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Section 5: ready to enroll 

How to Enroll in a Part D Plan

If you don’t have adequate prescription drug coverage, you’ll need to pick a plan






• 8 steps to sign up for a Part D prescription drug plan

• How to pay for Part D

• Who pays the high-income surcharge?

Medicare doesn’t automatically cover prescription drugs but you have two choices if you don’t have other drug coverage: You can either buy a stand-alone Part D plan if you have original Medicare or you can get health and drug coverage from a private Medicare Advantage plan. 


If you have other prescription drug coverage, such as through an employer or retiree plan, find out if it’s considered to be as good or better than a basic Part D plan, what’s known as creditable coverage. Every September your health plan should send you a notice telling you whether your current coverage is considered creditable.


If you have creditable coverage, you don't need to sign up for Part D. If not, you’ll need to find a plan or face a late enrollment penalty that will be added to your Part D premium every month.


If you don’t have creditable prescription drug coverage, the best time to sign up for a Part D plan is during the seven-month initial enrollment period surrounding your 65th birthday — even if you don’t take daily medications now. If you decide to enroll in an economical plan to avoid penalties, you can change your coverage during Medicare’s annual open enrollment period from Oct. 15 to Dec. 7. Coverage starts Jan. 1.




1. Compare Part D options in your area by using the Plan Finder tool at (You can also use the Plan Finder to compare Medicare Advantage plans, which is covered in the previous chapter.)


a screenshot of the main page of the find a medicare plan website with "continue without logging in" circled in red

 You can either log into your online Medicare account or go to the Continue without logging in box where you can enter your ZIP code and select your county. Then choose Drug plan (Part D) from the plan type dropdown menu.

3. Now indicate whether you get help with your medical expenses. If you’re not sure, you can find out by logging in to your Medicare account.

3. Now indicate whether you get help with your medical expenses. If you’re not sure, you can find out by logging in to your Medicare account.

If you don’t receive help, you’ll be asked if you want to see your drug costs when you compare plans. Click Yes so you can get a sense of how much you would spend with each plan.


5. Enter the names of your medications. Be sure to include ones you take regularly to get a good estimate of ongoing costs. You’ll also need to select the dosage and quantity and indicate how frequently you need to refill your prescriptions. To add another medication, click Add Another Drug. When you’re finished, click Done Adding Drugs.

screenshot of the medicare dot gov website showing the field where you can add you prescription drug information

Choose up to five pharmacies to fill your prescriptions. Many plans charge lower copayments for preferred pharmacies. You can see how plans work with pharmacies and what your copayments would be for each one. Enter the names of the pharmacies you use or search by your address or ZIP code.

Every plan with drug coverage offers mail-order prescriptions. They can be less expensive, so some people select this option as one of their pharmacy choices. When you’re finished selecting pharmacies, click Done.

7. You’ll receive a list of drug plans in your area. You can sort the plans in three ways: Lowest drug + premium cost, the default; Lowest yearly drug deductible; and Lowest monthly premium. The best way to compare plans is to look at each plan’s lowest drug and premium costs.

a screenshot of the medicare plan finder tool local drug plan results page. The field to sort plans by lowest drug and premium cost is circled in red.

Keep in mind: A plan with a low premium could be more expensive by the end of the year if it charges high copayments for your medications. Click Plan Details for more information, including a monthly estimate of what you’ll pay for your medications.

If you're interested in a plan, before signing up, be sure to check whether your prescriptions are part of a plan’s formulary — the list of regularly covered drugs — and whether it has prior authorization requirements or other restrictions. 

a screenshot of the medicare plan finder tool local drug plan results page with a blue plan details button circled in red

8. To sign up for a Part D plan, click Enroll. You’ll need your Medicare number and the date that your Parts A and B coverage started. To enroll, call 800-MEDICARE (800-633-4227).

To sign up directly through a private insurer, click Plan Details and look for the plan's phone number and website.  You can also request an application and mail it. An insurance agent may be able to help you enroll.


For help signing up for a Part D plan, contact your State Health Insurance Assistance Program (SHIP).



After you’ve signed up, you’ll pay monthly Part D premiums to the insurance company, either billed or through automatic payments. You can request that your premium be deducted from your monthly Social Security or Railroad Retirement Board payment.

To find out if you qualify for financial assistance for Part D, see How to Get Help Paying for Medicare.


If your modified adjusted gross income is more than $103,000 if you’re single, or $206,000 if you’re married and filing jointly, you may face a high-income surcharge, which adds from $12.90 up to $81.00 to your monthly premiums in 2024.


The high-income surcharge is paid to Medicare. These premiums can be deducted automatically from your Social Security benefits or Medicare can send you a bill. Another option is to sign up for Easy Pay and have the premiums automatically paid from your checking or savings account.

Mark your calendar for Medicare’s annual open enrollment period from Oct. 15 to Dec. 7. This is the time you can switch Part D plans.

Even if you’re satisfied with your coverage, it’s a good idea to go to to compare the plans available in your area. Plans can change their coverage, costs and provider networks every year.

Updated March 27, 2024



How to Enroll in a Medicare Advantage Plan
How to Buy a Medigap Policy