How to Sign Up for Medicare: Everything You Need to Know

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If your 65th birthday is approaching, it’s time to talk about Medicare.

You know it kicks in when you turn 65, but how does it work?

Some people are automatically enrolled while others need to sign up through the Social Security Administration.

You’ll also need to get coverage for prescription drugs and maybe a supplemental insurance policy.

It may seem confusing but once you know the steps, the enrollment process is pretty easy.

Here’s how signing up for Medicare works.

Do You Need to Sign Up for Medicare?

Everyone is eligible for Medicare at age 65. You can also get Medicare earlier if you have a long-term disability, end-stage renal disease or ALS (Lou Gehrig’s disease).

If you’re already receiving Social Security — either disability or retirement benefits — when you turn 65, you don’t need to sign up for Medicare Part A (hospital insurance) or Part B (outpatient coverage). You’ll be automatically enrolled.

You are automatically enrolled in Medicare Part A and Part B if: 

  1. You receive Social Security benefits or Railroad Retirement Board benefits for at least four months before turning 65.
  2. You are younger than 65 and have received Social Security disability benefits for at least 24 months.

Your coverage will begin the first day of the month you turn 65.

And that’s it! No further action is required on your part.

However, even if you’re automatically enrolled in Part A and Part B (known collectively as Original Medicare), there may still be other coverage you should sign up for, such as a Part D prescription drug plan or a Medigap supplement insurance policy.

We’ll cover how to sign up for those later.

Need a refresher on Medicare? Check out these seven frequently asked questions on how Medicare works.

How to Apply for Medicare If You’re Not Automatically Enrolled

If you haven’t claimed Social Security benefits yet and your 65th birthday is approaching, you need to sign up for Medicare on your own.

You have a seven-month window to sign up. It begins three months before you turn 65, includes your birthday month and extends three months after that. This timeframe is known as your initial enrollment period.

The fastest and easiest way to sign up for Medicare is to apply online through the Social Security Administration’s website.

It usually takes about 10 minutes to fill out the online application.

4 Steps to Enroll in Medicare Online

  1. Create a My Social Security account if you don’t have one already.
  2. Visit the Social Security Administration’s Apply for Benefits page.
  3. Click “Start a New Application.”
  4. Follow the instructions.

Here is a checklist of documents you should have on hand when you apply online, such as employment information.

You can also sign up for Medicare by calling Social Security at 800-772-1213 or by visiting a local Social Security office. However, both of these methods take much longer than applying online.

Sign Up for Medicare When You’re First Eligible

You should sign up for Medicare when you’re first eligible around your 65th birthday. Failing to do so can result in hefty late enrollment penalties and headaches later.

If you miss this initial enrollment period around your birthday, you can sign up during the general enrollment period which runs from Jan. 1 to March 31 each year.

As a note: The Social Security Administration handles Medicare enrollment. After that, you’ll receive your benefits from the U.S. Centers for Medicare & Medicaid Services, or CMS.

You can enroll in Medicare at age 65 without signing up for Social Security retirement benefits.

Do I Have to Sign Up for Medicare Part B?

The short answer? If you or your spouse are still working and you are covered under group health plan coverage through that current employment, you can choose not to enroll in Medicare Part B when you turn 65.

Here’s why.

Nearly everyone gets Medicare Part A for free (no monthly premiums). That’s because you paid into the program, which covers hospital insurance, via payroll taxes when you were working.

Because you’re required to pay a monthly premium for Part B outpatient coverage, the Social Security Administration gives you the option to turn it down.

But let’s be clear: Unless you’re still working and covered under a qualifying group health plan at work, you should absolutely sign up for Medicare Part A and Part B at the same time when you’re first eligible around your 65th birthday.

Failing to do so can jack up your Medicare premiums for the rest of your life.

In fact, your monthly Part B premium will go up 10% for each 12-month period you were eligible for coverage but didn’t sign up.

If you decide to delay Part B because you’re still working, you can sign up for the coverage later. If you lose your job or your health insurance plan at work, you’ll get an eight-month special enrollment period to sign up for Part B coverage after your workplace coverage ends.

Trying to save money on things like eyeglasses, hearing aids or dental work? Our money-saving Medicare guides have you covered.

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I Applied For Medicare Coverage: Now What?

Once you submit your online application, ​​you’ll receive a number you can use to check on the status of your Medicare application.

About two to three weeks after you sign up, you’ll also receive a Medicare welcome packet in the mail. It includes your red, white and blue Medicare card along with your Medicare & Me handbook.

When your coverage actually begins depends on when you signed up.

If You Were Automatically Enrolled in Medicare

If you’re already receiving Social Security benefits, you’ll automatically get Medicare Parts A and B.

Your Medicare coverage starts the first day of your birth month.

If your birthday is on the first of the month, your coverage kicks in on the first day of the prior month. (If your birthday is Sept. 1, for example, your coverage begins Aug. 1.)

If You Aren’t Automatically Enrolled In Medicare

Starting Jan. 1, 2023, if you sign up during your birthday month or during the following three months, your coverage begins the first day of the month after you sign up.

Let’s say your birthday is Sept. 14 and you sign up for Medicare on Sept. 7. Your coverage will begin Oct. 1. If your birthday is Sept. 14 and you sign up Oct. 13, your coverage starts Nov. 1.


When Your Medicare Coverage Becomes Effective

If You Sign Up … Your Medicare Benefits Begin:

1-3 months before you turn 65

The month you turn 65

The month you turn 65 or 1-3 months after that

The first day of the month after you sign up

How to Sign Up for Medicare Part D and Medigap Supplemental Insurance

You’re officially enrolled in Original Medicare — congrats!

But your work isn’t over yet.

You’ll need Medicare prescription drug coverage and possibly a supplement insurance plan to help fill in coverage gaps.

The Medicare Plan Finder tool is the fastest and easiest way to sign up for a Medicare Part D plan or Medigap policy.

How To Sign Up For A Medicare Part D Or Medigap Plan Online:

  1. Enter your zip code and the plan type (Part D plans, Medigap plans, etc.) into the Medicare Plan Finder.
  2.  Browse available plans as a guest. Or, if you want to save your progress, sign up for a free MyMedicare.gov account.
  3. You’ll see a list of plans in your area, along with costs and coverage details.
  4. Carefully review the pros and cons of each plan so you get the best value for your health care needs.
  5. You can enroll in a plan by clicking the “Enroll” button next to the plan’s name.

To sign up for additional coverage, you’ll need your Medicare number and the date your Part A and Part B coverage started. Check your Medicare card or login to your MyMedicare.gov account to find this info.

Medicare Part D coverage is technically optional if you’re enrolled in Original Medicare, but you’ll face stiff penalties if you skip it now and try to sign up for it later.

Medigap plans are optional but enrolling in one can help cover your out-of-pocket costs, like deductibles and copays at the doctor’s office. You get a six-month window after starting Part B to select a Medigap policy without any medical underwriting.

Comparing Part D or Medicare supplement insurance plans can be confusing. Thankfully, you can call your local State Health Insurance Assistance Program (SHIP) for free assistance.

Trying to save money on prescription drugs in retirement? Here are six hacks to help lower costs.

How to Sign Up for a Medicare Advantage Plan

You can also use the Medicare Plan Finder tool to sign up for a Medicare Advantage plan.

You’ll follow the same steps to find a plan: Enter your zip code, review plans in your area and enroll in one that meets your needs.

What Is Medicare Advantage?

Medicare Advantage plans are administered by private insurance companies that contract with the federal government.

When you sign up for Medicare, you can stick with your Original Medicare coverage or you can choose to get all your benefits bundled together in a Medicare Advantage plan instead.

Medicare Advantage plans must offer the same basic coverage as Original Medicare but they may also offer other benefits, such as vision and dental coverage. Nearly all Medicare Advantage plans also include prescription drug coverage.

You can either have Original Medicare or Medicare Advantage. You can’t have both.

You also can’t sign up for a standalone Part D plan or a Medigap policy if you’re enrolled in a Medicare Advantage plan.

However, you must be enrolled in Medicare Parts A and B before you can switch to a Medicare Advantage plan.

Rachel Christian is a Certified Educator in Personal Finance and a senior writer for The Penny Hoarder.