What Is an Account Number And Where Do You Find It?

What Is an Account Number?

An account number is a unique string of numbers and, sometimes, letters and other characters that identify the owner of an account and grant access to it. In the U.S., the Social Security number was the primary identifier until its vulnerability to identity theft forced the practice to be abandoned. In today's electronic age, the most important account number for many people is the checking account number.

Key Takeaways

  • An account number is a unique identifier of the owner of a service and permits access to it.
  • Account numbers are attached to virtually every transaction anyone makes.
  • In the current electronic era, account numbers are vulnerable to fraud.
  • Multi-factor identification and other security measures protect identification numbers as well as passwords.
  • You can find your account number on the bottom of a paper check, just after the routing number.

How an Account Number Works

The checking account 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 number on the left is the nine-digit bank routing number.
  • The middle number is your account number.
  • The third number is the number of the check.

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

In addition to checks, account numbers are attached to just about any transaction a consumer or business can make. Sales receipts, subscription services, credit card accounts, and store club memberships all have them.

Protecting Account Numbers

Identification numbers, in addition to passwords, are vulnerable to identity theft and fraud. This is why we have to answer annoying questions about our mothers' maiden names when we try to make routine changes to an account. The means of making it difficult for hackers to steal account numbers currently are taking the form of password managers along with multi-factor authentication systems.

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

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

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

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.

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. 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 account number works together with the routing number to identify the right account holder at the right institution.

How to Locate Your Account Number

You can find your 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.

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.

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 on the bank's website. If you cannot find either type of document, try visiting a branch in person.

The Bottom Line

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

Article Sources
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  1. Chase. "What Is a Bank Account Number?"