Medicare Part D

Also known as: Medicare Prescription Drug Coverage

Prescription drug coverage offered by private plans that follow Medicare rules, either separately or through most Medicare Advantage plans.

Medicare Part D helps pay for outpatient prescription drugs. You can join a separate Part D plan with Original Medicare, or receive drug coverage through most Medicare Advantage plans.

Each plan has its own formulary, drug tiers, pharmacy network, and coverage rules.
No Part D plan can charge more than a $615 deductible in 2026, although some plans charge less or no deductible.
After the deductible, you generally pay 25% of covered drug costs until your qualifying out-of-pocket spending reaches $2,100 in 2026.
After reaching that threshold, catastrophic coverage begins and you pay nothing for covered Part D drugs for the rest of the calendar year.

The Medicare Prescription Payment Plan can spread out-of-pocket drug costs across the calendar year. It changes when you pay, not the total amount you owe.

Compare plans with your real medication list. Check each drug's tier, restrictions, preferred pharmacies, and full yearly cost instead of choosing by premium alone.

See the official Medicare Part D cost guide for the current coverage stages and amounts.

Example

A person compares two Part D plans using the same prescriptions. The plan with the lower premium costs more for the year because one medication sits on a higher tier at the person's pharmacy.

Good to Know

The $2,100 limit applies to qualifying out-of-pocket spending for covered Part D drugs in 2026. It does not include the plan premium or drugs the plan does not cover.

Related Terms

Medicare Part A — Hospital insurance that helps cover inpatient hospital care, limited skilled nursing facility care, hospice, and some home health care.

Medicare Part B — Medical insurance that helps cover doctors, outpatient care, preventive services, medical equipment, and many tests and treatments.

Medicare Part C (Medicare Advantage) — Medicare Advantage, a private-plan alternative for receiving Part A and Part B benefits, usually with Part D drug coverage included.