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2026 IRMAA Brackets — Based on 2024 Income

IRMAA Medicare Surcharge Calculator

Find out if your income triggers Medicare Part B and Part D surcharges — and how much you can convert to Roth without crossing into a higher IRMAA bracket.

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IRMAA applies to Medicare enrollees (age 65+). If under 65, this calculator shows what your surcharges will be.

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2026 IRMAA is based on your 2024 income (2-year lookback). Find MAGI on your 2024 tax return, Form 1040 line 11.

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Enter the amount you plan to convert from Traditional IRA/401(k) to Roth. This adds to MAGI and may increase your IRMAA tier.

What Is IRMAA and Why Does It Matter?

If you're on Medicare and your income is above certain thresholds, you pay more for Part B (medical insurance) and Part D (prescription drug coverage). These extra charges are called IRMAA — the Income-Related Monthly Adjustment Amount.

For 2026, IRMAA is determined by your 2024 Modified Adjusted Gross Income (MAGI). This 2-year lookback means that a large Roth conversion, capital gain, or retirement distribution in 2024 can unexpectedly increase your Medicare premiums in 2026.

How IRMAA Affects Roth Conversion Planning

Roth conversions are a powerful retirement tax strategy — but they add to your MAGI. Converting too much in a single year can push you into a higher IRMAA tier, adding hundreds or thousands of dollars in annual Medicare surcharges. The key is to find the sweet spot: convert as much as possible while staying within your current IRMAA bracket.

This calculator shows you exactly how much headroom you have before the next bracket, and what happens to your IRMAA if you proceed with a specific conversion amount.

The 6 IRMAA Tiers

IRMAA has 6 tiers. Tier 1 is the standard premium (no surcharge). Tiers 2–6 add progressively higher monthly surcharges to both Part B and Part D. For single filers, the Tier 1 threshold is $109,000; for married filing jointly, it's $218,000. The top tier (Tier 6) applies to individuals with MAGI over $500,000 or couples over $750,000.

Married Filing Separately? MFS filers face compressed IRMAA brackets. You jump from Tier 1 (≤$109,000) directly to Tier 5 ($109,001–$391,000), skipping Tiers 2–4 entirely. This can result in significantly higher surcharges.

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Frequently Asked Questions

What is IRMAA?

IRMAA (Income-Related Monthly Adjustment Amount) is a surcharge added to your standard Medicare Part B and Part D premiums if your income exceeds certain thresholds. It's based on your Modified Adjusted Gross Income (MAGI) from 2 years prior — so your 2024 income determines your 2026 IRMAA.

How does the 2-year lookback work?

Medicare uses your tax return from 2 years ago to determine your IRMAA bracket. For 2026 premiums, Social Security looks at your 2024 MAGI (from the tax return you filed in 2025). This means a large Roth conversion or capital gain in 2024 won't affect your Medicare premiums until 2026.

Can Roth conversions trigger higher IRMAA?

Yes. Roth conversions add to your MAGI, which can push you into a higher IRMAA tier. This calculator helps you find the maximum Roth conversion amount that keeps you in your current IRMAA bracket, so you can optimize conversions without unnecessary surcharges.

What is a life-changing event (LCE) appeal?

If you've experienced a qualifying life-changing event — such as marriage, divorce, death of a spouse, work stoppage, or loss of pension — you can file Form SSA-44 to request that Social Security use a more recent year's income instead of the 2-year lookback. This can reduce or eliminate IRMAA surcharges.

How accurate is this calculator?

This calculator uses the official 2026 IRMAA brackets published by CMS and SSA. The Part B standard premium ($202.90/month) and surcharge amounts are based on the latest available data. Actual premiums may vary slightly. Always confirm with Social Security or your Medicare plan for exact amounts.