I have original Medicare. Do I need Part D too?

Part D prescription drug coverage is a voluntary benefit; you’re not obliged to sign up. You may not need it if you have drug coverage from elsewhere that’s “creditable” — meaning Medicare considers it to be of the same or better value than Part D. This coverage could come from an employer or union, retiree benefits, COBRA, Tricare or the Veterans Affairs health program.

If you don’t have creditable coverage, you must sign up for a Part D plan within certain time frames after enrolling in Medicare Part A or B to avoid a late enrollment penalty. The penalty lasts for as long as you have Part D coverage.

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How do I know if I have creditable coverage?

If you’re eligible for Medicare and have prescription drug coverage from a source other than Medicare, the plan must send you a notice each September letting you know if your drug coverage is creditable. Plans can change their coverage from year to year; just because it may be deemed creditable one year doesn’t guarantee that it will be the following year. Keep a copy of the notice as proof of creditable coverage when you enroll in Part D.

If you lose creditable drug coverage, you typically have a two-month special enrollment period to join a Part D plan. If you don’t sign up during that time, you may have to pay a late enrollment penalty.

How can I get Part D coverage?

Original Medicare doesn’t cover prescription drugs, but there are two ways to get Part D coverage.

If you have either Medicare Part A and/or Part B, you can get a stand-alone Part D plan from a private insurer. In 2024, depending on your state, you may have from 15 to 24 stand-alone Part D plans to choose from, according to KFF. The costs of coverage — premiums, deductibles and copays — vary according to the drug plan you choose. You can use the Medicare Plan Finder to compare total costs, including premiums plus copayments for your drugs, under each Part D plan available in your area.

Another option is to sign up for a Medicare Advantage plan with prescription drug coverage. These private plans cover both health care and prescription drugs but must be approved by Medicare. MA plans use provider networks, and you may have to pay more or forgo coverage if you choose to use a doctor or service not in the plan’s network.

In 2024, the average Medicare beneficiary has 43 Medicare Advantage plans to choose from, reports KFF. To qualify for a Medicare Advantage plan, you must have both Part A and Part B. You have to pay premiums for Part B (and Part A if you’re not eligible for premium-free Part A); more than half of Medicare Advantage plans don’t charge additional premiums. Expect to pay copayments for your medications too. 

You can use the Medicare Plan Finder to see how much you’ll pay for your prescription drugs under MA plans available in your area. You can also compare copayments and out-of-pocket costs for care.

Do I need Part D if I don’t take any prescription drugs?

Yes. You may have a late enrollment penalty if you don’t sign up for Part D or a Medicare Advantage plan with drug coverage within a certain time frame, even if you aren’t on any medication.

It’s important to understand that Part D is insurance. Just like any other insurance, you buy a Part D plan to cover prescription costs you may need now or in the future. But also like other insurance, you can’t postpone enrollment until there’s a need for coverage, such as prescribed medication to treat a medical condition or injury. You can sign up or switch Part D plans only during designated enrollment periods.

Keep in Mind

If you aren’t on prescription medication, one way to avoid the late enrollment penalty is to sign up for a Part D plan with low premiums. If you’re prescribed drugs with high copayments during the year, know that you have an opportunity to switch plans during open enrollment, which runs from Oct. 15 to Dec. 7 for coverage starting Jan. 1.

If you need financial help with the premiums and out-of-pocket costs, you may be eligible for the Extra Help program.

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