How a Bank Account Number Works

A bank checking account’s number is located at the bottom of the paper check. You’ll see three sets of numbers in a computer-readable font at the bottom of the check:

  • The first set of numbers on the left is the nine-digit bank routing number.
  • The middle numbers are your account number.
  • The third number is the number of the check.1

Payroll processing offices use checking account numbers to set up direct deposit payments for employees.

Protecting Bank Account Numbers

Bank account numbers are vulnerable to identity theft and fraud. This is why you have to answer questions about your mother’s maiden name when you try to make routine changes to an account like your bank account. The means of making it difficult for hackers to steal account numbers have in recent years taken the form of password managers along with multi-factor authentication, or MFA, systems.

Businesses now often employ a hard-to-hack master password to unlock an electronic vault of customers’ bank account numbers and other sensitive data. Consumers are becoming accustomed to multifactor authentication, which adds another step before granting access to a bank account, such as requiring a fingerprint, voice activation, or a time-sensitive code sent to the cellphone number on record.2

These are just some of the means of protecting users’ bank account numbers in an increasingly vulnerable online environment.

The traditional check layout applies to most personal checks, but some business checks and bank-printed checks have other formats.

Account Number vs. Routing Number

On a paper check, the nine-digit routing number identifies specific financial institutions within the U.S. The number identifies the check as having been issued by a federal- or state-chartered bank that maintains an account with the Federal Reserve.1

This system dates back to 1910 and was developed initially as a way to help bank clerks sort through piles of checks and assign them to the correct drawer.3 Today, electronic services use them in much the same way for wire transfers, to draw a payment from a deposit at the correct institution.

The individual’s bank account number works together with the routing number to identify the right account holder at the right institution.

How to Locate Your Bank Account Number

You can find your bank account number on your monthly bank statement, or by visiting a branch of your bank.

If you are using a checking account, the account number is also printed on your paper checks. You can find it printed between the bank’s routing number and the check number, as shown below.

Image by Sabrina Jiang © Investopedia 2020

How Do You Find the Account Number on a Check?

You can find your bank account number printed at the bottom of your paper check. This is the second sequence of numbers, printed between the nine-digit routing number and the shorter check number. This number can also be found on your account statement.1

How Long Is a Bank Account Number?

A bank account number is usually eight to 12 digits long, but some account numbers have up to 17 digits. Note that this is not the same as your debit card number or credit card number.4

How Do You Find Out Your Account Number?

You can find your bank account number on your bank statements, printed at the bottom of a paper check, or by logging on to the bank’s website. If you can’t find it in these ways, try visiting a bank branch in person.

The Bottom Line

A bank account number is a unique identifier for each account at a bank or other financial institution that you have. Along with the routing number, the bank uses this number to make payments and accept deposits. Due to the increase in identity theft and fraud, it is important to actively protect your bank account number and other banking information.