What Part D Is and When You Can Sign Up

Part D is Medicare's prescription drug coverage. It pays toward the cost of medications your doctor prescribes. You do not have to take it, but if you go without coverage for a long time and then join later, you will usually pay a higher monthly premium for the rest of your life.

You can sign up during your Initial Enrollment Period, which is the seven-month window that starts three months before the month you turn 65 and ends three months after. If you miss this window, you can still join during the Annual Enrollment Period from October 15 to December 7 each year, with coverage starting January 1.

If you already have health coverage through an employer or union, you may not need Part D right away. But if that coverage ends, you have 63 days to sign up for Part D without paying the late penalty.

Key Takeaways

  • You can sign up for Part D online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
  • Your Initial Enrollment Period is seven months long, starting three months before you turn 65, and missing it usually means paying a higher premium permanently.
  • Part D plans vary widely in cost and which drugs they cover, so comparing plans before you choose is important even if you have used the same pharmacy for years.
  • You will need your Medicare card or Social Security number to sign up, and you should know which medications you take before you start.
  • If you have low income, you may pay little or nothing for Part D through the Low-Income Subsidy program, which you can ask about during sign-up.

How to Sign Up Online at Medicare.gov

The fastest way to sign up is through Medicare.gov. Go to the homepage and look for the link that says "Sign up for Part D." You will need your Medicare number (on your red, white, and blue Medicare card) or your Social Security number.

The site will ask you to enter your zip code and show you all Part D plans available in your area. Each plan shows the monthly premium, the drugs it covers, and which pharmacies you can use. You can compare up to three plans side by side. Once you choose, you complete the sign-up right there and receive a confirmation number.

Coverage usually starts on the first day of the following month if you sign up before the 15th. If you sign up after the 15th, coverage starts two months later.

Signing Up by Phone or In Person

If you prefer to talk to someone, call 1-800-MEDICARE (1-800-633-4227). Representatives are available seven days a week, from 8 a.m. to 8 p.m. your local time. Have your Medicare card or Social Security number ready, and know which medications you take and which pharmacy you use.

You can also visit your local Social Security office to sign up in person. Find the nearest office at ssa.gov or call 1-800-772-1213. Bring your Medicare card and a list of your current medications.

Choosing a Plan That Covers Your Medications

Part D plans do not all cover the same drugs. Before you sign up, make a list of every medication you take, including the dose and how often you take it. Then use the "Find Care Providers and Suppliers" tool on Medicare.gov to check which plans cover each one.

Plans are organized into tiers — usually four or five levels. Drugs on lower tiers cost you less out of pocket. A medication on Tier 1 might cost $5 a month, while the same drug on Tier 3 could cost $50. If your doctor prescribes a brand-name drug but a generic version exists on a lower tier, ask your doctor whether the generic would work for you.

Also check which pharmacies each plan uses. Some plans work with most pharmacies in your area; others have a smaller network. If you have a pharmacy you trust, make sure it is in the plan's network before you sign up.

Understanding the Costs You Will Pay

Part D has four cost stages each year. First, you pay a monthly premium — the amount varies by plan and ranges widely. Second, you pay a deductible (usually $505 to $550, though this amount changes each year) before the plan starts paying. Third, you pay copayments or coinsurance — your share of the drug cost — until you and the plan together have spent $5,735 out of pocket. Fourth, you enter the coverage gap, where you pay a higher percentage of drug costs until your total spending reaches $8,550, at which point catastrophic coverage begins and you pay only a small copay.

These amounts change every January. You can see the current year's amounts on Medicare.gov before you choose a plan.

What to Do If You Have Low Income

If your income is below a certain level (which varies by state but is roughly 150% to 200% of the federal poverty line), you may pay little or nothing for Part D through the Low-Income Subsidy program, also called "Extra Help." This program covers your premium, deductible, and copayments.

You can ask about the Low-Income Subsidy when you sign up for Part D, or you can explore separately through Social Security. Call 1-800-772-1213 or visit your local Social Security office. You will need to show proof of income, such as recent tax returns or pay stubs.

After You Sign Up

Once you are enrolled, you will receive a Part D plan card in the mail before your coverage starts. Show this card at the pharmacy when you pick up prescriptions. Keep it with you at all times.

Your coverage runs from January 1 to December 31 each year. If you want to change plans, you can do so during the Annual Enrollment Period from October 15 to December 7. Changes take effect January 1. You cannot change plans outside this window unless you have a may have access to life event, such as moving to a new state or losing other health coverage.

If your medications or health needs change during the year, contact your plan to ask whether a different plan might save you money. Some plans allow you to switch mid-year if your circumstances change.

Frequently Asked Questions

What happens if I miss my Initial Enrollment Period?

You can still sign up during the Annual Enrollment Period each October 15 to December 7, with coverage starting January 1. However, you will pay a late enrollment penalty — usually 1% of the national average Part D premium for each month you went without coverage. This penalty is added to your monthly premium permanently, even if you switch plans later.

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

Yes, but only during the Annual Enrollment Period from October 15 to December 7. You can switch to any other plan available in your area, and the change takes effect January 1. If you have a may have access to life event — such as moving, losing other coverage, or a major change in your health — you may be able to switch outside this window.

Do I have to use the pharmacy listed in my plan?

Most Part D plans have a network of pharmacies where you pay the lower copay. If you use an out-of-network pharmacy, you will pay more. However, plans usually allow you to use any pharmacy for emergency medications. Check your plan's pharmacy list before you sign up if you have a pharmacy you prefer.

What if my doctor prescribes a drug that my Part D plan does not cover?

You can ask your doctor to prescribe a different drug that the plan does cover, or you can ask the plan for an exception. Some plans will cover a non-formulary drug if your doctor explains why you need it. This process is called a "formulary exception" and usually takes a few days.

Do I need Part D if I take very few medications?

That depends on your situation. If you think you might need prescriptions in the future, signing up during your Initial Enrollment Period protects you from the late penalty. Even a low-cost plan with a high deductible is better than no coverage if you have an unexpected health event. If you are certain you will never need prescriptions, you can decline Part D, but you cannot change your mind without paying the penalty.