Enrolling in Medicare should be at the top of your to-do list if you’re approaching age 65, but how you enroll depends on one factor: When you begin collecting Social Security or Railroad Retirement Board benefits. If you begin collecting these benefits at age 65 (or earlier), you are automatically enrolled in Medicare, making the process relatively seamless. If you decide to delay Social Security to increase your retirement benefits, you must actively sign up for Medicare on your own. Failing to do so on time may result in late enrollment penalties, higher monthly premiums and delayed access to important health coverage.
[READ: Navigating Medicare Deductibles and Premiums in 2026]
Your Step-by-Step Guide to Enrolling in Medicare
To simplify your Medicare enrollment process, follow these eight steps.
1. Check your Medicare eligibility
Medicare is available to older Americans, but there are special circumstances in which younger individuals may also qualify.
The general eligibility requirements for Medicare include:
— You are age 65 and older.
— You are a younger individual with a specific disability, end-stage renal disease or ALS (amyotrophic lateral sclerosis).
— You are a U.S. citizen or legal permanent resident who has lived in the United States for at least five continuous years.
[SEE: Preventing Costly Medicare Mistakes: Tips and Strategies]
2. Know your enrollment windows
First-time Medicare enrollees must sign up during the initial enrollment period, which is a seven-month period that typically starts three months before your 65th birthday, extends through your birth month and ends three months after it.
“If you are proactively signing up to begin Medicare at age 65, if possible, submit the application three months before your birthday month,” advises Marcia Mantell of Mantell Retirement Consulting in Plymouth, Massachusetts. “When you apply for Medicare determines when your coverage begins. Coverage only begins on time if you apply before your birthday month.”
Other times you can sign up for Medicare include:
| Enrollment Period | Who It’s For | When | What You Can Do |
| Annual enrollment period | Anyone with Medicare | October 15 — December 7 | Sign up, switch or drop a Medicare Advantage or Part D plan for the next year |
| General enrollment period | People who missed their initial enrollment and don’t qualify for a special enrollment period | January 1 — March 31 | Sign up for original Medicare, but late penalties may apply |
| Medicare Advantage open enrollment period | Anyone with a Medicare Advantage plan | January 1 — March 31 | Switch to another Medicare Advantage plan or return to original Medicare |
| Special enrollment period | People delaying Medicare due to employer coverage or certain qualifying life events | Varies | Sign up for original Medicare or a Medicare Advantage plan |
[READ: Medicare Advantage Initial Enrollment Period and Special Enrollment Periods]
3. Understand the parts of Medicare (A, B, C and D)
When you enroll in Medicare, you’ll need to become familiar with the different parts of the program.
Here’s a simple breakdown of those parts and the typical costs that come with each:
| Medicare Part | What It Covers | Monthly Premium and Deductible | Copay / Coinsurance | Out-of-Pocket Maximum |
| Part A (hospital insurance) | Inpatient hospital stays, skilled nursing facility (SNF) care, hospice and some home healthcare | Premium: $0 for most people (up to $565 per month if not premium-free)
Deductible: $1,736 per benefit period |
Daily coinsurance for extended hospital stays and SNF care after day 20 | No annual out-of-pocket maximum |
| Part B (medical insurance) | Doctors’ services, outpatient care, some home health services, durable medical equipment, mental health services and other medical services | Premium: $202.90 per month
Deductible: $283 per year |
Typically 20% coinsurance after deductible | No annual out-of-pocket maximum |
| Part C (Medicare Advantage) | All of the benefits and services covered under Part A and Part B, plus additional benefits, such as vision, dental and hearing care, and drug coverage, depending on the plan | Premium: Varies by plan, but some have a $0 premium; Part B premium still required
Deductible: Varies by plan |
Varies by plan | Up to $9,250 in-network; up to $13,900 out-of-network |
| Part D | The cost of prescription drugs | Premium: Varies by plan
Deductible: Up to $615 (some plans have a $0 deductible) |
Copays or coinsurance based on drug tier | $2,100 annual cap on covered drugs |
4. Gather your required documents
To enroll in Medicare, you will need to provide information to the government to prove that you qualify. It’s important to note that the specific documents required may vary depending on your individual circumstances.
According to the Social Security Administration, common necessary documents and information include:
— Your Social Security number
— Your city of birth
— Your current health insurance
Further information, such as disability documentation if you are under 65, may be requested during the application process.
5. Submit your application
You can enroll in Medicare:
— Applying online through the Social Security Administration’s website
— Calling 1-800-772-1213
— Visiting a local Social Security office in person. The “Find an Office” tool can help you locate the nearest office.
6. Choose supplemental coverage (Medicare Advantage, Medigap or Part D)
If you sign up for Medicare parts A and B and decide to stick with original Medicare, you should also consider enrolling in a Medigap plan, which can help cover the remaining 20% coinsurance costs, or a Part D plan for medication coverage, Mantell says. If you are looking for further coverage, a Medicare Advantage plan, which is offered by private insurers, may be a better fit.
You should apply for those parts in the month just prior to your 65th birthday.
“You must have your Medicare number already established and your Part B effective date locked in,” Mantell says. “Timing really matters to get all of your coverages starting on the same day.”
If you want to buy Medigap after your initial enrollment period, you may face medical underwriting, which means your coverage may cost more or be denied.
7. Look for your red, white and blue card
A few weeks after submitting your application, you should receive a Medicare card in the mail that will include your name and Medicare number. Protect and keep this card safe to ensure no one steals your Medicare number.
You can check the status of your application by:
— Logging into your account
— Calling the customer service number (1-800-772-1213)
— Visiting your local office
8. Review your plan annually
Each fall, your provider will send you an Annual Notice of Change to let you know how coverage, costs or service areas may be different starting in January. Take note of these changes, and make sure to account for any anticipated health needs you’ll have.
More from U.S. News
How to Avoid Paying a Medicare Late Enrollment Penalty
Does Medicare Cover Ambulance Services and Emergency Medical Care?
What to Look for in a Good Medicare Dental Plan
How Do You Apply for Medicare? originally appeared on usnews.com
Update 06/24/26: This story was published at an earlier date and has been updated with new information.
