The Medicare Enrollment Timeline

The periods for enrolling in the various Medicare parts are very specific and rigid. Right around your 65th birthday is when you need to have all your choices made, so it’s best to plan well ahead of time. If you miss these windows, you may have to pay more and have fewer choices.

Here are the details:

  1. Part A – Seven-month period    

    • You can enroll three months before your 65th birthday, your birthday month and three months after.
    • If you have a qualifying disability, you can join during the three months before to the three months after your 25th month of disability.
    • Part A is premium free if you or your spouse worked the required 10 years to be eligible.
    • If you are not eligible for premium-free Part A, late penalties may apply.
  2. Part B – Seven-month period

    • You can enroll three months before your 65th birthday, your birthday month and three months after.
    • If you have a qualifying disability, you can join during the three months before to the three months after your 25th month of disability.
    • If you enroll later, your premiums could be higher. 
    • There is a special enrollment period for working individuals.
  3. Part C (Medicare Advantage) – Seven-month period

    • You can enroll three months before your 65th birthday, your birthday month and three months after.
    • If you have a qualifying disability, you can join during the three months before to the three months after your 25th month of disability.
    • If you miss your initial enrollment period, you must wait until the next annual enrollment period, which usually takes place in the fall. 
    • Your plan can never be effective prior to the date that you are eligible for Parts A and B.
    • Enrollment is never retrospective.
  4. Part D (and Stand-Alone PDP) – Seven-month period

    • You can enroll three months before your 65th birthday, your birthday month and three months after.
    • If you miss your initial enrollment period, you must wait until the next annual enrollment period, which usually takes place in the fall – your premiums may be higher if you wait.  
    • If you have a qualifying disability, you are eligible when you qualify for Parts A or B.
  5. Medigap – Six-month period

    • When you enroll in Part B, you are guaranteed the right to buy a Medigap policy for six months.
    • If you wait, your coverage may be limited based on your health history.