How to Enroll in Medicare Online: Step-by-Step Guide
Reviewed October 4, 2026. You can enroll in Medicare Part A and Part B online through Social Security at ssa.gov/benefits/medicare. The application normally takes 10 to 30 minutes, you can submit it up to three months before you turn 65, and there’s nothing to sign or mail (SSA). If you already get Social Security benefits, you’re usually enrolled automatically and don’t need to apply.
Quick answer: Go to SSA.gov, choose to apply for Medicare only (or Medicare plus retirement benefits), answer the questions, and select “Submit Now.” Save your confirmation number and track the application in your my Social Security account. Once you have Part A and Part B, you can join a Medicare Advantage or Part D plan online at Medicare.gov.
Who should apply online and who is enrolled automatically
| Your situation | What to do |
|---|---|
| Already getting Social Security or Railroad Retirement benefits at least 4 months before 65 | You’re enrolled in Part A and Part B automatically. Your card arrives in the mail about 3 months before your 65th birthday |
| Turning 65 and not yet getting Social Security | Apply online at SSA.gov during your Initial Enrollment Period |
| Working past 65 with employer coverage, want only Part A | Apply online and choose Part A only, then sign up for Part B later with a Special Enrollment Period |
| Already have Part A, need Part B because employer coverage is ending | Submit forms CMS-40B and CMS-L564 online through SSA’s upload portal |
| Worked for a railroad | Contact the Railroad Retirement Board instead of Social Security |
| Under 65 with a disability | You’re usually enrolled automatically after 24 months of disability benefits. See Medicare for people with disabilities |
When to apply: your Initial Enrollment Period
Your Initial Enrollment Period lasts 7 months: the 3 months before the month you turn 65, your birthday month, and the 3 months after. According to Medicare.gov:
- If you sign up in the 3 months before your birthday month, coverage starts the first day of your birthday month.
- If you sign up in your birthday month or the 3 months after, coverage starts the first day of the month after you sign up.
Signing up early avoids gaps. Missing your window can mean waiting for the General Enrollment Period and paying a lifelong Part B late enrollment penalty. A month-by-month plan is in our turning 65 Medicare checklist.
How to enroll in Medicare online, step by step
- Check the SSA checklist. Social Security publishes a checklist for online applications. Have your Social Security number, date and place of birth, current health insurance details (including employer group coverage and its start dates) and, if you want direct deposit, your bank account information.
- Go to SSA.gov. Visit ssa.gov/benefits/medicare and start the application. You may be asked to sign in or create a my Social Security account.
- Choose what you’re applying for. You can apply for Medicare only, which lets you delay retirement benefits, or for retirement benefits and Medicare together.
- Answer the questions. You’ll confirm your identity, your work history and whether you or your spouse have employer health coverage. Answer carefully: this decides whether you can delay Part B without a penalty.
- Decide about Part B. Most people take Part B at 65. If you or your spouse are still working for an employer with 20 or more employees and have group coverage, you may be able to delay it. Read working past 65 first.
- Review and submit. Select “Submit Now.” You’ll get a receipt and an application number. Print or save it.
- Track your application. Check its status in my Social Security. Social Security may contact you if it needs documents.
- Watch for your card. Once approved, your red, white and blue Medicare card arrives by mail. You can also find your number online: see how to find your Medicare number.
Signing up for Part B online when you already have Part A
If you delayed Part B because you had employer coverage, you can use a Special Enrollment Period while you’re still covered or within 8 months after the coverage or employment ends, whichever comes first. Social Security lets you submit the Part B application (CMS-40B) and the employer form (CMS-L564) online through its upload portal, or by fax or mail. You’ll need proof of your group coverage, such as the completed CMS-L564, W-2s or pay stubs (SSA). More detail: how to sign up for Part B.
If you don’t qualify for a Special Enrollment Period, the General Enrollment Period runs January 1 to March 31, with coverage starting the month after you sign up.
After you have Part A and Part B: choosing more coverage online
Original Medicare doesn’t cover most prescriptions and has no out-of-pocket limit, so most people add coverage. Your main choices are:
- A Medicare Advantage plan, often with drug coverage built in
- A stand-alone Part D drug plan, usually paired with a Medicare Supplement (Medigap) policy
You can compare and join Medicare Advantage and Part D plans online in Medicare Plan Finder. If you don’t join a drug plan when you’re first eligible and have no other creditable drug coverage, you may owe a Part D late enrollment penalty. Already enrolled? Each fall you can review and change plans during Medicare Open Enrollment.
Common problems and how to fix them
- Can’t verify your identity online: call Social Security at 1-800-772-1213 (TTY 1-800-325-0778) or visit a local office.
- Application asks for documents: Social Security will tell you what it needs. Original documents or certified copies are usually required.
- You’re helping a parent apply: the online application asks whether you’re applying for yourself or for someone else, so a family member can complete it on the applicant’s behalf with their information.
- Your card hasn’t arrived: check your application status in my Social Security, or call Social Security.
Frequently asked questions
Can I sign up for Medicare online?
Yes. You can apply for Part A and Part B online at SSA.gov if you’re within three months of turning 65 or older and not already enrolled.
How long does the online Medicare application take?
Social Security says it normally takes 10 to 30 minutes.
How do I check my Medicare application status?
Sign in to your my Social Security account at ssa.gov/myaccount, or call 1-800-772-1213.
Do I need to sign up for Medicare if I’m already getting Social Security?
Usually not. If you’ve been getting Social Security or Railroad Retirement benefits for at least 4 months before you turn 65, you’re enrolled in Part A and Part B automatically.
Can I enroll in Medicare Advantage online?
Yes, once you have Part A and Part B. Use Medicare Plan Finder at Medicare.gov, the plan’s website, or call 1-800-MEDICARE.
Is it free to apply for Medicare online?
Yes. Applying through SSA.gov is free. Be cautious of websites or callers that ask for payment or your Medicare number to “sign you up.”
This article is general information, not individual insurance advice. Medicare365 is not affiliated with or endorsed by the U.S. government, Social Security or the federal Medicare program.