Medicare Glossary: Definitions You Need to Know
AARP’s updated Medicare glossary explains the 2026 Part D out-of-pocket limit of $2,100 and how IRMAA surcharges can raise Part B and Part D premiums for higher-income beneficiaries.
Source: AARP ·
Your income today determines what you'll pay for Medicare tomorrow—and the gap between what you think you'll owe and what you actually owe can be substantial. If you're in your 50s building toward retirement, IRMAA surcharges mean that higher earners face increased Part B and Part D premiums based on tax return income from two years prior. A $2,100 out-of-pocket limit on Part D prescriptions sounds manageable until you realize surcharges can stack on top of it, making medication costs a meaningful piece of retirement budgeting. Worth running the numbers on how your current income trajectory might trigger IRMAA once you claim Social Security and tap retirement accounts.
- •The 2026 Part D out-of-pocket limit is $2,100 for covered prescriptions.
- •IRMAA can increase both Part B and Part D premiums.
- •Income reported on tax returns is used to determine whether the surcharge applies.
Retirees and people planning Roth conversions should account for potential IRMAA exposure and the annual prescription-drug spending cap.