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Come to Nevada for the roulette tables. Stay for the affordable retiree health insurance. That's because the Silver State is home to the lowest Medicare Advantage costs for the 2019 plan year, according to an analysis by HealthMarkets Insurance Agency. The firm studied cost data from the Centers for Medicare & Medicaid Services. You might know "original Medicare." It consists of two parts: Part A covers care received in a hospital and Part B covers doctors' services and medical supplies. Medicare Advantage or Part C, is a private plan that provides Part A and Part B benefits, and often prescription drug coverage as well. See below for the top 10 states with the lowest Medicare Advantage annual costs, according to HealthMarkets.

During open enrollment season — Oct. 15 through Dec. 7 — enrollees can swap from Medicare Advantage to original Medicare. They can also trade from original Medicare to Medicare Advantage or go from one Medicare Advantage to another. Things are about to get a little cheaper year-over-year for Medicare Advantage enrollees. "On a total cost basis, which includes max out-of-pocket expenses, deductibles and premiums nationwide, it's down about 3 percent," said Michael Z. Stahl, chief marketing officer at HealthMarkets. Here's what you need to know.

Cost drivers

About 19 million people were enrolled in Medicare Advantage plans in 2017, accounting for 33 percent of all Medicare beneficiaries, according to the Kaiser Family Foundation.

In particular, Medicare Advantage annual premiums year-over-year are down by about $185 on average, nationwide, Stahl said. One reason could be related to a one-year reprieve of a health insurance tax on insurers, created by the Affordable Care Act, and designed to help fund federal and state insurance marketplace exchanges. The levy is expected to cost insurers $16 billion in 2020, once the tax is back in effect, according to Oliver Wyman.

What you should know

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