When to Sign Up for Medicare: Enrollment Periods Explained

Timing matters with Medicare. Signing up during the right window helps you avoid gaps in coverage and penalties that can add to your premiums for years. Here is an overview of the main enrollment periods. Rules can be detailed, so confirm your situation with Medicare, Social Security or your State Health Insurance Assistance Program.

Automatic vs. manual enrollment

If you are already receiving Social Security or Railroad Retirement Board benefits when you turn 65, you will generally be enrolled in Parts A and B automatically and receive your Medicare card in the mail before your birthday month.

If you are not yet receiving those benefits, you usually need to sign up yourself, which you can do online through Social Security, by phone or at a local office.

Initial Enrollment Period (IEP)

Your Initial Enrollment Period is a seven-month window that:

• Begins three months before the month you turn 65
• Includes the month you turn 65
• Ends three months after the month you turn 65

Signing up during the three months before your birthday month means coverage generally starts the first day of your birthday month. If you sign up during your birthday month or the three months after, coverage generally starts the first day of the month after you sign up.

Special Enrollment Period (SEP) for job-based coverage

If you or your spouse are still working and you have health coverage through that current employment, you may be able to delay Part B without a penalty. You can then sign up during a Special Enrollment Period:

• Any time you are still covered by the group health plan based on current employment, or
• During the eight months after the employment or the coverage ends, whichever happens first.

Important details:

• COBRA and retiree health coverage do not count as coverage based on current employment for this purpose.
• Rules can differ based on employer size. Ask your employer's benefits office how its plan works with Medicare.
• Keep documentation of your employer coverage, since you may need to show it when you sign up.

General Enrollment Period (GEP)

If you missed your Initial Enrollment Period and do not qualify for a Special Enrollment Period, you can sign up for Part A and/or Part B during the General Enrollment Period, January 1 through March 31 each year. Coverage starts the month after you sign up. You may have to pay a late enrollment penalty.

Late enrollment penalties

Part B: Your monthly premium may go up 10 percent for each full 12-month period you could have had Part B but did not sign up. In most cases, you pay this penalty for as long as you have Part B.

Part D: If you go 63 days or more in a row without Part D or other creditable drug coverage after your Initial Enrollment Period ends, you may owe a late enrollment penalty added to your premium, generally for as long as you have Part D coverage.

Part A: Most people get premium-free Part A. If you must buy Part A and sign up late, your premium may go up for a period of time.

Annual enrollment periods after you have Medicare

• Medicare Open Enrollment (October 15 to December 7): change Medicare Advantage or Part D plans, or switch between Original Medicare and Medicare Advantage. Changes take effect January 1.
• Medicare Advantage Open Enrollment (January 1 to March 31): if you are in a Medicare Advantage plan, you can switch to another Medicare Advantage plan or go back to Original Medicare once during this period.

A simple checklist as you approach 65

1. Mark your Initial Enrollment Period on your calendar.
2. Decide whether you need to sign up or will be enrolled automatically.
3. If you are working, ask your employer how its coverage works with Medicare.
4. Review whether you will choose Original Medicare or Medicare Advantage.
5. Plan for drug coverage to avoid a Part D penalty.
6. Contact your SHIP for free counseling if you have questions.

Terrameritavi is an independent publication and is not affiliated with Medicare or any government agency. Always confirm your enrollment options with official sources.