Your account number is the second set of digits on the bottom left of your check
The bottom of a check shows three separate groups of numbers, read left to right. The first group is your routing number (nine digits). The second group is your account number (typically 10 to 12 digits, though this varies by bank). The third group is the check number (usually 4 to 5 digits on the right side).
Your account number identifies your specific deposit account at your bank. It is not secret information — it appears on every check you write and on statements you may share with employers or creditors. However, you should not share it with people you do not trust, because someone with both your routing number and account number can attempt unauthorized transfers or withdrawals.
The account number is printed in magnetic ink at the bottom of the check so that sorting machines can read it automatically when checks are processed. You can also find your account number on your bank statement, in your online banking portal, or by calling your bank's customer service line.
Key Takeaways
- Your account number is the middle set of digits printed at the bottom of your check, between the routing number and the check number.
- Account numbers are typically 10 to 12 digits long, but the exact length depends on your bank.
- Your account number appears on every check you write and on your monthly bank statement.
- You can find your account number online through your bank's website, on paper statements, or by calling your bank directly.
How to locate your account number on a physical check
Hold the check so you are looking at the bottom edge. You will see three groups of numbers printed in a special magnetic ink that looks slightly raised or darker than regular printing. Starting from the left: the first group (nine digits) is the routing number, the second group (usually 10 to 12 digits) is the account number, and the third group (usually 4 to 5 digits) is the check number.
The account number sits directly after the routing number with no space between the two groups. If you are unsure which is which, remember that routing numbers are always exactly nine digits, so once you count nine digits from the left, the next digits belong to your account number.
Some checks also print your account number in the upper right corner in regular ink, alongside the check number. This makes it easier to read without a magnifying glass, though the official machine-readable version is always at the bottom.
Finding your account number without a check
If you do not have a check in front of you, your bank statement shows your account number at the top or in a summary section. Log into your online banking account and look for account information or account details — most banks display the full account number there, sometimes with the last four digits highlighted for security.
You can also call your bank's customer service number (usually on the back of your debit card) and ask for your account number. Have your Social Security number or other identifying information ready. The representative will confirm your identity and read your account number to you over the phone.
Why banks print account numbers on checks
Banks print account numbers in magnetic ink at the bottom of checks because it allows sorting machines to process thousands of checks per hour without human intervention. When you deposit a check, the bank's equipment reads the routing number and account number automatically and routes the payment to the correct account.
This system has been in place since the 1950s and remains the standard for check processing today, even though digital payment methods have become more common. The magnetic ink encoding is standardized across all U.S. banks, so any bank's equipment can read any other bank's checks.
Protecting your account number
Your account number is not classified as secret information the way a PIN or password is. It appears on every check you write, so anyone who receives a check from you will see it. However, you should still be cautious about sharing it with unfamiliar people or organizations.
Someone who has both your routing number and account number can attempt to set up unauthorized electronic transfers or recurring payments from your account. If you are paying a bill by check, the account number is necessary and expected. If someone is asking for your account number over the phone and you did not initiate the contact, verify their identity through your bank's official customer service line before providing it.
If you believe your account number has been compromised, contact your bank immediately. They can monitor your account for suspicious activity and, if necessary, close the account and issue you a new one with a different account number.
Account numbers and refund tracking
When you set up direct deposit for a tax refund, stimulus payment, or insurance refund, you will need to provide your routing number and account number. The government or insurance company uses these numbers to deposit the funds directly into your bank account rather than mailing a check.
Direct deposit is faster than waiting for a mailed check — refunds typically arrive within one to three business days after the deposit is initiated, depending on your bank. Make sure you copy your account number correctly when entering it online, because a single wrong digit will cause the deposit to fail or go to the wrong account.
Frequently Asked Questions
Is my account number the same as my routing number?
No. Your routing number identifies your bank (nine digits), while your account number identifies your specific account at that bank (usually 10 to 12 digits). Both appear at the bottom of your check, with the routing number first.
Can someone steal money if they only have my account number?
They would need both your routing number and account number to attempt a transfer. Having only the account number is not enough. However, since both numbers appear on every check you write, treat them as semi-public information and avoid sharing them with people you do not trust.
What if I enter my account number wrong when setting up direct deposit?
The deposit will either fail and be returned to the sender, or it may go to a different account at your bank if the wrong account number happens to exist. Contact your bank immediately if you realize you made an error. The sender can resubmit the deposit with the correct account number.
Do all banks use the same account number length?
No. Most banks use 10 to 12 digits, but some use fewer or more. The length varies by bank and by account type. Your specific bank's account numbers will always be the same length for all your accounts at that bank.
Can I change my account number?
You cannot change the account number on an existing account. If you need a different account number, you would need to close the current account and open a new one, which your bank can help you do. This is rarely necessary unless you suspect fraud.