Medicare Advantage

Before You Compare Plans, Here's What Star Ratings Actually Measure

People in Evanston can choose from 67 Medicare Advantage plans for 2027, against 78 this year. 17 of this year’s plans are gone, 6 are new to Cook County, and 30 that continue have changed their premium, deductible, plan type or name, 9 of them under a new name.

EVANSTON, Ill. — With the Medicare Annual Enrollment Period opening October 15, Evanston residents sorting through mail and TV ads will see one number pop up again and again: a plan's Star Rating. Those ratings, published by the Centers for Medicare & Medicaid Services (CMS) each fall, are meant to give shoppers a quick read on how a Medicare Advantage or Part D plan performed over the past year — but they measure specific things, and it helps to know what before you start comparing.

What Star Ratings actually measure

Star Ratings are CMS's yearly report card on Medicare Advantage and Part D prescription drug plans. Plans are scored on a 1-to-5 scale, with 5 being the highest. The rating is not about how cheap a plan is or how generous the extras look on a flyer — it's about how the plan performed on quality and service measures.

For Medicare Advantage plans that include drug coverage, CMS looks at roughly 40 different measures. Stand-alone Part D plans are graded on a smaller set focused on the drug benefit.

The categories behind the score

CMS groups the measures into a few broad areas:

• Staying healthy: whether members got recommended screenings, vaccines, and check-ups.
• Managing chronic conditions: how well the plan supports people with diabetes, heart disease, and similar conditions.
• Member experience: what enrollees say in surveys about their care and their plan.
• Member complaints and changes in performance: how often people complain or leave the plan, and whether performance is improving.
• Customer service: how the plan handles appeals and calls.
• Drug safety and pricing accuracy: for Part D, things like safe prescribing of certain medications and accurate pricing information.

When the ratings come out

CMS releases the new Star Ratings in October, timed so they are on Medicare.gov's Plan Finder before AEP opens October 15. When you look up plans available in Cook County — which includes Evanston — the star next to each plan reflects the newest round of scores.

Ratings can move up or down from year to year, so a plan's number this fall may not match what it had last fall.

How to use ratings without letting them decide for you

A Star Rating is one useful data point, but it isn't the whole story. Two things worth remembering:

• Ratings measure the plan's past performance overall, not how it will work for your specific doctors, hospitals, or prescriptions.
• A higher-rated plan is not automatically the right fit if your medications aren't covered well or your providers aren't in network.

The best approach is to check the star score, then look at the details that affect you personally — provider networks, drug formularies, and total expected costs — on Medicare.gov or with a trusted counselor.

What else is changing for 2027

While you're reviewing plans this fall, a few program-wide 2027 numbers are worth knowing:

• The Part D out-of-pocket cap is $2,100 in 2026 and $2,400 in 2027.
• The Part D maximum deductible is $615 in 2026 and $700 in 2027.
• The coverage gap ("donut hole") is gone as of 2025, leaving three payment phases.
• The Medicare Prescription Payment Plan lets you spread drug costs across the year in monthly installments.
• IRMAA income surcharges for higher earners start above $109,000 for a single filer.

These figures apply nationwide, including in Evanston.