When and where you can sign up for Part D

You sign up for Medicare Part D (prescription drug coverage) through insurance companies, not through Medicare directly. You choose a Part D plan offered by a private insurer, and that company handles your enrollment. The three main times you can sign up without waiting or paying a penalty are: when you first turn 65, during the annual open enrollment period (October 15 to December 7 each year), or if you experience a may have access to life event like losing other drug coverage.

If you miss these windows, you can still sign up, but you may pay a late enrollment penalty — an extra amount added to your premium each month for as long as you have Part D. The penalty is calculated based on how many months you went without coverage, so signing up sooner rather than later costs less over time.

You can enroll online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), or in person at a local Social Security office. Many insurance brokers and counselors also help people choose and enroll in plans at no cost to you.

Key Takeaways

  • You enroll in Part D through private insurance companies, not Medicare itself, by choosing a specific plan that fits your medications and budget.
  • The best time to sign up is when you turn 65, during open enrollment in October through December, or within 63 days of losing other drug coverage.
  • If you sign up late without a may have access to reason, you will pay a monthly penalty on top of your premium for the rest of your coverage.
  • You can enroll online at Medicare.gov, by phone, or with help from a free local counselor who knows your area's plans.
  • Part D plans vary widely in cost and which drugs they cover, so comparing plans before you sign up can save you hundreds of dollars a year.

Steps to compare and choose a Part D plan

Before you sign up, spend time comparing plans because the cost difference between them can be significant. Go to Medicare.gov and use the Plan Finder tool. Enter your medications (the actual drug names and doses you take), your pharmacy, and your zip code. The tool will show you every Part D plan available in your area, ranked by estimated yearly cost for your specific drugs.

As you compare, look at three numbers: the monthly premium (what you pay every month), the deductible (what you pay out of pocket before the plan starts paying), and the copay or coinsurance (what you pay per prescription). A plan with a low premium might have a high deductible, or a plan with no deductible might have higher copays. The Plan Finder estimates your total cost, which helps you see the real picture.

Check whether your pharmacy is in the plan's network. Some plans work with most pharmacies; others have a smaller list. If you use a mail-order pharmacy or a specialty pharmacy for expensive drugs, confirm that the plan covers it. A plan that looks cheap on paper might cost more if your pharmacy is not included.

Understanding the coverage gap and extra help

Part D has a coverage gap, sometimes called the "donut hole." Once you and your plan have spent a certain amount on drugs in a year, you enter the gap and pay more out of pocket until you reach catastrophic coverage. In 2024, the gap begins after combined spending of $5,850 and ends at $7,050 in out-of-pocket costs. These numbers change each year.

If your income is low or modest, you may be may be able to access for Extra Help (also called the Low-Income Subsidy program). This federal program pays some or all of your Part D costs — premiums, deductibles, and copays. You can check whether you may have access to by going to Medicare.gov or calling 1-800-MEDICARE. The income limits vary by state and household size, but many people earning under $20,000 a year (or couples earning under $27,000) may have access to.

If you get Extra Help, you still choose a Part D plan, but your costs are much lower. Some plans are designated as "Extra Help may be able to access," meaning they work smoothly with the subsidy program. When you enroll, tell Medicare if you receive Extra Help so your plan is set up correctly from the start.

What happens after you enroll

Once you enroll in a Part D plan, your coverage begins on the first day of the following month (or January 1 if you enroll in November or December). You will receive a member ID card in the mail, usually within two weeks. Use this card at the pharmacy when you fill prescriptions.

Your plan will send you a document called the Summary of Benefits and Coverage, which lists exactly which drugs are covered, at what cost, and any restrictions (such as prior authorization or quantity limits). Read this carefully when it arrives, because it may differ from what you saw during comparison. If a drug you take is not covered or has a high copay, you can ask your doctor to request an exception, or you can switch to a different plan during the next open enrollment period.

Keep your member ID card with you and update your address with your plan if you move. If your medications change or your financial situation changes, you may be able to switch plans outside of open enrollment — ask your plan or call Medicare to find out.

Signing up if you already have Medicare

If you already have Medicare Part A and Part B but do not have Part D coverage, you can enroll during the annual open enrollment period (October 15 to December 7) or if you have a may have access to life event. A may have access to event includes losing employer or union drug coverage, moving to a new state, or becoming may be able to access for Extra Help.

You do not need to contact Medicare to report a may have access to event; instead, contact the Part D plan you want to join directly, or call 1-800-MEDICARE and tell them what happened. They will verify your event and let you know whether you can enroll outside the normal window. If you do not have a may have access to event and you miss open enrollment, you will have to wait until the next October to sign up, and you will owe the late penalty.

Getting help choosing a plan

If comparing plans feels overwhelming, free counseling is available in your area. State Health Insurance information Programs (SHIP) offer one-on-one help at no cost. A counselor will review your medications, your budget, and your pharmacy, then recommend specific plans. To find your local SHIP, go to Medicare.gov or call 1-800-MEDICARE.

You can also speak with a licensed insurance broker or agent who specializes in Medicare. Many do not charge you directly — they are paid by the insurance companies — but always ask upfront whether there is a fee. Some community health centers and senior centers also host Medicare enrollment events where you can get help in person.

If you speak a language other than English, Medicare.gov has materials in many languages, and interpreters are available by phone when you call 1-800-MEDICARE.

What to do if you miss the enrollment important date

If you miss the important date to sign up when you first turn 65 or during open enrollment, you can still enroll, but you will owe a late penalty. The penalty is 1% of the national average Part D premium for each month you did not have coverage. In 2024, the national average premium is around $34, so the penalty is roughly 34 cents per month for each month you were uninsured — but this amount changes yearly and compounds over time.

You can enroll outside the normal window only if you have a may have access to life event. If you do not, you will have to wait until the next open enrollment period in October. In the meantime, if you need prescriptions, talk to your doctor about lower-cost options, ask your pharmacy about discount programs, or look into community health center programs that may offer reduced-cost medications.

Frequently Asked Questions

Do I have to sign up for Part D when I turn 65?

No, but if you do not have other drug coverage and you do not sign up, you will owe a late penalty when you eventually do. If you have drug coverage through an employer or union, you can delay signing up without penalty as long as that coverage continues. When it ends, you have 63 days to sign up for Part D.

Can I change my Part D plan if I do not like it?

Yes, during the annual open enrollment period (October 15 to December 7) you can switch to a different plan. Your new coverage will start January 1. If you have a may have access to life event, such as losing coverage or moving, you may be able to switch outside this window.

What if my Part D plan stops covering one of my medications?

Contact your plan and ask whether the drug is still covered or whether there are restrictions. If it is no longer covered, ask your doctor whether a similar drug on the plan's formulary would work for you. You can also request an exception from the plan. If you cannot get the coverage you need, you can switch to a different plan during open enrollment.

Will Part D cover all of my prescriptions?

No. Each plan has a formulary — a list of covered drugs — and it varies by plan. Some drugs may require prior authorization from your doctor, or they may have quantity limits. Use the Plan Finder tool to check whether your specific medications are covered before you enroll.

What if I cannot afford my Part D premiums?

If your income is low, you may be may be able to access for Extra Help, which pays some or all of your Part D costs. You can check your may be able to access at Medicare.gov or by calling 1-800-MEDICARE. You can also ask your plan about payment plans or hardship programs if you fall behind on payments.