Public and Senior Health Programs: Medicare, Medicaid, and the ACA Marketplace
Medicare
Part A covers inpatient hospital, skilled nursing after a qualifying stay, hospice, and some home health, and is premium-free with 40 quarters of work history. Part B covers physician and outpatient services with an income-related premium (IRMAA). Part C is Medicare Advantage, which must provide at least the Part A/B benefit package. Part D covers outpatient drugs through private plans. Know the enrollment windows (Initial Enrollment Period, General Enrollment Period, Special Enrollment Period), the Part B late-enrollment penalty (10% of the standard premium for each 12-month period of delay, generally lasting for life), and the Part D late penalty (1% of the national base beneficiary premium per uncovered month). Medigap supplements original Medicare with a six-month guaranteed-issue open enrollment; it does not include drug coverage.
Medicaid and CHIP
Medicaid is a federal-state partnership with state-set eligibility and benefits, covering long-term services and supports that Medicare largely excludes. Dual eligibles qualify for both programs. CHIP covers children in families above Medicaid thresholds.
ACA marketplace
Marketplace plans are metal-tiered (bronze through platinum) with essential health benefits, guaranteed issue, and community rating. Premium tax credits are based on household income relative to the federal poverty level and the benchmark silver plan; cost-sharing reductions attach to silver plans for eligible enrollees.
Traps
Assuming Medicare pays for custodial long-term care, that Medigap covers drugs, or that Part A always carries a premium.
Worked example
Delaying Part B by 26 months triggers 10% x 2 = 20% added to the standard premium, generally for as long as Part B is held.