With open enrollment for Medicare starting in October, it's important to understand how Medicare Advantage plans will be different next year and how your expenses -- and treatment options -- may change. A thorough understanding of how your chosen plan works will help you minimize your healthcare expenses for the year.

Changes to existing plans

Before you decide to stick to the same plan you had in 2017, review it carefully to see if anything important has changed. The most common changes to Medicare Advantage plans include prescription formularies (the list of drugs that the plan covers and how much it charges for them), premiums (how much you pay for the plan each month), and cost-sharing (the percentage or dollar amount that the plan pays toward your medical expenses as you incur them).

Senior couple using a laptop

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Changes to network coverage

Plans may also change their network coverage from year to year, so check to make sure that your primary care physician is still included in the plan's network. In rural areas, it's particularly important to confirm that the network you choose includes a wide range of specialists in your general vicinity. And if you decide to switch to a new Medicare Advantage plan for 2018, definitely check the provider network before making any decisions.

If provider networks in your area are particularly spotty for 2018, consider switching to a non-network type of Medicare Advantage plan such as a Private Fee-for-Service (PFFS) plan or a PPO. With PPOs, you can use out-of-network providers but will generally pay more to do so. PFFS plans may or may not have a network; the ones that do have networks generally also charge you more to use out-of-network providers.

Loss of insurers

While the loss of insurers in Obamacare programs is fairly well-known, the poor insurance coverage of Medicare Advantage in some areas is not. As of 2017, 147 different counties have no Medicare Advantage insurers at all. The affected counties are chiefly in rural areas and are spread across 14 different states. Whether this situation will be better or worse in 2018 remains to be seen, but it's definitely a concern -- especially if you live in a rural county.

Should you discover that there are no Medicare Advantage plans in your area that meet your needs, consider switching to a Medigap plan. Medigap is paired with original Medicare (Medicare Part A and Part B) and covers many healthcare expenses that aren't included in those parts of Medicare, so these plans can serve as an excellent substitute for Medicare Advantage.

Loss of State Health Insurance Assistance Programs (SHIPs)

The State Health Insurance Assistance Programs provide free Medicare counseling and assistance in every state. This counseling can be particularly useful when trying to decide which Medicare plan to choose for the year. However, President Trump's proposed budget eliminates 94% of SHIP's funding, which would significantly reduce the program next year.

Since this may be the last year that SHIP counseling is widely available, you might as well take advantage of it while choosing your Medicare Advantage plan for next year. You can find the SHIP web address and phone number for your state on the Seniors Resource Guide website.