Millions of seniors rely on Medicare to cover their health-related needs. But Medicare isn't a one-size-fits-all solution. In fact, the program has several distinct parts that enrollees can sign up for or opt out of.

Those who enroll in original Medicare will generally get free coverage under Part A, which pays for hospital visits. They'll then pay a monthly premium for Part B, which covers preventive care and diagnostics, as well as Part D, which covers prescription drugs. But there's an alternative to Medicare that many seniors choose instead, and it's Part C, otherwise known as Medicare Advantage.

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Medicare Advantage essentially bundles all your coverage needs, including prescriptions, into a single plan. The premium you pay for your plan will depend on the level of coverage you choose. But often, Advantage plans end up coming in cheaper than original Medicare, all the while offering at least the same level of coverage, if not more.

In fact, many seniors choose Advantage over traditional Medicare because the former covers dental, hearing, and vision -- services original Medicare does not pay for. Many Advantage plans also offer coverage overseas, which is helpful for seniors who travel often. Furthermore, changes to Medicare Advantage set to take place in 2019 make it an even more attractive option. Here are three you should know about:

1. Lifestyle support

As we age, our mobility tends to decline. But effective January 2019, Medicare Advantage plans will have the option to cover things like transportation to and from medical appointments and meal delivery to seniors' homes. Similarly, Medicare Advantage will soon be able to offer enrollees coverage for home safety features like wheelchair ramps and bathtub/shower support bars. These benefits can no doubt lower seniors' chance of injury, so if you're experiencing mobility issues, it pays to see how an Advantage plan might help alleviate some of them.

2. Daily living help

Many seniors struggle to do things like bathe and get dressed, yet want to continue living independently. Soon, Medicare Advantage will be able to offer health-aide coverage for folks who need help with personal care at home, as well as things like cooking, cleaning, and errands.

3. The ability to try out a plan before you commit

The last thing you want is to sign up for a health plan only to find that it doesn't meet your needs. Going forward, you'll have the option to try out a Medicare Advantage plan for up to three months and switch back to a different plan (either another Advantage plan or original Medicare) if you're not happy. This, in turn, takes some of the stress out of choosing a plan.

There are plenty of good reasons to sign up for a Medicare Advantage plan for 2019, and starting next year, a new open enrollment period for Advantage will kick off on Jan. 1 and run all the way through March 31. If you're already enrolled in Medicare Advantage, you'll have the option at that time to move from one Advantage plan to another. Otherwise, you can sign up for Medicare Advantage during the general Medicare open enrollment period, which runs from Oct. 15 through Dec. 7.

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