Medicare Advantage (Part C) plans are provided by Private insurance companies. These plans replace the coverage provided by Original Medicare (Part A & B) with many additional benefits. Advantage plans are highly regulated to be actuarially equivalent to Original Medicare, but there are tradeoffs. With Original Medicare, you have total control of your healthcare and total freedom to go to almost all doctors or hospitals in the U.S., but you also have a Part A deductible and Part B 20% coinsurance (that has no ceiling). With Medicare Advantage, these are replaced with small copays and you have a maximum out of pocket to serve as a stop gap.

Medicare Advantage include a regional network of providers (e.g. HMO or PPO plans). Depending on where you live, many plans include additional benefits not part of Original Medicare.