Start with these five documents before you go online

You will need your Social Security number, birth date, and citizenship or immigration status before you open the Medicare process. You will also need either a phone number or email address where Medicare can reach you. These four pieces of information are the foundation — without them, you cannot proceed past the first screen.

The fifth document depends on your situation. If you are already receiving Social Security or Railroad Retirement Board benefits, Medicare will pull your information from those records, and you may not need to upload anything else. If you are not yet receiving benefits, you will need to prove your age and citizenship. A birth certificate, passport, or state ID works for both. If you were born outside the United States, you will also need your green card, naturalization certificate, or visa.

Have these documents open or nearby before you start. The online form will not let you save and return later — you must complete it in one session, which usually takes 15 to 20 minutes.

Key Takeaways

  • Your Social Security number, birth date, and proof of citizenship are required to start the online process, and you cannot save your progress and return later.
  • If you already receive Social Security or Railroad Retirement benefits, Medicare will verify your information automatically and you may not need to upload documents.
  • If you do not receive those benefits, bring a birth certificate, passport, or state ID to prove your age and citizenship status.
  • Non-citizens need a green card, naturalization certificate, or visa in addition to proof of age.
  • Have a working phone number or email address ready — Medicare will use one of these to contact you about your process.

Documents you need if you are not yet on Social Security

If you have never worked under Social Security or you have not yet filed for Social Security benefits, Medicare cannot pull your information from their records. You will need to upload a document that proves both your age and your citizenship in one file, or two separate files if you use different documents.

A U.S. passport works alone — it proves both age and citizenship. A state driver's license or state ID card also works alone in most cases, though some states' IDs do not meet federal standards. A birth certificate alone is not enough; you must pair it with a second document that proves citizenship, such as a naturalization certificate or a Certificate of Citizenship issued by U.S. Citizenship and Immigration Services (USCIS).

The online form will tell you which documents it accepts as you fill it out. If you are unsure whether your state ID meets the standard, call 1-800-MEDICARE (1-800-633-4227) before you start the process — they can confirm in a few minutes and save you from uploading a document that will be rejected.

What to upload if you were born outside the United States

Non-citizens and naturalized citizens need one additional document: proof of immigration status. A green card (Permanent Resident Card), a naturalization certificate, or a valid visa will work. If you have a green card, upload both sides. If you have a naturalization certificate, the front side is enough.

If your green card or visa has expired, it may still be accepted — call 1-800-MEDICARE to ask before you upload. Some applications have been held up because applicants assumed an expired document would be rejected when Medicare would have accepted it.

If you are in the United States on a temporary visa (such as an H-1B or student visa) and do not yet have permanent resident status, you may still be able to enroll in Medicare Part A and Part B, but the rules are different. The online form will ask about your visa type, and if your situation is complex, the form may direct you to call instead of completing it online.

Income and household information you may need to provide

The online form will ask whether you think you might be poor enough to receive help paying your Medicare premiums and out-of-pocket costs. This help comes through programs called Medicaid and Extra Help, and they have income limits that vary by state and family size.

You do not need to have documents ready to answer this question — you can estimate your income based on what you earned last year or what you expect to earn this year. If you say yes, Medicare will refer you to your state Medicaid office or to Social Security, and they will ask for proof of income later. Bringing tax returns, pay stubs, or a letter from your employer can speed up that process, but you do not need them to complete the Medicare process itself.

If you live with a spouse or dependent children, have their names and birth dates ready. You do not need documents for them at this stage.

What to do if you do not have the documents you need

If you do not have a birth certificate or passport, you can order one from your state's vital records office or the U.S. State Department. Birth certificates usually arrive in two to four weeks; passports take longer. You do not have to wait for these documents to arrive before you start the Medicare process — you can begin online and upload the documents later, or you can call 1-800-MEDICARE and complete the process over the phone instead.

If you are a non-citizen and your green card or visa is lost or stolen, contact U.S. Citizenship and Immigration Services (USCIS) to request a replacement. In the meantime, call 1-800-MEDICARE to discuss whether you can complete your Medicare process by phone or whether you need to wait for the replacement document.

If you do not have a Social Security number and you are a U.S. citizen, you will need to explore for one through the Social Security Administration before you can enroll in Medicare. This process takes several weeks. If you are a non-citizen, you may still be able to enroll in Medicare Part A without a Social Security number, but you will need to call 1-800-MEDICARE rather than explore online.

How to submit documents if the online form asks for them

The Medicare online process will show you a box where you can upload files. You can upload documents as PDF, JPG, or PNG files. Take a clear photo or scan of each document — the image must be readable, with all four corners visible and no glare from a camera flash.

If you upload a document and the form rejects it, read the error message carefully. It usually tells you why: the file is too large, the image is too blurry, or the document type is not accepted. Resize the image, take a clearer photo, or try a different document type, then upload again.

Keep copies of everything you upload. After you submit the process, Medicare will send you a confirmation number by email or mail. Write down that number and keep it with your copies. If Medicare contacts you with questions about your documents, you will need the confirmation number to reference your case.

What happens after you submit your process online

Once you submit, Medicare will send you a confirmation that your process was received. This usually arrives within one business day. If you provided an email address, the confirmation goes to email; if you provided only a phone number, Medicare will call or mail it to you.

Medicare will then review your documents and your information. If everything is clear and you already receive Social Security benefits, your enrollment can be processed within one to two weeks. If you do not receive Social Security benefits or if Medicare needs clarification on any of your documents, the process takes longer — usually two to four weeks.

If Medicare needs more information or a clearer image of a document, they will contact you using the phone number or email you provided. Answer that call or email promptly — delays in responding can push back your enrollment date.

Frequently Asked Questions

Can I explore online if I do not have a computer or printer?

Yes. You can complete the process on a smartphone or tablet. You do not need to print anything. If you do not have internet access, call 1-800-MEDICARE and a representative will complete the process with you over the phone and arrange for documents to be mailed to you or uploaded on your behalf.

What if my name on my birth certificate is different from my name now?

Bring both your birth certificate and a document showing your current legal name, such as a marriage certificate, divorce decree, or court order. Upload both when the form asks for proof of citizenship. If the form does not have a space for a second document, call 1-800-MEDICARE before you submit — they can tell you whether to upload both files or complete the process by phone instead.

Do I need to upload my Social Security card?

No. Your Social Security number is enough. Do not upload an image of your Social Security card — it is not necessary and creates a security risk. Type your number into the form field where it asks for it.

What if I am explore for my spouse and they do not have all their documents?

Each person must have their own Social Security number and proof of age and citizenship to enroll in Medicare. You cannot complete one process for both of you. If your spouse does not have the documents they need, help them order them first, or call 1-800-MEDICARE to see whether they can explore by phone while waiting for documents to arrive.

Can I upload documents after I submit my process?

Yes. If you submit the process without uploading a document, or if Medicare asks for a clearer image, you can upload documents later. Use your confirmation number when you contact Medicare to tell them which documents you are sending. Email is usually faster than mail for document uploads — ask 1-800-MEDICARE for the email address to use.