When You Can Sign Up for Medicare Part D Coverage

Medicare Part D enrollment windows and important date

You can sign up for Medicare Part D during three main periods each year, and the timing depends on whether you are new to Medicare or already enrolled. Missing these windows usually means waiting until the next one opens, unless you have a may have access to life event like losing employer coverage.

The Initial Enrollment Period is a seven-month window that starts three months before the month you turn 65 and ends three months after. If you are already on Medicare Part A or Part B when you turn 65, your Part D enrollment period runs on the same schedule. You can sign up anytime during these seven months, and coverage can start as early as the first day of the month you turn 65.

The Annual Enrollment Period runs from October 15 through December 7 each year. This is when anyone already on Medicare can switch plans, drop coverage, or sign up for the first time if they missed their Initial Enrollment Period. Coverage from plans you choose during this window starts January 1 of the following year.

If you did not sign up during your Initial Enrollment Period and you do not have other drug coverage, you will pay a late enrollment penalty for as long as you have Part D. The penalty is calculated based on how many months you went without coverage, and it gets added to your monthly premium. The exact amount varies by year, but waiting even a few months can add up to a permanent increase in what you pay.

Key Takeaways

Your Initial Enrollment Period is seven months long, starting three months before you turn 65 and ending three months after, and you can start coverage as early as the month you turn 65.
The Annual Enrollment Period from October 15 through December 7 is when you can change plans or sign up if you missed your initial window.
If you go without Part D coverage when you are first may be able to access and do not have other drug coverage, you will owe a late enrollment penalty on top of your regular premium for as long as you have Part D.
Certain life events like losing employer coverage or moving to a new state can open a Special Enrollment Period outside the regular windows.
You sign up through Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.

What counts as other drug coverage

If you have prescription drug coverage through a current or former employer, a union, TRICARE, the Veterans Administration, or a state Medicaid program, you may not owe a late enrollment penalty even if you do not sign up for Part D right away. The key is that your coverage must be creditable — meaning it covers at least as much as Part D does on average.

When you leave that coverage, you have 63 days to sign up for Part D without a penalty. If you wait longer than 63 days, the penalty applies. Your employer or plan administrator should send you a notice saying whether your coverage is creditable; keep this document because you may need to show it later.

If you are unsure whether your current coverage counts, call the plan directly and ask if it is creditable for Medicare purposes. You can also call 1-800-MEDICARE and ask them to check your specific situation.

Special Enrollment Periods for life changes

If you experience certain life events, you can sign up for Part D outside the regular enrollment windows. These Special Enrollment Periods usually last 60 days from the date of the event, though the exact timing depends on what happened.

Common may have access to events include losing employer or union drug coverage, moving to a different state, having a change in your Medicaid status, or being released from prison. If you are turning 65 while still working and covered by your employer's plan, you can delay Part D without penalty as long as you sign up within 63 days of losing that coverage.

To report a life event and open a Special Enrollment Period, contact Medicare at 1-800-MEDICARE or go to Medicare.gov and log into your account. You will need to describe what happened and provide a date. Medicare will tell you whether the event qualifies and when your enrollment window closes.

How to sign up during your enrollment window

You have three ways to enroll in a Part D plan: online at Medicare.gov, by phone, or in person. The online method is fastest — you can compare plans, see what your costs will be for the drugs you take, and complete enrollment in one session.

To use Medicare.gov, go to the Plan Finder tool and enter your zip code, the drugs you take (including the dose and how often), and your pharmacy. The tool will show you plans ranked by cost, and you can see your estimated out-of-pocket expenses for the year. Once you choose a plan, you can enroll right there. You will need your Medicare number, which is on your Medicare card.

If you prefer to enroll by phone, call 1-800-MEDICARE (1-800-633-4227). Representatives are available seven days a week, and they can walk you through the plan options and answer questions about costs. If you need help in a language other than English, Medicare has interpreters available.

You can also visit your local Social Security office in person to enroll, though this is slower than the other two methods. Bring your Medicare card and a list of your current medications.

What happens after you enroll

Once you enroll in a Part D plan, you should receive a confirmation letter within two weeks. This letter will have your plan name, member ID number, and the date your coverage starts. Keep this letter and your new insurance card when it arrives.

Your coverage starts on the first day of the month after you enroll, unless you enroll during your Initial Enrollment Period before you turn 65 — then it can start the month you turn 65. If you enroll during the Annual Enrollment Period in October or November, coverage starts January 1.

Before your coverage starts, review your plan's formulary, which is the list of drugs it covers. You can find this on the plan's website or call the plan's customer service number. If one of your regular medications is not on the formulary, contact the plan to ask about coverage options or request an exception.

When you can change or drop your plan

Once you are enrolled in a Part D plan, you can only change plans during the Annual Enrollment Period in October and November, or if you have a may have access to life event. You cannot switch plans in the middle of the year just because you want to, even if you find a cheaper option.

If you want to drop Part D coverage entirely, you can do so during the Annual Enrollment Period. However, if you drop coverage and do not have other creditable drug coverage, you will owe a late enrollment penalty if you sign up again later. The only exception is if you are dropping Part D because you are enrolling in a Medicare Advantage plan that includes drug coverage.

If your plan changes its formulary or raises its costs significantly, you may be able to request a Special Enrollment Period to switch plans outside the regular window. Call your plan or Medicare to ask whether your situation qualifies.

Frequently Asked Questions

What if I turn 65 while still working and have employer drug coverage?

You can delay signing up for Part D without penalty as long as your employer coverage is creditable. When you leave that job or lose the coverage, you have 63 days to enroll in Part D. If you wait longer, you will owe a late enrollment penalty. Ask your employer for a creditable coverage notice to keep as proof.

Can I sign up for Part D after the Annual Enrollment Period ends?

No, unless you have a may have access to life event like losing other drug coverage, moving states, or a change in Medicaid status. If you miss both your Initial Enrollment Period and the Annual Enrollment Period, you will have to wait until the next October to sign up, and you will owe a late enrollment penalty.

How much is the late enrollment penalty?

The penalty amount changes each year and is based on how many months you went without Part D coverage when you were first may be able to access. It is calculated as a percentage of the national average Part D premium and gets added to your monthly premium permanently. The exact dollar amount depends on the year and your plan.

Do I have to use the Plan Finder tool to enroll?

No. You can enroll by calling 1-800-MEDICARE or visiting a Social Security office in person. However, the Plan Finder tool on Medicare.gov lets you see your estimated costs for specific drugs at specific pharmacies, which helps you pick the cheapest plan for your situation.

What if my plan stops offering Part D coverage?

If your plan discontinues drug coverage, Medicare will send you a notice at least 30 days in advance. You can then enroll in a different Part D plan outside the regular enrollment window without owing a late enrollment penalty. Contact Medicare or your current plan for details on when you need to switch.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.