Part A42 U.S.C. § 1395d
Hospital insurance benefits
Part A law identifies major categories of hospital, skilled nursing, home health, and hospice benefits. Coverage conditions and benefit periods still apply.
Official excerpt (English)“inpatient hospital services, post-hospital extended care services, home health services, and hospice care”
Read official source ↗Part B42 U.S.C. § 1395k
Supplementary medical insurance
Part B is the medical-insurance side of Original Medicare. Detailed definitions, exclusions, medical necessity, and cost sharing determine what is payable.
Official excerpt (English)“medical and other health services”
Read official source ↗Part C42 U.S.C. § 1395w–21
Medicare Advantage eligibility and election
The statute ties Medicare Advantage eligibility to Part A entitlement and Part B enrollment, then sets election and enrollment rules.
Official excerpt (English)“entitled to benefits under part A and enrolled under part B”
Read official source ↗Part D42 U.S.C. § 1395w–101
Prescription drug plan enrollment
This section establishes how an eligible person may obtain Part D prescription drug coverage, including coordination with Medicare Advantage choices.
Official excerpt (English)“may obtain qualified prescription drug coverage through enrollment in a prescription drug plan”
Read official source ↗Plan rights42 C.F.R. § 422.111
Medicare Advantage disclosures
Medicare Advantage organizations must explain benefits, costs, networks, prior authorization, appeals, and other plan information in the CMS-prescribed manner.
Official excerpt (English)“Prior authorization rules and other review requirements that must be met in order to ensure payment for the services.”
Read official source ↗Drug-plan rights42 C.F.R. § 423.128
Part D plan information
Part D sponsors must provide plan details including formulary operation, exception procedures, cost sharing, pharmacy access, and appeal rights.
Official excerpt (English)“the process for obtaining an exception to a plan’s formulary or tiered cost-sharing structure”
Read official source ↗