The Medicare Advantage program - also known as Medicare Part C - offers beneficiaries the option of receiving all of their Medicare benefits from health plans run by private companies.
The cheapest Medicare Advantage plans generally cost zero to around $100 per month. They include pretty much all that's involved in an A plus B plus D plus Medigap custom plan. However, these plans have a managed care system, so you must stay in-network and get referrals to see specialists.
Unlike Medicare Cost Plans, Medicare Advantage plans assume financial risk if payments from Centers for Medicare & Medicaid Services do not cover their costs.
Balance billing is prohibited for Medicare-covered services in the Medicare Advantage program, except in the case of private fee-for-service plans. Fee-for-service plans are more expensive, but allow you to go out of network.
For enrollment periods, see the Medicare Part A page of this guide.