Your Medicare enrollment typically begins with the Initial Enrollment Period (IEP), a seven-month window around your 65th birthday.

The Initial Enrollment Period starts three months before the month you turn 65, includes your birthday month, and ends three months after. Missing this window can lead to a late enrollment penalty for Part B and Part D. If you have health insurance through your current employer when you turn 65, you may be able to delay enrollment without penalty.

Enrollment rules can be complex, and individual circumstances vary, so it's important to confirm your specific situation.