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Medicare provides useful healthcare coverage for eligible retirees, but it doesn't cover everything. In order to get more complete coverage, many people look to Medicare Advantage. Also known as Medicare Part C, Medicare Advantage features private insurance companies that provide the same services that original Medicare does, along with certain supplemental coverage options that fill in some of the gaps of Medicare coverage. In order to take full advantage of Medicare Advantage, however, it's important to know what options you have. Below, we'll look at three common moves involving Medicare Advantage that you can use to your benefit.

1. Choosing Medicare Advantage when you initially enroll for Medicare.

Medicare Advantage is available to anyone who's eligible for Medicare. That includes those who are still in their initial enrollment period, which begins for most people three months before turning 65 and extends three months past their 65th birthday.

In assessing whether choosing a Medicare Advantage plan is a smart move, it's important to understand how it differs from traditional Medicare coverage. Original Medicare allows you to use any doctor or healthcare provider you choose as long as they're part of the Medicare program. By contrast, Medicare Advantage plans usually come in the form of a health maintenance organizations or preferred provider organization, where you only get the lowest costs if you use hospitals, doctors, and other healthcare service providers that have agreements with the plan provider.

In addition, coverage and costs can vary. Medicare Advantage often includes types of coverage that original Medicare doesn't provide, including out-of-pocket maximums on an annual basis. However, in addition to the typical Part B premium amount, Medicare Advantage participants usually pay an extra monthly premium amount. In considering a plan, it's important to get all the information on coverage and cost, and that will help you decide whether a Medicare Advantage plan will be less expensive than original Medicare in your particular situation.

2. Switching to Medicare Advantage from original Medicare.

Many Medicare participants never change whatever initial decision they make, sticking with their past selections year after year. Yet every year, Medicare gives you a chance to switch to or from Medicare Advantage plans, and that makes it worth a closer look on an annual basis in order to make sure you're making the most of your coverage.

In particular, the Medicare open enrollment period from Oct. 15 to Dec. 7 gives you a chance to change from original Medicare to a Medicare Advantage plan or vice versa. In some cases, it can be smart to start with original Medicare in one year but switch to Medicare Advantage later on. For instance, if you're relatively healthy and don't need many services, then the less comprehensive coverage of original Medicare might meet your needs. Later on, though, if you need more healthcare services, having benefits like an out-of-pocket maximum can make Medicare Advantage more cost-effective.

3. Switching between Medicare Advantage plans.

In addition to moving between original Medicare and Medicare Advantage, you can also use the annual open enrollment period to switch between two different Medicare Advantage plans. That can be valuable, because different plans cover different things.

For instance, one common switch involves trading a plan that doesn't include prescription drug coverage for one that does include drug coverage. You have the option with Medicare Advantage to sign up with a separate prescription drug coverage provider under Medicare Part D, but many participants find it more useful to integrate their drug benefits with the rest of their Medicare Advantage benefits. If your needs for prescription drugs change dramatically between one year and the next, then an appropriate switch in one direction or the other can make a big difference in your out-of-pocket costs when you consider both the premium payments you'll owe and the copayments and other costs of prescription drugs under the plan.

Medicare Advantage plans have become more popular in recent years, and the flexibility they provide is one reason why more Medicare participants choose the plans. By knowing your options with Medicare Advantage plans, you can ensure that you won't miss out on the opportunities that the plans provide to help you manage and minimize your healthcare costs in retirement.