Account Number

What is a bank account number?

A bank account number is a unique string of characters that identifies a specific bank account. It appears on your bank statements and (for checking accounts) as the middle sequence of numbers printed at the bottom of paper checks. The account number, together with the bank’s routing number, directs deposits and payments to the correct account.

Key takeaways

• Account numbers identify individual accounts and work with routing numbers to route transactions.
• They usually appear on checks, bank statements, and online account pages.
• Account numbers are sensitive information; use strong security practices (multifactor authentication, password managers, account monitoring).

How account numbers work

On a paper check you’ll commonly see three sets of numbers along the bottom:
* Left — nine-digit routing number (identifies the financial institution).
* Middle — your account number (identifies your account at that institution).
* Right — the check number.

Payroll, vendors and other payees use your account and routing numbers to set up direct deposits and automated payments. Electronic transfers and ACH transactions rely on these numbers to route funds.

Account number vs. routing number

• Routing number: identifies the bank or credit union and is used to route transactions to that institution. In the U.S., it’s a nine-digit code.
• Account number: identifies your individual account at that institution. Both are required for most ACH transfers and direct deposits.

Where to find your account number

• Printed on your monthly bank statement.
• On paper checks — the middle number sequence at the bottom.
• In your bank’s online or mobile app under account details.
• By visiting a branch or contacting your bank (use secure channels and identity verification).

Note: Your account number is not the same as your debit or credit card number.

Typical length

Most account numbers are 8–12 digits, though some institutions use longer numbers (up to 17 digits in some cases). Formats vary by bank.

How to protect your account number

Account numbers can be used in fraudulent transactions if combined with other information. Protect them with these practices:
* Use multifactor authentication (MFA) on online banking.
* Use strong, unique passwords and a reputable password manager.
* Enable account alerts and review statements regularly for unauthorized activity.
* Avoid sending account numbers via insecure channels (email, unverified texts).
* Shred old checks and sensitive documents before disposal.
* Report suspicious activity to your bank immediately; request account number changes if compromise is suspected.

FAQs

Q: Can someone steal money with only my account number?
A: In some cases, fraudsters can initiate ACH or bill-pay transactions with an account number plus routing number, but banks have controls and fraud protections. Rapid detection and reporting reduce losses.

Q: Is my debit card number the same as my account number?
A: No. Debit and credit card numbers are separate and typically 16 digits; they do not replace your bank account number.

Q: How do I change my account number?
A: Contact your bank. Changing an account number often requires opening a new account or a bank-initiated number change and updating any direct deposits or automatic payments.

Bottom line

A bank account number is a core identifier used to route deposits and payments. Know where to find it (checks, statements, online), understand how it works with the routing number, and protect it with strong security practices like MFA, strong passwords, secure communication, and active account monitoring.

Sources

• American Bankers Association — routing number information
• U.S. Cybersecurity & Infrastructure Security Agency — guidance on multifactor authentication
• Bank educational resources (e.g., bank help pages on account numbers and checks)