All terms
Glossary · compliance
IRMAA (Medicare Premium Income Surcharge)
IRMAA is a Medicare premium surcharge based on income from two years prior. Crossing thresholds can add hundreds per month to your premiums.
IRMAA (Income-Related Monthly Adjustment Amount) is a surcharge on Medicare Part B and Part D premiums that kicks in at higher incomes. The income basis is your MAGI from two years prior — so 2026 IRMAA is determined by 2024's MAGI.
2026 thresholds (approximate)
- Single: surcharges begin at $106,000 MAGI
- Married filing jointly: surcharges begin at $212,000 MAGI
The full schedule has 5 tiers; the top tier is roughly $4,300/year per person of extra premium for highest-income retirees.
Why it matters for tax planning
A single Roth conversion or large capital gain that pushes MAGI just above an IRMAA threshold can cost $1,000-$5,000 of extra Medicare premiums two years later. The "cliff" structure makes it a hard threshold rather than a smooth tax.
Planning levers
- Cap Roth conversions just under the next IRMAA tier
- Bunch capital gains in non-IRMAA-relevant years (pre-Medicare or far in advance)
- Tax-loss harvesting can keep MAGI lower in retirement
- Charitable giving (QCDs from IRA at 70.5+, DAF contributions) reduces MAGI
Form SSA-44
If your income drops due to a life event (retirement, death of spouse, work reduction), you can file Form SSA-44 to ask Social Security to use the more recent year's income.
Sources
- Medicare Part B + D premium tables
- Form SSA-44
Related terms
- Roth conversion ladderConverting Traditional IRA to Roth across multiple years can fill lower tax brackets before required minimum distributions hit at age 73.
- NIITA 3.8% surtax on investment income when modified AGI exceeds $200K (single) or $250K (MFJ). Capital gains, dividends, interest, and rental income may be subject.
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