Medicare Star Ratings Explained
Every October, CMS publishes 1–5 star ratings for every Medicare Advantage and Part D drug plan. These ratings drive plan bonuses, member special enrollment rights, and — for beneficiaries — quick signal about plan quality without wading through hundreds of pages of plan documents. But star ratings have both real value and important limits. Here's how they actually work.
What a 5-Star Rating Requires
CMS scores plans on ~40+ measures across five main categories:
- • Staying healthy (screenings and vaccines) — flu shots, breast/colon cancer screening, blood pressure checks, diabetes screening, and other preventive care rates
- • Managing chronic conditions — how well members with diabetes, high blood pressure, cholesterol issues, and other conditions have their disease controlled
- • Member experience — CAHPS survey scores, coordination of care ratings, ease of getting appointments and care
- • Member complaints and plan changes — how many complaints per 1,000 members, how many members choose to leave, appeal outcomes
- • Customer service — call center wait times, timely appeals decisions, TTY access for hearing-impaired members
Part D drug plans have a similar scoring system focused on medication adherence, drug pricing accuracy, and member service.
How Ratings Are Calculated
CMS collects data from multiple sources — HEDIS clinical measures reported by plans, CAHPS surveys sent to random members, HOS (Health Outcomes Survey) data, and administrative data on complaints and appeals. Each measure is scored on 1-5 stars, then weighted (some measures count more than others), and combined into an overall plan-level rating.
Higher-weighted measures typically include outcomes like blood pressure control, diabetes A1c management, and follow-up after hospitalization. Process measures (like whether screenings were done) count less than outcome measures. This weighting evolves — CMS revises the star ratings methodology every few years.
Why Ratings Affect Your Wallet
- • 4+ star plans receive quality bonus payments from CMS — worth billions annually across the industry. Plans use these bonuses to fund lower premiums, richer benefits (dental, vision, transportation, over-the-counter allowances), or provider network expansions.
- • 5-star plans get a Special Enrollment Period. You can switch to a 5-star plan once per plan year outside normal enrollment windows (December 8 to November 30). If your area has a 5-star plan, this is a benefit worth knowing about.
- • Low-rated plans face marketing restrictions. Plans below 3 stars for 3 consecutive years can be barred from CMS-sponsored marketing and eventually terminated. Members are auto-notified and moved.
How to Find and Use Ratings
The official source is Medicare.gov Plan Finder. When you compare plans in your zip code, filter by star rating (a common approach: only look at plans rated 4+ stars). Ratings for the coming plan year are published in early October — right before Open Enrollment starts October 15.
Star ratings for prior years are archived — you can see how a plan has performed over time. A plan that's been 4+ stars for five consecutive years is a stronger signal than a plan that just jumped from 3.5 to 4 in one year.
Cautions When Using Star Ratings
- • Ratings are plan-level, not doctor-level. A 5-star plan can still have poor providers in your area, a specific specialty gap, or a bad primary care physician near you. Always check individual doctor reviews and network status separately.
- • Ratings are trailing. The 2026 rating uses data from 2023-2024. Plans can improve or decline in the interim. Sudden management changes, network expansions, or CMS methodology shifts can move ratings faster than the historical data reflects.
- • Some measures reflect population, not plan quality. A plan operating in a high-poverty, high-Medicaid area may score lower on screening completion metrics because of member factors outside plan control. CMS has adjustments for socioeconomic factors, but they're imperfect.
- • The 5-star bar has been rising. In 2023, more plans achieved 5 stars because of favorable adjustments during COVID. In 2024, the bar re-tightened and fewer plans hit 5. Compare within a year, not across years.
- • Star ratings don't measure what may matter most to you — like whether your specific doctors are in-network, whether your prescription drugs are covered, or whether the plan's HMO/PPO structure fits your travel patterns.
National Star Rating Trends
For 2026, the average Medicare Advantage star rating is ~4.0. Roughly 40% of MA plan enrollees are in plans rated 4+ stars. The percentage of plans at 5 stars has fluctuated significantly in recent years as CMS refines the methodology.
States with the highest average star ratings tend to have concentrated markets dominated by strong regional insurers (Wisconsin, Minnesota, Utah, Hawaii). States with more fragmented MA markets or heavier rural populations often average lower (Wyoming, Alaska, North Dakota, Mississippi). Check your state's average on our Medicare state pages.
How to Weigh Stars vs Other Factors
Star ratings should be one input, not the whole decision. Practical priority order when comparing plans:
- 1. Are your doctors and preferred hospitals in-network?
- 2. Are your prescription drugs covered at a tier you can afford?
- 3. Is the estimated total annual cost (premium + copays + drug costs) within budget?
- 4. Star rating (4+ preferred, 3+ minimum for a serious look)
- 5. Extras (dental, vision, hearing, transportation, OTC benefit) if they matter to you
- 6. Consistency — has the plan been solid for multiple years, or is it new to your area?
Common Questions About Star Ratings
Is a 4-star plan good enough, or should I insist on 5?
4-star plans are meaningfully better than average and still qualify for CMS quality bonuses. 5 stars is strong but rare — in some markets, no 5-star plan exists, or the 5-star plan has network limitations that make it worse for you than a 4.5-star plan. Don't chase 5 stars if a 4-star plan covers your doctors and drugs better.
Do star ratings apply to Medigap plans?
No. Medigap (Medicare Supplement) plans are federally standardized — Plan G from any insurer covers exactly the same things as Plan G from another insurer. Compare Medigap by price, insurer financial rating, and customer service reputation, not by star ratings.
Do brokers push me toward high-rated plans?
Not necessarily. Brokers earn commissions from insurers, and commissions vary by plan. A 3.5-star plan that pays a higher commission can be pushed over a 4.5-star plan with lower commissions. That's why we recommend using medicare.gov/plan-compare or free non-commissioned SHIP counselors — not a broker — for the initial comparison.
Can I switch to a 5-star plan mid-year?
Yes, once per plan year. If a 5-star plan is available in your area, you have a special enrollment period (December 8 – November 30 of the following year) to switch to it. This is one of the few times Medicare lets you switch outside the annual windows.
What happens if my plan's rating drops?
A slight drop (e.g., 4 to 3.5 stars) has no immediate impact on you. But if it drops below 3 stars, you'll see CMS-mandated language on plan materials. If your plan is under 3 stars for 3 years, CMS may terminate it — you'd be notified and given a special enrollment period to choose a replacement plan.
Do star ratings tell me about drug coverage quality?
Partially. Part D drug plans and MAPD (Medicare Advantage with Part D) plans get separate ratings for their drug coverage that reflect member adherence, drug price accuracy, and appeals handling. But star ratings don't tell you whether your specific drugs are on the formulary or at what tier. Always run your drugs through Plan Finder before enrolling.
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