Medicare IRMAA Explained: How It Affects Part B Premiums

Medicare IRMAA Explained: How It Affects Part B Premiums

IRMAA can make Medicare feel more expensive than expected, especially when your premium is based on income from two years ago. Knowing how it works can help you plan for costs before enrollment surprises you.

Key Takeaways

• IRMAA is an added monthly surcharge for higher-income Medicare beneficiaries, and it can apply to both Part B and Part D premiums.
• Your 2026 IRMAA amount is based on your 2024 tax return, so retirement or other income changes may not be reflected automatically.
• If a qualifying life-changing event lowered your income, you may be able to ask Social Security to review your IRMAA amount.

Most people expect to pay a standard Medicare Part B premium. Then they get a notice showing a higher amount, and the difference isn't always explained clearly. That extra charge is called IRMAA (Income-Related Monthly Adjustment Amount), and it can catch retirees off guard if their income was higher two years ago than it is now.

What Does IRMAA Mean for Medicare Part B Premiums?

IRMAA is an extra monthly charge added to Medicare Part B and, in some cases, Part D prescription drug coverage. It doesn't replace your regular premium. Instead, it's added to the premium you already pay.

For 2026, the standard Part B premium is $202.90 per month. If your income is above certain thresholds, you'll pay that standard premium plus an IRMAA surcharge. The higher your income bracket, the higher the added amount.

This can feel frustrating because Medicare doesn't look at what you're earning right now first. It usually starts with the tax return the IRS has already sent to Social Security.

Why Does Medicare Use Income From Two Years Ago?

Medicare uses a two-year lookback because that's the most recent complete tax information available in the federal system. For 2026 premiums, that usually means your 2024 modified adjusted gross income, often called MAGI.

MAGI includes adjusted gross income plus certain tax-exempt interest. For many retirees, the number can be affected by wages, business income, capital gains, retirement account withdrawals, pension income, or the sale of a property.

That lookback can create a mismatch. You may be fully retired in 2026, but your premium may still be based on a higher income year from 2024. That's why it's important to review Medicare costs early instead of assuming the standard premium applies.

Which Income Changes Can Affect an IRMAA Appeal?

Not every income drop qualifies for a review, but Social Security does recognize certain life-changing events. These events can give you a reason to ask for a new IRMAA decision if your current income is lower than the tax return being used.

Common qualifying events include:

• Work stoppage, such as retirement
• Reduced work hours
• Marriage, divorce, or annulment
• Death of a spouse
• Loss of pension income
• Loss of income-producing property that was not at your direction
• Certain employer settlement payments

If one of these qualifying events applies, you may be able to file Form SSA-44 with Social Security. The form asks you to explain the event, estimate your updated income, and provide supporting documentation. Filing the form does not guarantee a lower premium, but it gives Social Security a way to review the charge.

How Can IRMAA Change Your Total Medicare Costs?

IRMAA is only one piece of your Medicare budget, but it's an important one because it repeats every month. A higher Part B premium can affect how affordable your full coverage feels, especially if you're also comparing Medicare Advantage, Medigap, and prescription drug options.

The right plan still depends on your providers, prescriptions, health needs, travel habits, and comfort with out-of-pocket risk. A higher Part B premium doesn't automatically make one plan type better than another, but it should be part of the full cost comparison.

It's also worth remembering that Original Medicare doesn't cover everything. Routine dental care, hearing aids, long-term custodial care, and some other costs may still need separate planning, so IRMAA shouldn't be the only number you review.

When Should You Review Your Medicare Premiums and Enrollment Options?

The best time to review Medicare premiums is before you enroll or before a new plan year begins. That gives you time to understand your Part B cost, check whether IRMAA applies, compare plan options, and ask questions before deadlines arrive.

If your income changed after retirement, don't wait until the higher premium becomes a financial strain. Gather your tax return, Social Security notice, retirement date, and any documents that support the life-changing event. Then you can contact Social Security to ask whether you qualify for an IRMAA review.

You should also look at enrollment timing. If your needs change later, special enrollment periods may apply in certain situations, but it's still easier to choose carefully from the start.

Need Help Understanding Medicare Costs in Sonoma County?

Trying to calculate your true Medicare costs on your own can quickly become overwhelming. At Sackett Insurance, we help Sonoma County residents map out the complete financial picture before they commit to a plan.

Our team breaks down how Part B premiums, IRMAA surcharges, supplemental insurance, and prescription drug plans interact, ensuring the numbers actually make sense for your retirement budget.

If you're approaching enrollment and want help comparing your out-of-pocket expenses, contact Sackett Insurance today to schedule a local Medicare consultation.