108 Medicare Terms Defined

Medicare Glossary

Plain-English definitions for every Medicare term — from ABN to ZIP enrollment. No jargon, no confusion.

Terms starting with "I" — 4 terms

I

Independent Payment Advisory Board

Part D

The point at which your total drug spending under Part D reaches a set threshold, after which you enter the coverage gap phase. This limit applies to the combined spending by you and your plan.

Also known as: ICL

Initial Enrollment Period (IEP)

Enrollment

The 7-month window around your 65th birthday during which you can first sign up for Medicare. It includes the 3 months before your birthday month, your birthday month, and the 3 months after. Enrolling during the first 3 months gets you the earliest coverage start.

Also known as: IEP

Inpatient Care

Part A

Care you receive when you are formally admitted to a hospital. Medicare Part A covers inpatient hospital care after you meet your deductible. Being in a hospital as an inpatient is different from outpatient observation status, which is covered under Part B.

IRMAA (Income-Related Monthly Adjustment Amount)

Costs & Coverage

An extra amount added to your Part B and Part D premiums if your income is above a certain threshold, based on the tax return from two years earlier. IRMAA is reassessed annually and can be appealed after certain life-changing events like retirement.

Also known as: IRMAA

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