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Medicare Advantage
Part C plans replace Original Medicare with a private, network-based bundle. Often $0 premium; trade-off is prior authorization and narrower networks.
Enrollment share: 54%
EnrollmentAEP Oct 15 – Dec 7MA Open Enrollment Jan 1 – Mar 31Part B Standard Premium $185.00/moPart A Deductible $1,676Medicare Beneficiaries 68.4M
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Medigap
Supplemental policies that pay Original Medicare's cost-sharing. Plan G and Plan N dominate new enrollment; underwriting rules vary by state.
Plan G avg. premium: $155/mo
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Part D
Prescription drug coverage sold through standalone PDPs or bundled into MA plans. 2025 introduced a $2,000 out-of-pocket cap.
OOP cap 2025: $2,000
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Enrollment
Initial Enrollment Period, Annual Election Period, MA Open Enrollment, Special Election Periods — miss a window and penalties follow you for life.
Part B late fee: 10% / yr
In Depth · Carrier Reviews
The Ten National Medicare Advantage Carriers, Ranked
Scored on CMS Star Rating, prior-authorization denial rate, in-network provider breadth, drug formulary generosity, and appeal-overturn rates reported to CMS.
| Rank | Carrier | Star Rating | PA Denial | Overturn on Appeal | Grade |
|---|---|---|---|---|---|
| 1 | Kaiser Permanente | 4.5 | 4.8% | 82% | A |
| 2 | Humana | 4.0 | 6.9% | 78% | A− |
| 3 | UnitedHealthcare | 4.0 | 9.1% | 76% | B+ |
| 4 | Aetna (CVS Health) | 3.5 | 8.6% | 72% | B |
| 5 | Cigna Healthcare | 3.5 | 7.4% | 74% | B |
| 6 | Blue Cross Blue Shield | 3.5 | 8.2% | 70% | B |
| 7 | Elevance (Anthem) | 3.5 | 10.4% | 68% | B− |
| 8 | Centene (WellCare) | 3.0 | 12.6% | 64% | C+ |
| 9 | Molina Healthcare | 3.0 | 13.1% | 61% | C |
| 10 | Devoted Health | 3.5 | 9.8% | 69% | B− |