Scenario #1: 

Within 4 months of your Medicare eligibility date, ARE collecting Social Security benefits and wish to start Medicare Parts A and B when first eligible.?

If you are collecting Social Security four months prior to the first day of the month in which you turn 65, you will be automatically enrolled in Medicare Parts A and B.

You will receive your Medicare card in the mail approximately 110 days before the first day of the month in which you turn 65.

As an example, if you turn 65 on September 17, 2020, your Medicare eligibility begins on September 1, 2020. If you are collecting Social Security by May 1, 2020, you will receive your Medicare card around May 10, 2020 - 110 days before your Medicare effective date - showing Medicare Parts A and B with an effective date of September 1, 2020.

If for some reason you do not want to start Medicare Part B when you are first eligible - such as having health insurance through an employer - you can decline Medicare Part B by indicating on the enclosed form you wish to decline Medicare Part B and mail the form back to Medicare as instructed.

In this case, you will receive a new Medicare card showing that you have Medicare Part A only.

Scenario #4: 

Going to continue to have employer health insurance once you are eligible for Medicare - either through your or your spouse’s employer, ARE contributing to a Health Savings Account (HSA)?

IRS rules do not allow you to make tax-free contributions to an HSA if you have Medicare Part A.

Therefore, once again assuming you are not collecting Social Security, you should not enroll in any part of Medicare when you are approaching your Medicare Eligibility date.

You will be able to add Medicare Parts A And B later when you leave your employer coverage.

Scenario #5: 

Past your Medicare Eligibility Date but by less than 4 months and wish to go on full Medicare - Medicare Parts A and B - as soon as possible?

In this scenario you should follow the enrollment steps in Scenario #2 above.

However, your Medicare Part B effective date will be delayed past your original Medicare Eligibility Date due to your later enrollment.  For every month you delay enrolling in Medicare B past your Medicare Eligibility Date - up to three month, your Medicare Part B effective date will be delayed once month.

For example, if you enroll in Medicare Part B in the second month after your Medicare Eligibility Date, your Medicare Part B effective date will be the 1st day of the month 4 months after the month in which you turn 65.

In most cases your Medicare Part A effective date will still be your original Medicare Eligibility date.

Scenario #6: 

Past your Medicare Eligibility Date but by more than 4 months and ARE losing other health insurance coverage such as through an employer and wish to go on full Medicare - Medicare Parts A and B - when your current health coverage ends?

In this scenario you can enroll up to three months before your employer coverage ends.  

You will need to call or visit your local Social Security office as well as complete, sign and return CMS40B-E Medicare Part B Enrollment Form as well as have your employer complete, sign and return Employer Form CMS-L564E.

Your Medicare Part B will begin the 1st day of the month after your employer coverage ends or possibly the 1st of the month prior to when your employer coverage ends if needed to avoid a gap in coverage.  If you do not already have Medicare Part A, it will be placed in effect 6 months prior to your Medicare Part B effective date on a retroactive basis.

Scenario #7:

Past your Medicare Eligibility Date but by more than 4 months and ARE NOT losing other health insurance coverage such as through an employer and wish to go on full Medicare - Medicare Parts A and B - as soon as possible?

In this scenario you will need to use Medicare’s General Election Period to enroll in Medicare Part B as well as Medicare Part A if you do not already have Medicare Part A.

In Medicare’s General Election Period, you will need to visit your local Social Security office between the next January 1 and March 31 and complete the application for Medicare Part B and Medicare Part A if you do not already have Medicare Part A.

Your effective date for Medicare Part B will be the following July 1 and, in most cases, f you do not already have Medicare Part A, will be the preceding January 1 for Medicare Part A.

When Can I Enroll In A Medicare Supplement?

In most states you can enroll in a Medicare Supplement up to 6 months before your Medicare Eligibility Date.

When Can I Enroll In A Medicare Part D Drug Plan?

If you are first going on Medicare Part A, you can enroll in a Medicare Part D drug plan during a 7-month period that includes the three months before the month in which you turn 65 or become eligible for Medicare Part A, the month in which you turn 65 or become eligible for Medicare Part A and the 3 months after you turn 65 or become eligible for Medicare Part A.

When Can I Enroll In A Medicare Advantage Plan?

The timeline for enrolling in A Medicare Advantage plan is the same as the timeline for enrolling in a Medicare Part D drug plan. (see above section)