Your Medicare number is printed on the front of your red, white, and blue Medicare card, directly below your name. That is where the Medicare number appears on your card: an 11-character code labeled “Medicare Number,” made up of uppercase letters and numbers in a format like 1EG4-TE5-MK73. Its official name is the Medicare Beneficiary Identifier, or MBI, and it replaced the older Social Security–based numbers to better protect your identity.1Medicare. Your Medicare Card
What Else Is Printed on the Front
The front of the card carries four things: your name, your Medicare number, whether you’re enrolled in Part A (hospital insurance) or Part B (medical insurance) or both, and the date each part of your coverage started.1Medicare. Your Medicare Card The Medicare number sits right below your name in large print and is the most prominent identifier on the card. You’ll see dashes grouping the characters on the printed card, but those dashes are just for readability. The actual MBI is 11 characters with no dashes.
How to Read the 11 Characters
The MBI follows a fixed pattern, which matters when you’re reading it aloud on the phone or typing it into a form. Six letters that could be confused with numbers are permanently excluded: S, L, O, I, B, and Z. So a character that looks like the letter “O” is actually the number zero, and one that looks like “I” is actually the number one.2Centers for Medicare & Medicaid Services (CMS). Understanding the Medicare Beneficiary Identifier (MBI) Format
The character positions follow a set rule:
- Positions 1, 4, 7, 10, and 11 are always a number.
- Positions 2, 5, 8, and 9 are always a letter.
- Positions 3 and 6 can be either a letter or a number.
The first character is always a number between 1 and 9, so your MBI will never start with zero.3Centers for Medicare & Medicaid Services (CMS). Understanding the Medicare Beneficiary Identifier (MBI) Format Knowing the pattern helps you catch mistakes: if the second character is a numeral, something has been entered wrong. The MBI is randomly generated and contains no hidden information about your age, state, or eligibility.
If You Can’t Find Your Card
You don’t have to wait for a replacement in the mail to get your number. Log into your Medicare account at Medicare.gov and print an official copy of your card. Providers will accept the printed copy.1Medicare. Your Medicare Card If you don’t have an online account yet, you can create one on the same site.
To order a physical replacement, log in at Medicare.gov and request a new card, or call 1-800-MEDICARE (1-800-633-4227). TTY users can call 1-877-486-2048.4Social Security Administration. How Do I Get a Replacement Medicare Card? Replacement cards generally arrive within 30 days, and the printed copy works as proof of coverage in the meantime.
Keep the Number to Yourself
Once you’ve located your MBI, treat it like a credit card number. It can be used to file fraudulent claims in your name. Medicare will never call, text, email, or message you on social media to ask for your Medicare number, Social Security number, or bank information, so anyone contacting you out of the blue for those details is running a scam.5Federal Trade Commission (FTC). Avoid Scams During Medicare’s Open Enrollment Period Caller ID isn’t reliable either, since scammers can make your phone display Medicare’s real name and number.6Federal Communications Commission (FCC). Older Americans and Medicare Call Scams Share the number only with your doctors, authorized providers, and insurance agents you contacted yourself. If you think your number has been misused, call 1-800-MEDICARE.7CMS.gov. Reporting Fraud