Medicare Part D – Prescription Drug Coverage

Affordable Medication Coverage for Your Health Needs

Medicare Part D is a standalone prescription drug plan that helps lower the cost of medications. If you are enrolled in Original Medicare (Part A and/or Part B), Medicare Part D can provide essential prescription drug coverage to help you manage healthcare costs.



Choosing the right Medicare Part D plan ensures that your medications remain affordable and accessible, allowing you to focus on your health without financial stress.

What Is Medicare Part D?

Medicare Part D is a federal program run by private insurance companies that provides coverage for prescription drugs, vaccines, and select medications. It is available as:

A Standalone Plan (PDP)

If you have Original Medicare (Parts A & B)

Included in Medicare Advantage (MA-PD)

If you have a Medicare Advantage Plan

Who Is Eligible for Medicare Part D?

To enroll in Medicare Part D, you must:


  • Be enrolled in Medicare Part A and/or Part B
  • Live within the service area of the plan you’re selecting
  • Not have other creditable prescription drug coverage


If you already have drug coverage through an employer, VA, or retiree plan, check if it meets Medicare’s “creditable coverage” standard before enrolling in Part D.

What Does Medicare Part D Cover?

Medicare Part D covers a wide range of brand-name and generic drugs, including:


  • Medications for chronic conditions like diabetes, high blood pressure, and heart disease
  • Vaccines not covered under Part B (such as shingles)
  • Cancer treatments, mental health medications, and immunosuppressants
  • Antibiotics, antivirals, and other common prescriptions
Each Medicare Part D plan has a formulary (list of covered drugs) categorized into tiers that determine your out-of-pocket costs.
Tier Medication Type Cost Level
Tier 1 Preferred Generic Lowest copay
Tier 2 Non-Preferred Generic Low copay
Tier 3 Preferred Brand Moderate copay
Tier 4 Non-Preferred Brand Higher copay
Tier 5 Specialty Drugs Highest cost

How Much Does Medicare Part D Cost?

Costs vary depending on the plan, drug coverage, and location, but typically include:


✔ Monthly Premium – Varies by plan and provider. National average: $31.50/month
✔ Annual Deductible – Up to $505 per year (some plans have lower or $0 deductibles)
✔ Copayments & Coinsurance – Based on drug tiers and plan structure

Understanding the Medicare Part D Coverage Phases

Medicare Part D has four cost phases that determine how much you pay for prescriptions:


  1. Deductible Phase – You pay full cost of drugs until you meet your plan’s deductible.
  2. Initial Coverage Phase – You pay copays or coinsurance for covered medications.
  3. Coverage Gap (Donut Hole) – You pay 25% of drug costs after reaching a spending limit ($5,030 in 2024).
  4. Catastrophic Coverage – You pay no more than 5% of drug costs after exceeding annual out-of-pocket limits.


Choosing a plan with low copays, a manageable deductible, and strong formulary coverage can help you save on prescriptions.

When Can You Enroll in Medicare Part D?

Medicare Part D follows specific enrollment periods to ensure you can sign up or switch plans at the right time.


  • Initial Enrollment Period (IEP) – When you first become eligible for Medicare (3 months before and after your 65th birthday).
  • Annual Enrollment Period (AEP) – October 15 – December 7 (Change or enroll in a new plan).
  • Medicare Advantage Open Enrollment (OEP) – January 1 – March 31 (Switch to a different Medicare Advantage plan with drug coverage).
  • Special Enrollment Period (SEP) – If you lose creditable drug coverage, move to a new state, or qualify for Extra Help.


If you don’t enroll in Medicare Part D when first eligible and don’t have other creditable coverage, you may face a lifetime late enrollment penalty.

Medicare Part D vs. Medicare Advantage Prescription Drug Plans (MA-PD)

Feature Standalone Medicare Part D Medicare Advantage (MA-PD)
Coverage Prescription drugs only Medical + prescription drug benefits
Premiums Separate from Medicare Part B Included in Medicare Advantage
Provider Network Available with any Medicare doctor Limited to the plan’s network
Costs Varies by drug tier Can have lower overall costs
Additional Benefits None Dental, vision, hearing, and more

If you prefer to keep Original Medicare and only need prescription drug coverage, a standalone Medicare Part D plan is the best option. If you want all-in-one coverage, a Medicare Advantage plan with drug benefits (MA-PD) may be a better fit.

Why Choose Insured Carolina for Medicare Part D?

Choosing the right Medicare Part D plan can be complex, but our experts at Insured Carolina are here to help.


  • Compare multiple plans to find the best fit for your prescriptions
  • Avoid costly penalties by enrolling at the right time
  • Get expert guidance on managing drug costs and plan changes
  • Find extra savings with Medicare’s Extra Help program for lower-income beneficiaries


We work with top insurance carriers to find the most affordable plan that covers your medications.