By the end of 2021, nearly 64 million people were enrolled. Medicare consists of hospital insurance (Part A), medical insurance (Part B), and drug coverage (Part D), plus Medicare Advantage plans and Medigap policies.

When Is Medicare Open Enrollment?

Medicare open enrollment is from Oct. 15 to Dec. 7 each year. Your new coverage will begin Jan. 1 of the following year if you enroll by the deadline. There are designated “open enrollment” periods for Medicare Advantage and Medigap plans in addition to the regular Medicare open enrollment period.

Medicare Advantage Open Enrollment

Medicare Advantage, also called Part C, is another way to get your Original Medicare (Parts A and B) and Part D benefits. These plans are offered by private insurers and provide your Part A and Part B coverages, often with enhanced benefits. Plans typically include drug coverage, as well.  You can make changes to your existing Medicare Advantage plan during both the Medicare open enrollment period and the Medicare Advantage open enrollment period. You can switch to a new Medicare Advantage plan or drop it and switch to Original Medicare. The Medicare Advantage open enrollment period is from Jan. 1 to March 31 each year. Your new coverage will start on the first day of the month after the new plan receives your enrollment request.

Medigap Open Enrollment

Medigap, also known as Medicare supplement insurance, is an optional coverage that supplements your Part A and Part B coverage. It’s sold by private insurance companies and can help cover copayments, coinsurance, deductibles, and other benefits. The Medigap open enrollment period begins the first day of the month in which you turn 65 and are enrolled in Medicare Part B. It lasts for six months. This is the best time to enroll in a Medigap plan because insurers are not allowed to consider any preexisting conditions you may have when pricing your plan, nor can they refuse to cover you because of preexisting conditions. You’re not guaranteed a plan and you could pay more for it if you don’t get coverage during this time. Coverage for your Medigap plan generally starts the first day of the month after you apply.

The Purpose of Medicare Open Enrollment

There are multiple enrollment periods for Medicare, including initial enrollment, special enrollment, general enrollment, and open enrollment. What you can do during these periods differs and may depend on what plans you’re already enrolled in. Open enrollment is important because it’s the time of year during which you can make certain changes to your existing coverage, whether you have Parts A and/or B or if you also have a Medicare Advantage plan. You can also switch to another Part D prescription drug plan, or you can add a plan if you didn’t enroll in Part D when you were first eligible.

What You Can Do During Open Enrollment

You can add or drop a Part D prescription drug plan If you’re already enrolled in Medicare Part A or Part B. You can also choose a different Part D drug plan if you’re unhappy with your current one. You can switch from Original Medicare (Parts A and B) to a Medicare Advantage plan. You can choose a plan that better suits your needs if you currently have a Medicare Advantage plan. You can switch to another Medicare Advantage plan without drug coverage, and vice versa. You can also switch to Original Medicare if you prefer. But you may not be able to get a Medigap policy if you go back to Original Medicare, and you may want to separately purchase Part D drug coverage. Visit Medicare.gov to compare plans against your current plan for coverage, price, providers, and other benefits.

What You Can’t Do During Open Enrollment

You can’t enroll in Parts A or B, and you can’t enroll in a Medicare Advantage plan if you don’t already have Original Medicare. You also can’t enroll in a Medigap plan. The best time to enroll in Parts A and B is often during your initial enrollment period or, for Medigap, during the Medigap open enrollment period. You can enroll in Parts A, B, and D or a Medicare Advantage plan during the general enrollment period (Jan. 1 to March 31, each year) if you miss your initial enrollment period. In 2022, your coverage would start July 1; beginning in 2023, it would start the month after you signed up.

What If You Miss Open Enrollment?

If you miss the open enrollment period and want to make changes to your policy, you’re in luck if you have a Medicare Advantage plan. The Medicare Advantage open enrollment period begins shortly after the regular open enrollment period closes. So you’ll get another chance from Jan. 1 to March 31 to switch or drop your Medicare Advantage plan if you miss the Dec. 7 deadline. But you’ll have to wait until the next open enrollment or until a special enrollment period to make changes to your plan if you have Original Medicare and miss open enrollment.