Bank account numbers in the United States contain only numbers, no letters

A legitimate U.S. bank account number is made up entirely of digits—0 through 9. If you see letters mixed into what someone claims is your account number, it is not your actual account number. Banks do not use letters in account numbers for domestic accounts.

This matters because scammers sometimes send fake account numbers that include letters to confuse you or to make you think you are looking at something official. A real account number from your bank will always be numeric only. If you are unsure whether a number you received is legitimate, call your bank directly using the phone number on your debit card or statement—never use a number from an email or text message.

Key Takeaways

  • U.S. bank account numbers contain only digits, never letters or special characters.
  • Account numbers typically range from 8 to 17 digits depending on the bank, but the format is always numeric.
  • If someone gives you an account number with letters in it, verify it directly with your bank before using it.
  • International bank accounts may use letters (like IBAN codes in Europe), but domestic U.S. accounts do not.
  • Scammers sometimes include letters in fake account numbers to make fraudulent instructions look more official.

How long U.S. account numbers actually are

Account numbers vary in length by bank, but they stay within a predictable range. Most U.S. banks issue account numbers between 8 and 17 digits long. The exact length depends on the bank's internal system—there is no federal standard that sets one length for all banks.

Your bank statement, online banking portal, and debit card all display your account number in the same format: digits only. If you see your account number written out anywhere official (a statement, a receipt, a bank website), count the characters. You will find only numbers.

Why letters do not appear in domestic account numbers

Bank account numbers are designed to work with automated systems that process payments, transfers, and deposits. These systems read numbers, not letters. Adding letters would break the routing and sorting logic that moves money between accounts and between banks.

The routing number (a separate 9-digit code that identifies your specific bank branch) is also numeric only. Together, your routing number and account number form the complete address for your money. Both must be numbers for the system to work.

International account numbers do use letters

If you are sending or receiving money from outside the United States, you may encounter account numbers that include letters. An IBAN (International Bank Account Number) used in Europe, the Middle East, and parts of Africa includes both letters and numbers. An IBAN can be 15 to 34 characters long and always starts with a two-letter country code.

A SWIFT code (also called a BIC code) used for international wire transfers is also alphanumeric—it contains both letters and numbers. But these are not your U.S. bank account number. They are additional codes used only for international transfers. Your actual account number at a U.S. bank remains numeric.

What to do if you receive an account number with letters

If someone—whether a company, a government agency, or a person—gives you an account number that contains letters, stop and verify before using it. Call the organization directly using a phone number you find yourself (not one provided in the same message). Ask them to confirm the account number over the phone.

This is especially important if you are being asked to send money, set up a transfer, or provide payment information. Scammers often send emails or texts that look like they come from banks, the IRS, or other trusted sources, and they include fake account numbers with letters to make the message seem more official or to confuse you into thinking it is legitimate.

How to spot a fake account number in a message

A message asking you to send money and including an account number with letters is almost certainly a scam. Real banks, the IRS, and government agencies do not ask you to transfer money to account numbers in unsolicited emails or texts. They also do not send account numbers that break the numeric-only rule.

If you receive such a message, do not respond to it or click any links. Instead, contact the organization directly using contact information you find on their official website or on a statement you already have. Report the message to the organization and to the Federal Trade Commission at reportfraud.ftc.gov.

Frequently Asked Questions

Can a bank account number have dashes or spaces in it?

The actual account number contains only digits. Banks and documents may display it with dashes or spaces for readability (like 123-456-7890), but those are formatting only. When you enter your account number into a system, you typically type only the digits without the dashes or spaces.

What if my bank statement shows letters next to my account number?

Letters next to your account number on a statement usually indicate the account type (like "C" for checking or "S" for savings), not part of the account number itself. The account number itself is still numeric only. Check your bank's legend or key at the bottom of the statement to see what the letters mean.

Do credit card numbers have letters in them?

No. Credit card numbers, like bank account numbers, are numeric only. A credit card number is typically 13 to 19 digits long. If someone gives you a credit card number with letters, it is not a real credit card number.

What is a reference number, and is it different from an account number?

A reference number is a separate code used to track a specific transaction or interaction. It may contain letters and numbers. It is not your account number. Banks often provide reference numbers in confirmation emails or receipts so you can look up a transaction later, but your actual account number remains numeric only.