While the main open enrollment period for Medicare takes place from mid-October to early December every year, there's another open enrollment period for people signing up for Medicare Advantage plans that runs from Jan. 1 to March 31 this year.

Medicare Advantage plans, sometimes referred to as Plan C, are popular with consumers because they are comprehensive, offer low premium costs, and appear simpler than original Medicare. Some Advantage plans don't even charge premiums. Many also have out-of-pocket limits, which lets healthcare consumers manage expected costs for the year. They are mandated to offer at least as much coverage as Medicare Part A (hospital insurance) and Part B (medical and physician insurance) provide. Many Medicare Advantage plans offer more, such as prescription coverage and options for dental, vision, and hearing coverage.

Senior man talking to doctor.

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Medicare Advantage plans can change

Medicare Advantage plans can change year to year, both in coverage and in cost.

Offered by private insurers such as Blue Cross/Blue Shield and Aetna, these plans are regulated by the U.S. government. While they are required to meet the coverage that original Medicare offers in its Part A and Part B, other aspects of Medicare Advantage plans vary.

For instance, prescription drugs can fall off your insurance policy's formulary (meaning that the Medicare Advantage plan will no longer pay for it). Perhaps part of the coverage you've enjoyed, such as vision or dental, are reduced or dropped all together. Providers who were once in-network can move out-of-network and if you keep seeing them, you could be on the hook for the whole cost of your visit and all services you receive.

Review your Plan C every year

For this reason, if you're covered under a Medicare Advantage plan, it's extremely important to review your costs and coverage every year. Health care is crucial for senior citizens, and its costs are rising steeply. The second enrollment period is a good time to sit down, roll up your sleeves, and consider whether your plan still meets your needs.

First, review your coverage. Read the fine print. Look over your medical treatment for the past year. Did your health or needs change in a way that means you need something new in 2019 that you didn't require in 2018? If you develeoped vision issues, vision insurance might be important for you to add on. Were you prescribed new medication? Then you need to make sure it's on formulary for your plan, or you'll be paying for it all out of pocket. Are you happy with the providers in your network?

Next, review your costs. There's no substitute for number crunching, so grab a pencil and paper. Medicare Advantage plans can seem like the lower cost option because premiums are often low. But it's critical to know that premiums do not constitute all the costs of any insurance plan. You must total up what you will pay for co-pays and out-of-pocket expenses. Do they seem reasonable, or are they higher?

Third, review your plan to make sure it still covers everything it did last year because it's not guaranteed to stay the same. If you like your doctor and local hospital, make sure they are still in-network. Check to see your prescription drugs are still on formulary.

If you find areas of your Medicare Advantage plan you'd like to change, here are two things to know about the second open enrollment period.

1. You can switch from one Medicare Advantage plan to another

If your current Medicare Advantage plan no longer suits your needs or your budget, you can change to another one during the open enrollment period from Jan. 1 to March 31 period. Review the coverage and costs on other plans offered in your area here. The Medicare system also offers a starred rating system for Medicare Advantage plans, so it would be beneficial to look at the ratings as well. 

2. You can switch to original Medicare

If there isn't a Medicare Advantage plan to your liking, or you decide original Medicare is more advantageous, you can switch to original Medicare at this time. (If you're currently in original Medicare, the second enrollment period isn't for you and you'll need to wait to change your plan until the first open enrollment period, from October to early December.)

Participants in original Medicare Plan A and Plan B pay premiums, co-pays, and out-of-pocket expenses. If you choose prescription drug coverage in original Medicare, Plan D, you will pay all these costs for Plan D as well.Despite higher costs than some Medicare Advantage plans, original Medicare may suit your needs better. Provider coverage may also be more ample. With an original Medicare card, you can go to any medical professional or hospital or clinic that accepts it, while Medicare Advantage plans may have limited in-network options.

The current enrollment period is a chance to tune up your healthcare plan to make sure it fits your current situation.