Watch Phil Capriotti on The Wealth Council

LEARN MORE
CLIENT PORTAL

Medicare Prescription Drug Coverage (Part D): What It Covers, What It Costs, and How to Choose the Right Plan

If you take even one regular medication, Medicare prescription drug coverage can make a meaningful difference in your monthly budget. But Part D can also feel confusing because plans change, formularies change, and costs can vary widely from one person to the next—even within the same ZIP code.

This guide explains how Medicare prescription drug coverage works, what it typically covers, and the key steps to choosing a plan that fits your medications and your budget.

What Is Medicare Part D?

Medicare Part D is the part of Medicare that helps cover outpatient prescription drugs (the medications you pick up at a pharmacy or receive by mail order).

You can get drug coverage in one of two main ways:

  1. Standalone Part D Plan (PDP):
    Added to Original Medicare (Part A and Part B).

  2. Medicare Advantage Plan with Drug Coverage (MAPD):
    A Medicare Advantage plan (Part C) that includes prescription coverage.

If you want prescription drug coverage, you generally need to enroll in one of these options—Original Medicare by itself does not include routine outpatient drug coverage.

What Part D Typically Covers (and What It Doesn’t)

Commonly covered:

Most Part D plans cover a broad range of medications, including:

  • Brand-name and generic drugs

  • Common maintenance medications (blood pressure, cholesterol, diabetes, etc.)

  • Many specialty medications (depending on the plan)

  • Vaccines (many adult vaccines are covered under Part D)

Not typically covered:

Part D plans usually do not cover:

  • Drugs administered in a hospital or skilled nursing setting (often Part A)

  • Many drugs administered in a doctor’s office (often Part B)

  • Over-the-counter medications

  • Certain categories that may be excluded under federal rules (varies by plan and situation)

How Part D Plans Decide What You Pay

Part D costs are not “one-size-fits-all.” Your total cost depends on your plan, your medications, your pharmacy, and your usage.

Here are the biggest factors:

1) Monthly premium

Some plans have low premiums, but that doesn’t automatically mean lower total cost. A higher premium plan can sometimes reduce your copays enough to save money overall—especially for people with multiple prescriptions.

2) Deductible

Many plans have a deductible (some don’t). If your plan has one, you may pay more upfront until the deductible is met.

3) Copays and coinsurance

Once coverage starts, you’ll typically pay either:

  • a copay (fixed dollar amount), or

  • coinsurance (a percentage of the drug cost)

4) The plan’s formulary (drug list)

Each plan has a formulary—a list of covered drugs. Drugs are usually placed into tiers, and tiers influence what you pay:

  • Lower tiers (preferred generics) usually cost less

  • Higher tiers (non-preferred brands or specialty meds) cost more

5) Pharmacy network: preferred vs. standard

Many plans offer better pricing at preferred network pharmacies. Using a non-preferred pharmacy can significantly increase costs, even if the plan still “covers” the medication.

6) Prior authorization, step therapy, and quantity limits

Some medications may require extra steps:

  • Prior authorization: the plan must approve the drug before it’s covered

  • Step therapy: you may need to try a lower-cost alternative first

  • Quantity limits: limits on how much you can get at one time

The Most Common Mistake: Choosing by Premium Alone

It’s tempting to pick the lowest premium plan—but that can backfire if:

  • your drugs aren’t covered (or are covered on a high tier),

  • your pharmacy isn’t preferred, or

  • your copays are much higher than a slightly higher premium plan.

The best plan is usually the one with the lowest estimated total annual cost for your specific medication list.

How to Choose the Right Part D Plan

Here’s a simple checklist that works well for most beneficiaries:

Step 1: Make a complete medication list

Include:

  • drug name

  • dosage

  • frequency

  • whether you use name brand or generic

  • the pharmacy you prefer (or if you’re open to switching)

Step 2: Confirm each medication is covered

Look for:

  • whether it’s on the plan’s formulary

  • what tier it’s on

  • any restrictions (prior authorization, step therapy, quantity limits)

Step 3: Compare costs at your pharmacy

Check pricing at:

  • preferred network pharmacies

  • mail order (if you’re open to it)

Step 4: Consider flexibility and predictability

If you prefer stable budgeting, a plan with slightly higher premium but lower copays may feel easier month-to-month.

Step 5: Re-check every year

Plans can change their formularies, tiers, and pharmacy networks. Even if your plan worked great last year, it’s smart to review it annually.

When You Can Enroll or Change Part D

You can typically enroll or change plans:

  • When you first become eligible for Medicare

  • During the annual enrollment period (commonly in the fall)

  • During certain special enrollment periods (SEPs), depending on circumstances

  • If you qualify for Extra Help or certain other programs (rules vary)

If you go without creditable drug coverage for too long, you may face a late enrollment penalty, so timing matters.

Extra Help: A Program Many People Miss

If you have limited income and resources, you may qualify for Extra Help (Low-Income Subsidy), which can reduce:

  • premiums

  • deductibles

  • copays

Many people who qualify don’t realize it, so it’s worth checking.

Quick Takeaways

  • Part D helps cover outpatient prescription drugs through standalone plans or Medicare Advantage plans with drug coverage.

  • Your total cost depends on your medications, your pharmacy, and the plan’s formulary and tiers—not just the premium.

  • The “best” plan is usually the one with the lowest total estimated annual cost for your drug list.

  • Reviewing your coverage yearly can prevent surprise cost increases.

Share:

View the Latest Posts:

Beyond the Premium: Five Questions to Ask Before Choosing a Medicare Plan

A low monthly premium can catch your attention. But it cannot tell you whether a Medicare plan fits your life. The questions that matter often come later: Can you keep your doctor? What will your prescriptions cost? How does coverage work when you travel? What might you pay if you need more care than expected? Whether you are approaching Medicare eligibility or reviewing your current coverage, looking beyond the advertised price can help you make a more informed decision. 1. What Could I Spend Over the Entire Year? A monthly premium is only one part of your healthcare budget. Deductibles, copayments, coinsurance, and prescription expenses also deserve attention. When comparing coverage, consider two scenarios: a year when you mainly need routine care and a year when you need more frequent treatment. Ask questions such as: What would I pay to see a specialist? What are the costs for outpatient procedures

Does Your Medicare Plan Still Fit Your Life? What to Review Before You Renew

The Medicare plan you chose last year may have made perfect sense at the time. But what happens when your prescriptions change, you start seeing a specialist, or your plan updates its costs and coverage? It is easy to assume that keeping the same plan means everything stays the same. Medicare health and prescription drug plans, however, can change from year to year—and your healthcare needs can change right along with them. An annual review gives you an opportunity to make sure your coverage still fits your life. Medicare’s fall Open Enrollment runs from October 15 through December 7, with changes generally taking effect January 1 of the following year. That means this fall’s enrollment decisions affect your 2027 coverage. Start With What Changed in Your Life Before comparing plans, take a few minutes to think about your healthcare over the past year. Have you started taking a new medication?

Medicare Changes for 2027: 7 Things You Need to Review Before Keeping Your Current Plan

Your Medicare coverage may look the same on the surface, but important changes to your benefits, prescription costs, and provider networks could affect what you pay next year. For millions of Americans, Medicare provides essential health coverage and greater confidence about the future. But one of the biggest mistakes Medicare beneficiaries can make is assuming that the plan they have today will automatically be their best option tomorrow. As we approach 2027, Medicare beneficiaries have important decisions to make. Insurance companies can adjust premiums, change prescription drug coverage, modify provider networks, and update benefits from one year to the next. The good news? You have an opportunity to review your options before these changes take effect. Medicare’s Annual Enrollment Period runs from October 15 through December 7, 2026, giving eligible beneficiaries the opportunity to review and make changes to their Medicare health and prescription drug coverage for 2027. Changes made

Your Medicare Plan May Be Changing—Even If Your Health Hasn’t

You’re happy with your doctors. Your prescriptions haven’t changed. Your Medicare coverage worked well this year. So, is reviewing your plan really necessary? It’s a worthwhile step. Your healthcare needs may stay the same while your plan’s costs and coverage change. Taking time to review the details this fall can help you make a more informed decision about the year ahead. Medicare Open Enrollment runs October 15 through December 7 each year. Changes made during this period take effect January 1, as long as the plan receives your enrollment request by December 7. That means this fall’s enrollment decisions affect your coverage for 2027. Start With the Notice You Might Be Tempted to Skip If you have a Medicare Advantage or prescription drug plan, your plan sends an Annual Notice of Change, often called an ANOC, each fall. It explains changes to costs, coverage, and other plan details that begin