Medicare Part D

2027 IRMAA Thresholds for Idaho Falls Medicare

IDAHO FALLS, Idaho — As Medicare's Annual Enrollment Period runs through Dec. 7, many people in eastern Idaho are opening letters from Social Security and spotting an unfamiliar line item: an income-related surcharge on their Part B and Part D premiums. The 2027 income thresholds that trigger those surcharges have not yet been published — CMS typically announces them in the fall, usually in November — and understanding how the surcharges work can prevent an unpleasant surprise come January.

The surcharge is called IRMAA — the Income-Related Monthly Adjustment Amount. It's not a penalty. It's an extra amount higher-income Medicare beneficiaries pay on top of the standard Part B and Part D premiums.

What IRMAA Is, in Plain Terms

Most people on Medicare pay the same standard Part B premium and only the plan premium for Part D. But if your income is above a certain level, Social Security adds an extra monthly charge to both. That extra charge is IRMAA.

Here's the part that trips people up: IRMAA is based on your tax return from two years ago. Your 2027 surcharge will be calculated from your 2025 income — specifically your Modified Adjusted Gross Income (MAGI), which is your AGI plus any tax-exempt interest.

The 2027 Income Thresholds

For 2026, IRMAA kicks in when a single filer's MAGI is above $109,000, or above $218,000 for a married couple filing jointly. Below those numbers, you pay the standard premiums with no surcharge.

Above the first threshold, IRMAA is tiered. The higher your income climbs, the higher the surcharge on both Part B and Part D. There are five tiers in total, with the top tier reserved for single filers with incomes at or above roughly $500,000 (and $750,000 for joint filers). Social Security publishes the current dollar amount for each tier at ssa.gov, and Medicare posts them at medicare.gov.

Two important notes:

• The Part D surcharge is paid in addition to whatever your Part D plan's premium is — even if that plan otherwise has a low premium.
• If you have Medicare Advantage with drug coverage, the Part D portion of IRMAA still applies.

Why Your Letter Might Feel Out of Date

Because IRMAA looks back two years, a lot can change between the tax return being used and the year you're actually paying. If you retired, sold a business, lost a spouse, or had another major income drop, the surcharge based on 2024 income may no longer reflect your reality.

The good news: you can ask Social Security to reconsider. Form SSA-44 lets you request a new IRMAA determination after a "life-changing event," which includes things like:

• Marriage, divorce, or the death of a spouse
• Work stoppage or work reduction
• Loss of pension income
• Loss of income-producing property (not due to a sale)

You'll need documentation, but the process is straightforward, and it's one of the most under-used tools in Medicare.

How This Fits With Other 2027 Changes

IRMAA isn't the only Part D number worth knowing this year. For 2026:

• The Part D out-of-pocket cap is $2,400 in 2027. Once you hit it, you pay nothing for covered drugs the rest of the year.
• The Part D maximum deductible is $700 in 2027.
• The old 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 across the calendar year in monthly installments, at no added cost. You have to opt in.

These changes apply nationwide, including here in Idaho Falls, which is in Bonneville County. The 2027 plan lineup for stand-alone Part D plans and Medicare Advantage plans with drug coverage is detailed in each plan's Annual Notice of Change and on Medicare.gov's Plan Finder.

What to Do Before Dec. 7

If you think IRMAA may apply to you in 2027:

1. Pull your 2024 tax return and check your MAGI against the $109,000 / $218,000 thresholds. 2. If you had a life-changing event since 2024, download Form SSA-44 from ssa.gov. 3. When comparing Part D or Medicare Advantage plans at medicare.gov/plan-compare, remember the surcharge is on top of any plan premium. 4. Consider whether the Medicare Prescription Payment Plan might smooth out a big January prescription bill.