Step 1: Know Your Initial Enrollment Period
Your Initial Enrollment Period (IEP) is a 7-month window: 3 months before the month you turn 65, your birthday month, and 3 months after. Enrolling in the first 3 months typically starts coverage the month you turn 65; waiting until later in the window can delay your start date.
Step 2: Decide How to Enroll
If you're already receiving Social Security benefits, you're usually enrolled in Part A and Part B automatically. If not, you'll need to actively sign up through the Social Security Administration — online at ssa.gov, by phone, or in person.
Step 3: Choose Original Medicare or Medicare Advantage
Once enrolled in Part A and B, decide whether to stay on Original Medicare (adding a separate Part D drug plan and optionally a Medigap supplement) or switch to a Medicare Advantage plan that bundles everything through a private insurer.
Step 4: Add Part D Drug Coverage
If you don't enroll in a Medicare Advantage plan with drug coverage built in, you need a standalone Part D plan. Enroll during your Initial Enrollment Period even if you don't take medications currently — delaying without other creditable drug coverage triggers a permanent late-enrollment penalty.
Step 5: Consider a Medigap Plan
If you choose Original Medicare, your best window to buy a Medigap policy is the 6-month Medigap Open Enrollment Period that starts the month you're 65 and enrolled in Part B. During this window, insurers must sell you a policy regardless of health conditions. Miss it, and you may face medical underwriting or denial later.
What If You're Still Working Past 65?
If you have employer coverage through a large employer (20+ employees) when you turn 65, you can often delay Part B without penalty until that coverage ends, then you get an 8-month Special Enrollment Period to sign up. Confirm with your employer's benefits office whether your specific coverage qualifies as creditable before delaying enrollment.
Key Enrollment Deadlines to Remember
- Initial Enrollment Period: 7 months around your 65th birthday
- Annual Enrollment Period: October 15 – December 7, for switching Advantage/Part D plans
- Medicare Advantage Open Enrollment Period: January 1 – March 31, for those already enrolled in Advantage
- General Enrollment Period: January 1 – March 31, for those who missed their Initial Enrollment Period entirely
Frequently Asked Questions
You can enroll during the General Enrollment Period (January 1–March 31), but you may face a permanent Part B late-enrollment penalty of 10% for each 12-month period you were eligible but didn't enroll, unless you qualify for a Special Enrollment Period through employer coverage.
No — once enrolled in Part A and B, you're covered indefinitely. You only need to actively make changes during Annual Enrollment if you want to switch your Advantage or Part D plan.
Yes — you can apply for Part A and Part B directly through the Social Security Administration's website at ssa.gov, or by phone or in person at a local Social Security office.