Medicare Star Ratings Explained: What the Stars Mean

Medicare star ratings, in one sentence: they're Medicare's yearly 1-to-5 quality score for Medicare Advantage and Part D plans — 5 stars is best, 1 star is lowest — published by CMS every fall so you can compare plan quality, not just price.

What Medicare Star Ratings Are, and What They Aren't

Every year, Medicare rates the quality of Medicare Advantage plans and Part D prescription drug plans. Each plan gets an overall Medicare star rating from 1 to 5 stars, plus a set of underlying measure scores that roll up into it. Five stars is the best score; one star is the lowest. CMS, the federal agency that runs Medicare, publishes the ratings so people with Medicare and their caregivers can compare plans on quality — not just on price and benefits.

Two things Medicare star ratings do not cover:

Original Medicare itself is not rated. The stars apply to the private Medicare Advantage and Part D plans, because those are the plans you choose among.
Stars don't set your costs. A high rating measures quality of service, not price. A 5-star plan can cost more or less than a 3-star plan. Check each plan's costs separately.

What Do the Stars Measure?

A plan's overall star rating rolls up many separate quality measures — scored against CMS-set thresholds and then weighted together into the 1-to-5 number you see on Plan Finder. Medicare Advantage plans with drug coverage are scored on up to 43 different measures; stand-alone drug plans on up to 12. In plain terms, the measures look at things like:

How well the plan helps members stay healthy — screenings, vaccines, and check-ups.
How well it manages long-term conditions like diabetes.
What members say about their own experience with the plan.
How many complaints the plan gets and how it handles customer service.
Drug safety and drug pricing accuracy (for plans with drug coverage).

For 2026, about 40% of Medicare Advantage drug plan contracts earned 4 stars or more, and roughly 64% of enrollees are in those higher-rated contracts. A rating of 4 stars or higher also qualifies a Medicare Advantage plan for a CMS quality bonus, which plans can pass on as extra benefits or lower costs.

Want the technical detail — the measure sets, data sources, and bonus-payment mechanics behind CMS's Medicare star ratings? See our professional reference, Star Ratings methodology, or the CMS technical documents.

Where to Find a Plan's Star Rating

Star ratings appear on Medicare.gov's Plan Finder, next to each plan, when you compare plans in your area. New ratings come out each fall. For example, the 2026 ratings were published on Plan Finder on October 9, 2025 — in time for Open Enrollment. Open Enrollment runs October 15 through December 7 each year.

Because the ratings are refreshed every year, check the current stars each fall even if you plan to stay put. A plan's score can go up or down from year to year.

What a 5-Star Plan Means for You

A 5-star rating comes with a special rule. If a 5-star Medicare Advantage plan or drug plan is available where you live, you can use a one-time Special Enrollment Period to switch into it — even outside Open Enrollment. You can use this chance once between December 8 and November 30 of the following year.

One trap to watch: if you use this switch to move from a Medicare Advantage plan that includes drug coverage to a 5-star plan that doesn't, you can lose your drug coverage — and you may face a Part D late enrollment penalty later. Check what the new plan covers before you switch.

What a Low Rating Means

Low stars are a warning sign worth reading about, not an automatic reason to panic. Two facts help put a rating in context:

If your plan has been rated below 3 stars for the last 3 years, Medicare gives you a Special Enrollment Period to switch to a different plan at any time while you're in that plan.
Most people are in higher-rated plans. For 2026, about 40% of Medicare Advantage drug plan contracts earned 4 stars or more — and about 64% of enrollees are in those higher-rated contracts.

How to Use Star Ratings When Comparing Plans

Stars are one useful signal — but only one. A high-rated plan still may not cover your doctors or your prescriptions. When you compare plans, look at the stars alongside:

Whether your doctors and hospital are in the plan's network.
Whether your prescriptions are on the plan's drug list, and at what cost.
The plan's premium, copays, and yearly out-of-pocket maximum — see Understanding Your Costs.
How the plan type fits your life — see Choosing Coverage and Medicare Advantage.

MediPrimer doesn't recommend plans. For free, one-on-one help weighing your options, a SHIP counselor can walk through the ratings and your specific needs with you.

Medicaid Star Ratings and Other Ratings You May See

People often search for "Medicaid star ratings" or just "star ratings." A few things to know so you compare the right numbers:

Medicaid plans: the Medicare star ratings on this page do not cover Medicaid plans. Medicaid is run by each state, so plan quality information comes from your state, not from Medicare.gov's Plan Finder. Ask your state Medicaid agency what quality information it publishes for its plans. If you have both Medicare and Medicaid, your Medicare Advantage or D-SNP plan does get a Medicare star rating.
Nursing homes: CMS also runs a separate Five-Star Quality Rating System for nursing homes. On the Nursing Home Care Compare website, each nursing home gets a rating between 1 and 5 stars to help people, families, and caregivers compare homes and spot areas to ask about. CMS says to use the stars together with other information, including a visit to the nursing home and local groups such as the State Ombudsman program.
Plan stars vs. provider stars: a plan's star rating grades the insurance plan. A nursing home's star rating grades the facility. They use different measures and are not comparable to each other.

Common Questions

What is a star rating, in one sentence?

It's Medicare's yearly 1-to-5 quality score for a Medicare Advantage or Part D plan, with 5 stars being the best.

Are there Medicaid star ratings?

Not on Medicare.gov. Medicare's star ratings cover Medicare Advantage and Part D plans only. For Medicaid plan quality, contact your state Medicaid agency, since each state runs its own program.

Does Original Medicare have a star rating?

No. Star ratings score Medicare Advantage plans and Part D drug plans — the private plans you choose among. Original Medicare is the government program itself and isn't rated.

Do star ratings change every year?

Yes. CMS re-scores every plan each year and publishes new ratings each fall on Medicare.gov's Plan Finder. Changes from year to year are normal.

Can I switch to a 5-star plan right now?

If a 5-star plan is available in your area, yes — there's a one-time Special Enrollment Period you can use between December 8 and November 30 of the following year. Watch the drug-coverage trap described above, and see Enrollment & Deadlines for how enrollment windows work.

Does a higher star rating mean a cheaper plan?

No. The stars measure quality of care and service, not price. Compare each plan's premium, copays, and drug costs separately on Medicare.gov.