Understanding Medicare 

Part C & Part D Enrollment Periods

Revised October 2018

Enrollment in Medicare is limited to certain times. This publication 

has information about enrolling in Medicare Advantage Plans 

(Part C) and Medicare Prescription Drug Plans (Part D), including 

who can sign up, when to sign up, and how the timing, including 

signing up late, can affect your costs. 

Note: For information about signing up for Medicare Part A 

(Hospital Insurance) and Medicare Part B (Medical Insurance), 

visit Medicare.gov/publications to view the booklet “Enrolling in 

Medicare Part A & Part B.” 
2

When can I sign up? 

There are specific times when you can sign up for a Medicare Advantage Plan 

(like an HMO or PPO) or Medicare prescription drug coverage, or make changes 

to coverage you already have: 

■ During your Initial Enrollment Period when you first become eligible for 

Medicare or when you turn 65. See page 3. 

■ During certain enrollment periods that happen each year. See page 5.

■ Under certain circumstances that qualify you for a Special Enrollment Period 

(SEP), like: 

■ You move.

■ You’re eligible for Medicaid. 

■ You qualify for Extra Help with Medicare prescription drug costs. 

■ You’re getting care in an institution, like a skilled nursing facility or 

long‐term care hospital. 

■ You want to switch to a plan with a 5-star overall quality rating. Quality 

ratings are available on Medicare.gov. 

See the charts beginning on page 7 for a list of different SEPs, including rules 

about how to qualify. 

Note about joining a Medicare Advantage Plan 

You must have Medicare Part A and Part B to join a Medicare Advantage Plan. 

In most cases, if you have End-Stage Renal Disease (ESRD), you can’t join a 

Medicare Advantage Plan. 
3

Initial Enrollment Periods 

If this describes you... You can... At this time... 

You’re newly eligible for 

Medicare because you turn 65. 

Sign up for a Medicare 

Advantage Plan (with or 

without prescription drug 

coverage) or a Medicare 

Prescription Drug Plan. 

During the 7-month period 

that starts 3 months before 

the month you turn 65, 

includes the month you turn 

65, and ends 3 months after 

the month you turn 65. 

If you sign up for a Medicare 

Advantage Plan during this 

time, you can drop that plan 

at any time during the next 

12 months and go back to 

Original Medicare. 

You’re newly eligible for 

Medicare because you have a 

disability and you’re under 65. 

Sign up for a Medicare 

Advantage Plan (with or 

without prescription drug 

coverage) or a Medicare 

Prescription Drug Plan. 

Starting 21 months after 

you get Social Security or 

Railroad Retirement Board 

(RRB) disability benefits. 

Your Medicare coverage 

begins 24 months after you 

get Social Security or RRB 

benefits. Your chance to sign 

up lasts through the 28th 

month after you get Social 

Security or RRB benefits. 

You’re already eligible 

for Medicare because of a 

disability, and you turn 65. 

■ Sign up for a Medicare 

Advantage Plan (with or 

without prescription drug 

coverage) or a Medicare 

Prescription Drug Plan. 

■ Switch from your current 

Medicare Advantage or 

Medicare Prescription 

Drug Plan to another plan. 

■ Drop a Medicare 

Advantage or Medicare 

Prescription Drug Plan 

completely. 

During the 7-month period 

that starts 3 months before 

the month you turn 65, 

includes the month you turn 

65, and ends 3 months after 

the month you turn 65. 

You have Medicare Part A 

coverage, and you get Part B 

for the first time by enrolling 

during the Part B General 

Enrollment Period 

(January 1–March 31). 

Sign up for a Medicare 

Advantage Plan (with or 

without prescription drug 

coverage). 

Between April 1–June 30. 
4

Part D late enrollment penalty 

The late enrollment penalty is an amount that’s added to your Part D premium. 

You may owe a late enrollment penalty if at any time after your Initial Enrollment 

Period is over, there’s a period of 63 or more days in a row when you don’t have 

Part D or other creditable prescription drug coverage. Creditable prescription drug 

coverage is coverage (for example, from an employer or union) that’s expected to 

pay, on average, at least as much as Medicare’s standard prescription drug coverage. 

If you have a penalty, you may have to pay it each month for as long as you have 

Medicare drug coverage. For more information about the late enrollment penalty, 

visit Medicare.gov, or call 1-800-MEDICARE (1-800-633-4227). TTY users can call 

1-877-486-2048. 
5

Enrollment periods that happen each year 

Each year, you can make changes to your Medicare Advantage or Medicare prescription 

drug coverage for the following year. There are 2 separate enrollment periods each year. 

See the chart below for specific dates. 

During this enrollment 

period... You can...

October 15–December 7 

(Changes will take effect on 

January 1.)

■ Change from Original Medicare to a Medicare Advantage 

Plan. 

■ Change from a Medicare Advantage Plan back to Original 

Medicare. 

■ Switch from one Medicare Advantage Plan to another 

Medicare Advantage Plan. 

■ Switch from a Medicare Advantage Plan that doesn’t offer 

drug coverage to a Medicare Advantage Plan that offers drug 

coverage. 

■ Switch from a Medicare Advantage Plan that offers drug 

coverage to a Medicare Advantage Plan that doesn’t offer drug 

coverage. 

■ Join a Medicare Prescription Drug Plan. 

■ Switch from one Medicare Prescription Drug Plan to another 

Medicare Prescription Drug Plan. 

■ Drop your Medicare prescription drug coverage completely. 

January 1–March 31

Medicare Advantage Open 

Enrollment Period

(You can only make one 

change during this period. 

Changes will take effect the 

first of the month after the 

plan gets your request.)

■ If you’re in a Medicare Advantage Plan (with or without drug 

coverage), switch to another Medicare Advantage Plan (with 

or without drug coverage).

■ Disenroll from your Medicare Advantage Plan and return to 

Original Medicare. If you choose to do so, you’ll be able to 

join a Medicare Prescription Drug Plan.

■ If you enrolled in a Medicare Advantage Plan during your 

Initial Enrollment Period, change to another Medicare 

Advantage Plan (with or without drug coverage) or go back to 

Original Medicare (with or without drug coverage) within the 

first 3 months you have Medicare. 

You can’t... 

■ Switch from Original Medicare to a Medicare Advantage Plan.

■ Join a Medicare Prescription Drug Plan if you’re in Original 

Medicare.

■ Switch from one Medicare Prescription Drug Plan to another 

if you’re in Original Medicare.
6

Special Enrollment Periods 

You can make changes to your Medicare health and Medicare prescription 

drug coverage when certain events happen in your life, like if you move 

or you lose other insurance coverage. These chances to make changes are 

called Special Enrollment Periods (SEPs) and are in addition to the regular 

enrollment periods that happen each year. Rules about when you can make 

changes and the type of changes you can make are different for each SEP. 

The SEPs listed on the next pages are examples. This list doesn’t include 

every situation. For more information about SEPs, call 1-800-MEDICARE 

(1-800-633-4227). TTY users can call 1-877-486-2048. 
7

Changes in where you live 

If this describes you... You can... At this time... 

You move to a new address 

that isn’t in your plan’s 

service area.* 

Switch to a new Medicare 

Advantage or Medicare 

Prescription Drug Plan. 

* Note: If you’re in a Medicare 

Advantage Plan and you 

move outside your plan’s 

service area, you can also 

choose to return to Original 

Medicare. If you don’t enroll 

in a new Medicare Advantage 

Plan during this SEP, you’ll be 

enrolled in Original Medicare 

when you’re disenrolled from 

your old Medicare Advantage 

Plan. 

If you tell your plan 

before you move, your 

chance to switch plans 

begins the month before 

the month you move 

and continues for 2 full 

months after you move. 

If you tell your plan 

after you move, your 

chance to switch plans 

begins the month you 

tell your plan, plus 2 

more full months.

You move to a new address 

that’s still in your plan’s 

service area, but you have 

new plan options in your new 

location. 

You move back to the U.S. 

after living outside the 

country. 

Join a Medicare Advantage or 

Medicare Prescription Drug 

Plan. 

Your chance to join lasts 

for 2 full months after 

the month you move 

back to the U.S. 

You just moved into, 

currently live in, or just 

moved out of an institution 

(like a skilled nursing facility 

or long-term care hospital). 

■ Join a Medicare Advantage 

or Medicare Prescription 

Drug Plan. 

■ Switch from your current 

plan to another Medicare 

Advantage or Medicare 

Prescription Drug Plan. 

■ Drop your Medicare 

Advantage Plan and return 

to Original Medicare. 

■ Drop your Medicare 

prescription drug coverage. 

Your chance to join, 

switch, or drop coverage 

lasts as long as you live 

in the institution and for 

2 full months after the 

month you move out of 

the institution. 

You’re released from jail. Join a Medicare Advantage or 

Medicare Prescription Drug 

Plan. 

Your chance to join 

lasts for 2 full months 

after the month you’re 

released from jail. 
8

Changes that cause you to lose your current coverage 

If this describes you... You can... At this time... 

You’re no longer eligible for 

Medicaid. 

■ Join a Medicare Advantage 

or Medicare Prescription 

Drug Plan. 

■ Switch from your current 

plan to another Medicare 

Advantage or Medicare 

Prescription Drug Plan. 

■ Drop your Medicare 

Advantage Plan and return 

to Original Medicare. 

■ Drop your Medicare 

prescription drug coverage. 

(New for 2019) Your chance to 

change lasts for 3 full months 

from either the date you’re 

no longer eligible or notified, 

whichever is later. 

You find out that you won’t be 

eligible for Extra Help for the 

following year. 

■ Join a Medicare Advantage 

or Medicare Prescription 

Drug Plan. 

■ Switch from your current 

plan to another Medicare 

Advantage or Medicare 

Prescription Drug Plan. 

■ Drop your Medicare 

Advantage Plan and return 

to Original Medicare. 

■ Drop your Medicare 

prescription drug coverage. 

(New for 2019) Your chance to 

change lasts for 3 full months 

from either the date you’re 

no longer eligible or notified, 

whichever is later. 

You leave coverage from your 

employer or union. 

Join a Medicare Advantage or 

Medicare Prescription Drug 

Plan. 

Your chance to join lasts for 2 

full months after the month 

your coverage ends. 

You involuntarily lose other 

drug coverage that’s as good 

as Medicare drug coverage 

(creditable coverage), or your 

other coverage changes and is 

no longer creditable. 

Join a Medicare Advantage 

Plan with drug coverage or a 

Medicare Prescription Drug 

Plan. 

Your chance to join lasts for 2 

full months after the month 

you lose your creditable 

coverage or are notified of the 

loss of creditable coverage, 

whichever is later. 

You have drug coverage 

through a Medicare Cost Plan 

and you leave the plan. 

Join a Medicare Prescription 

Drug Plan. 

Your chance to join lasts for 2 

full months after the month 

you drop your Medicare Cost 

Plan. 

You drop your coverage in a 

Program of All-inclusive Care 

for the Elderly (PACE) Plan. 

Join a Medicare Advantage or 

Medicare Prescription Drug 

Plan. 

Your chance to join lasts for 2 

full months after the month 

you drop your PACE plan. 
9

You have a chance to get other coverage 

If this describes you... You can... At this time... 

You have a chance to enroll in 

other coverage offered by your 

employer or union. 

Drop your current Medicare 

Advantage or Medicare 

Prescription Drug Plan to 

enroll in the private plan 

offered by your employer or 

union. 

Whenever your employer or 

union allows you to make 

changes in your plan. 

You have or are enrolling in 

other drug coverage as good 

as Medicare prescription drug 

coverage (like TRICARE or VA 

coverage). 

Drop your current Medicare 

Advantage Plan with drug 

coverage or your Medicare 

Prescription Drug Plan. 

Anytime. 

You enroll in a Program of 

All-inclusive Care for the 

Elderly (PACE) Plan. 

Drop your current Medicare 

Advantage or Medicare 

Prescription Drug Plan. 

Anytime. 

You live in the service area 

of one or more Medicare 

Advantage or Medicare 

Prescription Drug Plans with 

an overall quality rating of 5 

stars. 

Join a Medicare Advantage, 

Medicare Cost, or Medicare 

Prescription Drug Plan with an 

overall quality rating of 5 stars. 

One time between 

December 8–November 30. 

Changes in your plan’s contract with Medicare 

If this describes you... You can... At this time... 

Medicare takes an official 

action (called a “sanction”) 

because of a problem with the 

plan that affects you. 

Switch from your Medicare 

Advantage or Medicare 

Prescription Drug Plan to 

another plan. 

Your chance to switch is 

determined by Medicare on 

a case-by-case basis. 

Your plan’s contract ends 

(terminates) during the 

contract year. 

Switch from your Medicare 

Advantage or Medicare 

Prescription Drug Plan to 

another plan. 

Your chance to switch starts 

2 months before and ends 1 

full month after the contract 

ends. 

Your Medicare Advantage Plan, 

Medicare Prescription Drug 

Plan, or Medicare Cost Plan’s 

contract with Medicare isn’t 

renewed for the next contract 

year.

Switch from your Medicare 

Advantage or Medicare 

Prescription Drug Plan to 

another plan. 

Between October 15 and the 

last day in February. 
10

Changes due to other special situations

If this describes you... You can... At this time... 

You’re eligible for both 

Medicare and Medicaid. 

Join, switch, or drop a 

Medicare Advantage Plan or 

Medicare prescription drug 

coverage. 

(New for 2019) Once during each 

of these periods:

■ January–March

■ April–June

■ July–September

(You can also make a change 

from October 15–December 7, 

and the change will take effect on 

January 1.) 

You get Extra Help paying for 

Medicare prescription drug 

coverage. 

Join, switch, or drop 

Medicare prescription drug 

coverage. 

(New for 2019) Once during each 

of these periods:

■ January–March

■ April–June

■ July–September

(You can also make a change 

from October 15–December 7, 

and the change will take effect on 

January 1.) 

You’re enrolled in a State 

Pharmaceutical Assistance 

Program (SPAP). 

Join either a Medicare 

Prescription Drug Plan 

or a Medicare Advantage 

Plan with prescription drug 

coverage. 

Once during the calendar year. 

You’re enrolled in a State 

Pharmaceutical Assistance 

Program (SPAP) and you lose 

SPAP eligibility. 

Join either a Medicare 

Prescription Drug Plan 

or a Medicare Advantage 

Plan with prescription drug 

coverage. 

Your chance to switch starts either 

the month you lose eligibility or 

are notified of the loss, whichever 

is earlier. It ends 2 months after 

either the month of the loss of 

eligibility or notification of the 

loss, whichever is later. 

You dropped a Medicare 

Supplemental Insurance 

(Medigap) policy the first 

time you joined a Medicare 

Advantage Plan. 

Drop your Medicare 

Advantage Plan and enroll 

in Original Medicare. You’ll 

have special rights to buy a 

Medigap policy. 

Your chance to drop your 

Medicare Advantage Plan lasts 

for 12 months after you join the 

Medicare Advantage Plan for the 

first time. 

You have a severe or disabling 

condition, and there’s a 

Medicare Chronic Care 

Special Needs Plan (SNP) 

available that serves people 

with your condition. 

Join a Medicare Chronic 

Care SNP that serves people 

with your condition. 

You can join anytime, but once 

you join, your chance to make 

changes using this SEP ends. 
11

If this describes you... You can... At this time...

You joined a plan, or chose not 

to join a plan, due to an error 

by a federal employee. 

■ Join a Medicare Advantage 

Plan with drug coverage or a 

Medicare Prescription Drug 

Plan. 

■ Switch from your current 

plan to another Medicare 

Advantage Plan with drug 

coverage or a Medicare 

Prescription Drug Plan. 

■ Drop your Medicare 

Advantage Plan with drug 

coverage and return to 

Original Medicare. 

■ Drop your Medicare 

prescription drug coverage. 

Your chance to change 

coverage lasts for 2 full 

months after the month 

you get a notice of the 

error from Medicare. 

You weren’t properly told 

that your other private drug 

coverage wasn’t as good as 

Medicare drug coverage 

(creditable coverage). 

Join a Medicare Advantage 

Plan with drug coverage or a 

Medicare Prescription Drug 

Plan. 

Your chance to join lasts 

for 2 full months after the 

month you get a notice of 

the error from Medicare. 

You weren’t properly told that 

you were losing private drug 

coverage that was as good 

as Medicare drug coverage 

(creditable coverage). 

Join a Medicare Advantage 

Plan with drug coverage or a 

Medicare Prescription Drug 

Plan. 

Your chance to join lasts 

for 2 full months after the 

month you get a notice of 

the error from Medicare. 

You don’t have Part A coverage, 

and you enroll in Medicare Part 

B during the Part B General 

Enrollment Period 

(January 1–March 31). 

Join a Medicare Prescription 

Drug Plan. 

Between April 1–June 30. 
CMS Product No. 11219

You have the right to get Medicare information in an accessible format, like large 

print, Braille, or audio. You also have the right to file a complaint if you feel you’ve 

been discriminated against. Visit Medicare.gov/about-us/nondiscrimination/

accessibility-nondiscrimination.html, or call 1-800-MEDICARE (1-800-633-4227) 

for more information. TTY users can call 1-877-486-2048.

Paid for by the Department of Health & Human Services.

Get more information 

For more detailed information about signing up, including instructions 

on how to join, visit Medicare.gov. You can also call 1-800-MEDICARE 

(1-800-633-4227). TTY users can call 1-877-486-2048. 

Extra Help is available! 

If you have limited income and resources, you may be able to get Extra 

Help paying your prescription drug coverage costs. People who qualify 

may be able to get their prescriptions filled and pay little or nothing out of 

pocket. You can apply for Extra Help at any time. There’s no cost to apply 

for Extra Help, so you should apply even if you’re not sure if you qualify. 

To apply online, visit socialsecurity.gov/i1020. Or, call Social Security at 

1‐800‐772‐1213 to apply by phone or get a paper application. TTY users 

can call 1‐800‐325‐0778.