How to Sign Up for Medicare

Navigating Medicare enrollment can be confusing. Here’s how to find out if you are eligible for Medicare and when you are able to enroll.

Older man seated while typing on a portable computer in his lap

The Medicare enrollment process can be incredibly confusing. Eligibility guidelines are set by the federal government, but you are not automatically enrolled in Medicare once you reach a certain age. Here’s what you need to know about how to sign up for Medicare and what all the different parts are for.

How to Apply for Medicare

You can apply for Medicare plans in the following ways:

  • Visit your local Social Security office
  • Call the Social Security Administration at 1-800-772-1213
  • Apply by mail by sending a signed and dated letter with your name, Social Security number, and date you would like enrollment to start
  • Apply online at

Remember to note the names of representatives you spoke to, use certified mail for documents submitted, and save your confirmation page if you enrolled online. Proof of your application will waive Part B penalties if your application is lost or delayed.

Am I Eligible for Medicare?

Generally, you can sign up for Medicare when you are age 65 or older. However, younger people who receive Social Security disability benefits (SSDI) also are automatically enrolled in Medicare 24 months after their first benefit payment.

Regardless of age, people who have ALS (Lou Gehrig’s Disease) are automatically enrolled in Medicare once they receive their first disability benefits payment. People with end-stage renal disease (kidney failure) also can sign up with Medicare, with coverage usually commencing after four months of dialysis treatment. Some kidney failure patients may receive retroactive coverage for a maximum of 12 months. In some cases, the four-month waiting period can be waived.

Medicare coverage can begin as early as the first month of a regular course of dialysis treatments if you meet all of these conditions:

  • You participate in a home dialysis training program offered by a Medicare-certified training facility during the first 3 months of your regular course of dialysis.
  • Your doctor expects you to finish training and be able to do your own dialysis treatments at home.
  • You maintain a regular course of dialysis throughout the waiting period that would otherwise apply.

When Can You Apply for Medicare?

For people age 65 and older, Medicare enrollment is not automatic unless you are disabled, have ALS, or have end-stage renal disease and meet those conditions for automatic enrollment. Signing up for Medicare in anticipation of your 65th birthday is referred to as your initial enrollment period. It is recommended that you sign up for Medicare three months before your 65th birthday to ensure your coverage will start on the first day of your birthday month. 

Most people have seven months around their 65th birthday to enroll: three months before their birthday month, the birthday month, and three months after. If you were born the first day of that month, the coverage begins the first day of the prior month, making your initial enrollment period technically four months prior to your birthday month and two months after.

Other opportunities to enroll are the Open Enrollment Period, Annual Enrollment Period and Special Enrollment Periods. 

The Open Enrollment Period (OEP) runs from January 1-March 31 and is for people currently enrolled in a Medicare Advantage plan. Its main purpose is to allow Medicare Advantage members to make a one-time switch back to original Medicare or a different Medicare Advantage plan, with the new coverage beginning on the first day of the month following the switch.

The Medicare Annual Enrollment Period (AEP) runs from October 15-December 7, with new coverage going into effect on January 1 of the following year. Available options depend on the type of coverage you already have, such as joining a Medicare Advantage plan or switching to a plan with or without built-in drug coverage.

Special Enrollment Periods (SEP) for Medicare occur based on certain life events, such as moving or losing your current health coverage. Dual eligibility for Medicare and Medicaid also triggers a SEP. Timeframes for enrolling in Medicare after the event will vary, but you usually have two months to apply in most cases such as moving back to the United States after living abroad or departing a skilled nursing facility.

Medicare Parts 

Medicare consists of four parts. Most people enroll in Parts A and B, known as Original Medicare, simultaneously, but may delay Part B if they still have employer-sponsored healthcare.

Medicare Part A

Medicare Part A covers in-patient hospital care, skilled nursing facility short-term care, hospice care, and home health services. It has no premiums if you or your spouse paid Medicare taxes from working at least 10 years, but can be purchased if you are not eligible for premium-free coverage.

Medicare Part B

Medicare Part B covers doctor visits, durable medical equipment, preventive care, and other outpatient care. It has a premium that varies by income. 

Medicare Part C

Medicare Advantage is called Medicare Part C but is a private plan that includes the benefits offered in Parts A and B with coinsurance responsibilities. You must be enrolled in Parts A and B to be eligible for a Medicare Part C plan (Medicare Advantage).Medicare Part C takes the place of Parts A and B and includes the following benefits:  

  • Hearing care for hearing aids and tests 
  • Vision care for glasses and contacts 
  • Dental care for routine exams and x-rays 
  • Fitness and wellness programs  
  • No premiums or deductibles on many plans

Out-of-pocket costs will be capped for any Part C covered services through all Medicare Advantage plans. This means that once you reach that cap, you will not have to pay anything else for the rest of the year.  

Another feature of getting a Part C plan is that it can either include or exclude Part D depending on your needs.  

Medicare Part D

Medicare Part D is prescription drug coverage offered by government-approved private insurers. Premiums are based on the location of your primary residence when you enroll. There are many Part D plans to choose from, with varying levels of copayments and coverage. The types of drugs that are covered may also vary from plan to plan. Many Medicare Advantage plans include Part D coverage, which makes purchasing a separate Part D plan unnecessary. 

Penalties for Late Medicare Enrollment

If you don’t apply for Medicare in enough time around your 65th birthday, there are steep late penalties for each part:

Part A

If you don’t buy into Part A during your initial enrollment period, the penalty is 10% of the monthly premium for twice the timeframe you didn’t sign up with Medicare. For instance, if you were eligible for Part A for two years but did not enroll, you will need to pay a higher premium for four years with this 10% penalty.

Part B

If you don’t sign up within your eligibility window, Part B premiums will permanently increase 10% for each 12-month period you lacked Part B coverage.

If you waited two years to sign up for part B, you have a 20% late enrollment penalty (based on 10% for each full year you could have enrolled) in addition to the standard Part B monthly premium, which is $164.90 in 2023. With 20% of $164.90 being $32.98, your higher Part B premium is $197.90 since Medicare rounds to the nearest $0.10.

Part D

If you don’t have drug coverage for 63 days or longer after the initial enrollment period, Part D also carries a permanent premium that is recalculated annually, based on 1% of the national base beneficiary premium ($32.74 in 2023) and the number of months you were not covered. For instance, if you signed up for Medicare in mid-July 2020 but had not bought into Part D by July 31, 2020, the monthly penalty is calculated based on the ensuing months without creditable prescription drug coverage. If you signed up for a prescription drug plan in December 2022 during the open enrollment period and commence coverage in January 2023, this makes the Part D penalty 29% for the 29 months between August 2020 and December 2023.

With a national base beneficiary premium of $32.74, 29% comes to $9.49 which is rounded to $9.50 based on Medicare’s nearest $0.10 rounding convention. This penalty must be paid in perpetuity in addition to the base premium, and it has no cap.

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Contact us any time and a Baylor Scott & White Health Plan licensed insurance agent can answer any questions you have about Medicare.