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 "A" — 7 terms

A

ABN (Advance Beneficiary Notice of Noncoverage)

Medicare Basics

A written notice that a doctor or supplier gives you before providing a service that Medicare may not pay for. If you sign the ABN, you agree to pay for the service yourself if Medicare denies the claim. You have the right to refuse the service.

Also known as: ABN, Advance Beneficiary Notice

Acute Care

Part A

Short-term medical treatment for a severe injury, illness, or recovery from surgery. Typically provided in a hospital setting. Medicare Part A covers inpatient acute care stays when medically necessary.

Annual Enrollment Period (AEP)

Enrollment

The period each year from October 15 through December 7 when Medicare beneficiaries can change their Medicare Advantage or Part D drug plans. Changes take effect January 1 of the following year.

Also known as: Fall Open Enrollment

Annual Notice of Change (ANOC)

Enrollment

A document that Medicare Advantage and Part D plans must send to enrollees by September 30 each year. It outlines any changes to the plan's costs, coverage, or service area that will take effect January 1.

Also known as: ANOC

Annual Wellness Visit

Part B

A yearly visit with your doctor covered by Medicare Part B at no cost to you. Your doctor creates or updates a personalized prevention plan based on your current health. Not the same as a physical exam; it focuses on health risk assessment and prevention planning.

Also known as: AWV

Appeal

Medicare Basics

A formal request you make when you disagree with Medicare's decision about coverage or payment for a service. You have the right to appeal any coverage denial, and there are multiple levels of appeal available.

Assignment

Providers & Plans

An agreement by a doctor, supplier, or provider to accept the Medicare-approved amount as full payment for a covered service. Providers who accept assignment cannot bill you for more than that amount, aside from normal deductibles and coinsurance.

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