Most people will be automatically enrolled in Medicare Part A and Part B at age 65. You can delay your enrollment in Part B if you wish but this should only be done if you have other creditable coverage such as through an employer group health plan.
Postponing Part B without creditable coverage could create a late enrollment penalty.
You can delay enrolling in both Medicare Part B and Part D if you continue to work and are covered under your employer's group health plan. You can also delay enrolling in Medicare Part B and D if you are covered under your spouse's group health plan through his or her employer. I would check with your employer before you decide to delay enrolling in Medicare. Go ahead and enroll in Part A of Medicare because it is free.
Postponing Part B without creditable coverage could create a late enrollment penalty.