Most people have enrolled automatically in Original Medicare (Part A and Part B) as they approach the age of 65 with coverage start dates based on birthday month. For those who need to enroll manually, effective coverage dates could be earlier or later, depending on the situation. Knowing exactly when your coverage starts can help you make the right decisions about your medical care.
Automatic Enrollment
Here’s the good news: most people have enrolled in Original Medicare automatically, and receive a red, white, and blue Medicare card by mail approximately 3 months before turning 65. In this case, Medicare benefits begin on the first day of your birthday month. For example, if you were born on July 24, July 18, or even July 31, your benefits begin on July 1. There is one exception. For those born on the 1st of the month, benefits begin on the 1st day of the month before the birthday month. For example, if you were born on December 1, your benefits begin on November 1.
If You Sign Up Manually During Your Initial Enrollment
In the event you have not enrolled automatically and choose to enroll in Medicare yourself, effective coverage dates vary based on the month you sign up. If you sign up during your Initial Enrollment Period (the 7 months beginning 3 months before your 65th birthday and ending 3 months after your 65th birthday) effective start dates are shown below.
If you sign up for Medicare:
The same month you turn 65, coverage begins 1 month after you sign up.
1 month after you turn 65, coverage begins 2 months after you sign up.
2 months after you turn 65, coverage begins 3 months after you sign up.
3 months after you turn 65, coverage begins 3 months after you sign up.
If You Sign Up Manually After Your Initial Enrollment Period
You may enroll in premium-free Part A (most people are eligible) anytime during or after your Initial Enrollment Period starts with coverage start dates based on when you sign up. However, if you do not qualify for free Part A, and need to buy it or need to sign up for Part B, and miss your Initial Enrollment Period, you may have to wait until General Enrollment Period, Jan 1-Mar 31, with coverage starting on July 1.
References:
https://www.medicare.gov/sign-up-change-plans/get-parts-a-and-b/when-coverage-starts/when-coverage-starts.html
https://www.medicare.gov/sign-up-change-plans/get-parts-a-and-b/when-how-to-sign-up-for-part-a-and-part-b.html#collapse-5769
https://www.medicare.gov/sign-up-change-plans/get-parts-a-and-b/when-sign-up-parts-a-and-b/when-sign-up-parts-a-and-html
https://www.medicare.gov/your-medicare-costs/part-a-costs/part-a-costs.html
MUC64-2017-BCBS
