When Is It Time to Enroll in Medicare?

medicare enrollment form

As you begin to approach your 65th birthday, the most important thing you can do is invest some time to understand the complexities, nuances, deadlines and coverage options related to Medicare.

Your Medicare Initial Enrollment Period begins 90 days prior to the first day of your 65th birthday month and runs for seven months. If you enroll during the three months prior to your birthday month, Medicare will become effective on the first day of your birthday month. That is the most preferable scenario. The easiest way to enroll in Medicare is to go online to www.ssa.gov. If that is not an option you can alternatively visit your local Social Security Administration office or call the SSA at 800-772-1213.

Before you enroll, however, you will need to know whether to enroll in both Part A (hospital) and Part B (medical), or to enroll in Part A and delay enrollment in Part B. That decision will be based on a number of factors, such as whether you plan to continue working, and the type of health insurance you currently have.

When you are age 65 or older and covered by a group health plan through your current employer or your spouse’s current employer, the total number of employees who work for the business/organization sponsoring that group health plan determines which health insurance pays first on a claim — Medicare or the group health plan. If the employer sponsoring the group health plan has 20 or more employees, the group health plan pays first, or is “primary,” and Medicare is a “secondary” payer. If you fall into this category it may be advantageous for you to “delay” enrollment in Part B until you stop working and/or are no longer covered by the group health plan.

If you are covered by a group health plan offered by an employer with fewer than 20 employees, Medicare pays first or is “primary,” and the group health plan is “secondary.” In that case you need to enroll in both Part A and Part B of Medicare. Additionally, if you are covered by an individual health plan, COBRA, or a retiree health plan but are no longer “actively working,” then you will also need to enroll in both Part A and Part B.