Turning 65: Your complete guide to starting Medicare

When you become eligible

Most people become eligible for Medicare at 65 whether or not they have retired, and this page is part of our Medicare 101 series on how to sign up for Medicare and what comes next. You can qualify earlier through 24 months of Social Security Disability Insurance, or immediately with end-stage renal disease or ALS. One thing that trips people up: Medicare age and Social Security age are not the same. Full retirement age for Social Security is 67 for anyone born in 1960 or later, but Medicare still starts at 65, and you can take Medicare while leaving your retirement benefits to grow.

Your 7-month Initial Enrollment Period

Your Initial Enrollment Period opens 3 months before the month you turn 65, includes that month, and closes 3 months after it. When your coverage actually begins depends on where in that window you sign up, which is the part people miss.

• Sign up in the 3 months BEFORE: Coverage usually starts on the first day of your birthday month. This is the clean option.
• Sign up during your birthday month or later: Coverage starts the first day of the month after you sign up, leaving a gap.
• So enroll early in the window: There is no advantage to waiting, and a real cost to it.

Will you be signed up automatically?

It depends entirely on whether you are already collecting benefits. If you receive Social Security or Railroad Retirement benefits at least 4 months before turning 65, you are enrolled in Parts A and B automatically and your Medicare card arrives about 3 months ahead of your birthday. You can keep Part B or follow the card's instructions to decline it, which makes sense if you have qualifying coverage through current work. If you are not collecting benefits yet, nothing happens on its own and you have to apply.

• Online at ssa.gov: Usually under half an hour, and the fastest route.
• By phone: Social Security on 1-800-772-1213.
• In person: Your local Social Security office. Book ahead rather than walking in.
• Railroad Retirement Board: If you worked for a railroad, apply through them instead.

What to have ready before you apply

Applying is free. Nobody should charge you to file it, and you should not pay anyone who offers. Have your Social Security number, your date and place of birth, your current health coverage details, and the dates any job-based coverage started or ends. If you or your spouse is still working, ask the employer for written proof of the group coverage now, because you may need it later to show you were entitled to wait. Keep copies and the confirmation number. Most applications clear within a few weeks and you can track yours in an online account with Social Security.

The Parts of Medicare, in one minute

The Parts of Medicare come down to two to begin with. Original Medicare is run by the federal government: Part A is hospital insurance, covering inpatient stays, skilled nursing, hospice and some home health care. Part B is medical insurance, covering doctor visits, outpatient care, lab tests and preventive services. Most people get Part A with no premium because they or a spouse paid Medicare taxes for at least 10 years; if not, you can buy it, from $311 to $565 a month depending on your quarters. Part B charges almost everyone a monthly premium, $202.90 as the 2026 standard amount, and higher earners pay more on top through IRMAA.

Your two coverage paths

Once you have Parts A and B, you decide how to cover what they do not. There are two routes and you cannot combine them, so this is the real decision of the year. Compare them on our Medicare Advantage and Medicare Supplement pages, and look at drug plans on our Part D page.

• Original Medicare plus extras: Keep Parts A and B, add a Part D drug plan, and add a Medigap policy to help with deductibles and coinsurance. Any doctor who accepts Medicare, no networks.
• Medicare Advantage (Part C): A private plan that delivers your Parts A and B benefits, usually with drug coverage and extras included. Lower premiums, but provider networks apply.
• Your Medigap window opens once: 6 months from the first month you are 65 and have Part B. Inside it no insurer can refuse you or charge more for your health. Afterwards, in most states, they can.

If you are still working at 65

You may be able to delay Part B without any penalty, and the deciding factor is which insurer pays first. If your employer has 20 or more employees, the group plan usually pays first and many people wait. If it has fewer than 20, Medicare usually pays first, so you generally need Part B at 65 even though you are still covered at work. When the job or the coverage ends you get an 8-month Special Enrollment Period for Part B. COBRA and retiree plans do not count as coverage from current work and do not extend that window. Our working past 65 guide covers the employer-size rule in detail.

The deadline most people miss

Miss your Initial Enrollment Period without qualifying for a Special Enrollment Period and your next chance is the General Enrollment Period, January 1 to March 31, with coverage starting the month after you sign up. That can mean months uninsured plus a permanent late enrollment penalty. The Part B version is 10% of the standard premium for every full 12-month period you could have had it, and you pay it for as long as you have Part B. Part D runs its own clock: 63 days or more without creditable drug coverage after your window and a penalty is added to that premium too.

The windows that matter after you enroll

Enrollment Periods After You Sign Up matter just as much as the first one, because plans change their costs, networks and drug lists every year. Three windows recur.

• October 15 to December 7: Medicare Open Enrollment. Change your Medicare Advantage or drug plan for January 1.
• January 1 to March 31: Medicare Advantage Open Enrollment. If you are in a plan, switch once or go back to Original Medicare.
• Special Enrollment Periods: Opened by events like moving or losing other coverage.

Coming to Medicare before 65

Not everyone starting Medicare is turning 65. After 24 months of disability benefits you are enrolled automatically and the card arrives before coverage begins. With ALS, enrollment is automatic from the first month of disability benefits, with no waiting period at all. End-stage renal disease works differently: you must apply yourself, and coverage usually begins in the fourth month of dialysis, or earlier if you train for home dialysis or have a transplant. If you already have Medicare through disability, it simply continues at 65, and importantly you get a fresh Medigap open enrollment window with full protections at that point.

Help with the costs

If your income is limited, look at help paying Medicare costs before you choose a plan rather than after. Medicaid, a Medicare Savings Program and Extra Help all reduce what you pay, and the first of those can cover your Part B premium outright. Extra Help income limits are $23,475 for an individual and $31,725 for a couple.

Your turning-65 timeline

Give yourself runway. This keeps you out of penalty territory and leaves time to compare plans properly instead of rushing a decision you live with for a year.

• 6 months before: Decide whether you will still be working and covered by a group plan, and check how many employees it has.
• 3 months before: Your window opens. Sign up, or confirm your automatic enrollment.
• Watch for your card: It arrives around 3 months before coverage starts. Keep it somewhere safe.
• Choose your path: Original Medicare with Part D and Medigap, or a Medicare Advantage plan.
• Mark the penalty dates: Note when your window closes and the 63-day drug coverage rule.
• Get free help if you want it: Your State Health Insurance Assistance Program gives unbiased counseling at no cost.

Common questions

More in Medicare 101

• Medicare Eligibility: Who Qualifies, and When
• How to Enroll in Medicare, Step by Step
• Medicare and Working Past 65: When to Enroll and What to Keep
• The Parts of Medicare, Explained: A, B, C and D
• Medicare Enrollment Periods: Every Window Explained
• Medicare Late Enrollment Penalties, and How to Avoid Them
• Medicare Costs: What You'll Actually Pay
• Medicare Advantage vs. Medicare Supplement: How to Choose
• Medicare Prescription Drug Coverage: Where It Comes From and How It Works