Two key Medicare enrollment deadlines are approaching. Here’s what you should know

A couple of Medicare enrollment periods are underway — and both end soon.

First, if you didn’t enroll in Medicare when you should have and you don’t qualify for a special enrollment period, you can sign up until March 31. Second, if you are already on Medicare and use an Advantage Plan but don’t think it’s a good match for you — i.e., your doctor is out of network — you can switch to another plan or drop it altogether, also until the end of the month.

However, each of these opportunities comes with different rules to be aware of, and, possibly, the need to enroll in additional coverage and deal with other deadlines as well. Also, if you miss one of these periods but should have used it, you generally would have to wait for another enrollment window that allows you to get or change coverage.

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Here’s what to know.

You become eligible for Medicare at age 65, and you get a seven-month window to sign up. This initial enrollment period starts three months before your birthday month and ends three months after it.

If you missed that window and didn’t have qualifying coverage elsewhere — such as a plan through a large employer — you can sign up for Part A (hospital coverage) and/or Part B (outpatient care coverage) between Jan. 1 and March 31. Signing up during this so-called general enrollment period means coverage starts the month after you enroll; before 2023, the effective date was July 1.

Be aware that depending on how long you’ve gone without Part B coverage, you may face a late-enrollment penalty of 10% for each year you should have been signed up but weren’t. And that penalty, which is tacked on to your premium, is lifelong. 

You also can sign up for an Advantage Plan (Part C) once you’ve applied for Parts A and B during this general enrollment period, but it must be done before your Part B coverage starts. The Advantage Plan may or may not include Part D prescription drug coverage, but most do.

However, if you want a standalone Part D plan to pair with Parts A and B, this general enrollment period is not for that.

“They should consult an agent to see if they qualify for a special enrollment period for Part D, such as losing other creditable coverage in the last 63 days,” said Danielle Roberts, co-founder of insurance firm Boomer Benefits.

If you don’t qualify for a special enrollment period or an exception, you’d generally have to wait until Medicare’s fall annual enrollment period to sign up for a Part D plan.

“If there isn’t a valid special enrollment period that a broker can help you with, it’s still worth a call to 1-800-MEDICARE as they have broader ability to approve unusual special enrollment periods,” Roberts said.

Be aware that Part D also comes with a lifelong late enrollment penalty if you go without qualifying coverage for 63 days or more. That fee is 1% of the national base premium ($32.74 in 2023) for each full month you didn’t have Part D or other acceptable coverage.

Also, individuals who use the general enrollment period can sign up for a Medicare supplemental plan, or “Medigap.”

“The Part B effective date would also initiate a six-month Medigap open enrollment period, if they’d rather go that route,” Roberts said.

Separately, but also between Jan. 1 and March 31, Medicare allows Advantage Plan enrollees to switch to another plan or drop it altogether in favor of basic Medicare (Parts A and B). 

Unlike during the annual fall enrollment period when you can change your mind multiple times about your coverage for the following year, you can only make one switch during the current window.

“So if you choose another Medicare Advantage Plan, choose carefully,” Roberts said, adding that you’ll be locked into that coverage choice for the rest of 2023.

If you want to return to basic Medicare instead of having an Advantage Plan, be aware that the move often means losing drug coverage — which means you would have to enroll in a standalone Part D plan.

Additionally, if you drop your Advantage Plan, don’t assume that you’ll be able to get a so-called Medigap policy, which many beneficiaries pair with basic Medicare. These plans either fully or partially cover cost-sharing of some aspects of Parts A and B, including deductibles, copays and coinsurance.

However, they come with their own rules for enrolling. So depending on your state, you may need to pass medical underwriting to get approved for a Medigap policy.

There is an exception to the medical underwriting requirement: If you are within the first year of trying out an Advantage Plan, you generally can return to a Medigap policy without facing underwriting.