drug plan costs.

The exact dollar amounts for each tier are published by CMS at medicare.gov. The 2027 figures are expected later this fall; always confirm the current figure there before making a decision.

Why it can catch people off guard

IRMAA surprises usually come from three places:

1. A one-time income spike two years ago — selling a home, cashing out stock, converting a traditional IRA to a Roth, or taking a large required minimum distribution. 2. The two-year lookback itself. Someone who retired in 2025 may still be paying IRMAA in 2026 based on their higher working-year income from 2024. 3. Crossing a bracket by a small amount. IRMAA is a cliff, not a slope. One extra dollar of MAGI can push you into the next tier and cost you hundreds more for the year.

When you can ask for a reduction

If you've had a life-changing event that lowered your income, you can ask Social Security to recalculate. Qualifying events include:

• Retirement or reduced work hours
• Death of a spouse
• Marriage or divorce
• Loss of a pension
• Loss of income-producing property (not from your own choice, like a sale)

The form is SSA-44, "Medicare Income-Related Monthly Adjustment Amount – Life-Changing Event." You'll need documentation, like a letter from an employer or a death certificate. If you disagree with the IRMAA determination itself — say, because your tax return was amended — you can file an appeal instead.

How IRMAA fits into the rest of your 2027 costs

IRMAA is only one piece of what you'll pay next year. A few other program facts worth keeping in mind for 2027:

• The Part D out-of-pocket cap is $2,100 for 2026 — a hard ceiling on what you pay for covered drugs at the pharmacy.
• The Part D maximum deductible is $615 in 2026 ($700 in 2027).
• The coverage gap (donut hole) is gone as of 2025; Part D now has three phases instead of four.
• The Medicare Prescription Payment Plan lets you spread drug costs into monthly installments at no added charge.

Seattle is in King County, where enrollees choose from a wide range of Medicare Advantage and stand-alone Part D plans during the Annual Enrollment Period, October 15 through December 7. If you're already in a Medicare Advantage plan, you also have the Medicare Advantage Open Enrollment Period from January 1 to March 31 to make one change.

Mistakes to avoid this fall

• Don't ignore the letter. Social Security mails an "Initial IRMAA Determination" notice. If your income has since dropped, act on it — don't just pay.
• Don't assume last year's bracket still applies. The thresholds are indexed and change most years.
• Don't forget tax-exempt interest. Muni bond income counts toward MAGI for IRMAA even though it's not taxed federally.
• Don't file SSA-44 for a one-time event like a Roth conversion — that's not a qualifying life-changing event, even though it can raise your MAGI significantly.