Medicare Part D
The cheapest premium and the cheapest drug plan are rarely the same thing.
Part D is Medicare's prescription drug coverage. A standalone Part D plan pairs with Original Medicare or a supplement; Advantage plans usually build it in. The plan that costs you least depends far more on your specific drugs than on the monthly premium.
In plain language
What this actually is
Part D is run by private insurers under Medicare rules. Each plan publishes a formulary — the list of drugs it covers and the tier, and therefore the price, of each one.
Two plans with similar premiums can price the same prescription very differently. A single drug can sit on a cheap tier in one plan and an expensive tier in another, which is why the premium alone tells you almost nothing.
Since 2025, Part D has a hard annual out-of-pocket cap on covered drugs — a genuine change that protects people with high drug costs for the first time.
Suitability
Who needs to think hard about Part D
- Anyone on Original Medicare or a supplement who takes prescriptions
- People whose medications changed in the last year
- Anyone who has never enrolled and could face a permanent late penalty
- Those with high drug costs who benefit most from the new out-of-pocket cap
Eligibility
Enrolling and avoiding the penalty
You are eligible once you have Part A or Part B. Going without creditable drug coverage can add a permanent penalty to your premium.
- Enroll during your Initial Enrollment Period around age 65
- Change plans each year during Annual Enrollment, October 15 to December 7
- The late-enrollment penalty is permanent and grows the longer you wait
- A Special Enrollment Period may apply if you lose other creditable coverage
Timing
The clock that matters
Part D plans are chosen and changed during the Medicare Annual Enrollment Period, and the review is worth doing every single year.
- Aug
- Sep
- Oct 15
- Nov
- Dec 7
- Jan 1
Compare plans October 15 – December 7; new coverage starts January 1.
The honest picture
What it does well, and where it falls short
Both columns matter. A product described only by its advantages has been sold to you, not explained.
What it does well
- Real cost control
- The right plan can move an expensive prescription to a cheaper tier and save far more than any premium difference.
- An out-of-pocket cap
- Covered drug spending is now capped for the year — a hard ceiling that did not exist before 2025.
- Extra help may apply
- Lower-income beneficiaries can qualify for programs that cut or eliminate drug costs; we check whether you do.
Limitations worth knowing
- Formularies change yearly
- The tier your drug sits on can move every January, so a plan that was cheapest last year may not be this year.
- Premium is misleading
- A low premium with poor formulary placement for your drugs can cost far more overall than a higher-premium plan.
- The penalty is permanent
- Going without creditable coverage adds a surcharge to your premium for as long as you have Part D.
How we work through it
The order we do things in
-
List your medications
We start from your actual prescriptions, doses and preferred pharmacy — the inputs that decide the real cost.
-
Price the total
We compare plans on your all-in yearly cost, not the premium, and put it in writing.
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Check for extra help
If your income may qualify you for assistance, we check it before anything else.
-
Re-run it every year
Formularies move annually, so the review is a yearly habit, not a one-time task.
Where we help
Available across all seven states we serve
Medicare Part D guidance is available to clients in every state we are licensed in. Our home base is northeast Wisconsin — the Fox Valley, Green Bay and the Lakeshore — and we work remote-first, by phone and video, right across every state on the list.
Questions
Medicare Part D questions
Why not just pick the lowest premium?
Because the premium ignores how your specific drugs are priced. A low-premium plan can place your prescription on an expensive tier and cost you more overall.
What is the late-enrollment penalty?
If you go without creditable drug coverage after you're first eligible, Medicare adds a permanent surcharge to your Part D premium that grows the longer you wait.
Do I need Part D with a supplement?
Usually yes. Medicare Supplement policies do not include drug coverage, so a standalone Part D plan pairs with them.
Related
Usually considered alongside this
We do not offer every plan available in your area. Any information we provide is limited to those plans we do offer in your area. Please contact Medicare.gov, 1-800-MEDICARE, or your State Health Insurance Assistance Program (SHIP) to get information on all of your options. Benefits Empire is not connected with or endorsed by the U.S. government or the federal Medicare program.
Let's price your drug plan on your actual prescriptions
Bring your medication list and we will compare plans on total yearly cost — not the premium. No fee to do it.