When does my Initial Enrollment Period start?

Your Initial Enrollment Period (IEP) is a 7-month window: it begins 3 months before the month you turn 65, includes your birthday month, and ends 3 months after. Coverage starts on the first day of the month you turn 65 if you sign up during the 3 months before your birthday.

Do I have to sign up for Medicare at 65?

Not always. If you (or a spouse) are still working and have qualifying group coverage from a large employer (generally 20+ employees), you can usually delay Part B without a penalty until that coverage ends. If your employer plan is smaller than 20 people, Medicare typically becomes your primary insurance and you should enroll at 65 to avoid coverage gaps. Talk to a licensed agent if you're not sure how your situation maps to the rules.

Do I have to do anything if I already get Social Security?

If you're already collecting Social Security retirement benefits when you turn 65, you're usually enrolled in Medicare Parts A and B automatically. You'll receive your red, white, and blue Medicare card in the mail about 3 months before your 65th birthday. You still need to decide whether to add Medicare Advantage, a Medicare Supplement, and/or a Part D drug plan.

What happens if I miss my IEP?

You may have to wait for the General Enrollment Period (January 1 to March 31 each year) to sign up for Part B, with coverage starting the month after enrollment. Late enrollment in Part B can result in a permanent monthly penalty added to your premium for as long as you have Medicare, so it's best to act during your IEP.

Should I keep my employer plan or switch to Medicare?

It depends on the plan's size, cost, and benefits. Some employer plans coordinate well with Medicare; others become redundant or even more expensive once Medicare kicks in. A licensed Medicare agent can compare your current benefits against Medicare options at no cost. Get a free comparison before making the switch.

Turning 65: What to Do for Medicare

The 7-month window: your Initial Enrollment Period

Most people first become eligible for Medicare when they turn 65. Your Initial Enrollment Period (IEP) is a 7-month window centered on your birthday month:

3 months before the month you turn 65
The month you turn 65
3 months after the month you turn 65

If you sign up in the 3 months before your birthday month, your coverage starts the first day of the month you turn 65. If you wait until your birthday month or later, coverage starts later (sometimes up to 3 months after you sign up.

Are you enrolled automatically?

If you're already collecting Social Security retirement benefits at 65, you're typically enrolled in Original Medicare (Parts A and B) automatically. Your red, white, and blue Medicare card will arrive in the mail about 3 months before your 65th birthday.

If you're not yet collecting Social Security, for example, you're delaying benefits to a later age, you need to actively enroll. You can do this online at ssa.gov/medicare, by phone at 1-800-772-1213, or at your local Social Security office.

Still working with employer coverage?

The rules depend on the size of the employer:

Large employer (generally 20+ employees): You can usually keep your employer coverage as primary and delay enrolling in Part B without a late-enrollment penalty. When the coverage ends, you have a Special Enrollment Period to sign up for Part B.
Small employer (fewer than 20 employees): Medicare typically becomes your primary insurance at 65, and your employer coverage becomes secondary. Most people in this situation should enroll in Parts A and B during their IEP to avoid coverage gaps.

If you're on a high-deductible health plan with an HSA, signing up for any part of Medicare (including Part A) means you can no longer contribute to the HSA. Plan the timing carefully.

Decide what to do beyond Original Medicare

Parts A and B (Original Medicare) cover hospital and medical care, but they don't include prescription drugs, dental, vision, hearing, or an out-of-pocket maximum. Most people add one of these two paths:

Medicare Advantage (Part C): an all-in-one private plan that bundles A, B, and usually D, often with extras like dental and vision. Learn how Medicare Advantage works.
Medicare Supplement (Medigap) + a standalone Part D plan, Medigap helps cover what Original Medicare doesn't (deductibles, coinsurance), and Part D covers prescriptions. Learn how Medicare Supplement plans work.

We can walk you through both routes based on your doctors, prescriptions, travel habits, and budget. See our Medicare Advantage vs. Medicare Supplement comparison for a deeper dive.

Avoid the late-enrollment penalties

Late-enrollment penalties for Medicare are permanent. They get added to your monthly premium for as long as you have Medicare. The biggest ones to watch:

Part B penalty: If you don't enroll when first eligible and don't have other qualifying coverage, the Part B premium goes up by 10% for each full 12-month period you could have had it but didn't.
Part D penalty: Going 63+ days without creditable prescription drug coverage adds 1% of the national base beneficiary premium for each month you went without. Also permanent.

The simple way to avoid both: enroll during your IEP, or maintain credible employer coverage and then enroll during your Special Enrollment Period when it ends.

Your 65-and-Medicare checklist

4-6 months before 65: Decide whether you'll stay on employer coverage or move to Medicare. If moving to Medicare, request quotes for Medicare Advantage and Medigap.
3 months before 65 (IEP opens): Enroll in Parts A and B (or confirm auto-enrollment via Social Security).
2-3 months before 65: Pick a Medicare Advantage planor a Medigap policy + standalone Part D plan. Verify your doctors and prescriptions are covered.
First of the month you turn 65: Coverage begins (assuming you signed up during the 3 months prior).
Every year after, October 15 to December 7: Annual Enrollment Period, review your plan and switch if needed.

Still not sure where you fall? Talk to a licensed Medicare agent. There's no cost to you, and the comparison takes a few minutes.

Turning 65? Here's exactly what to do for Medicare.