The account number is the second set of digits on the bottom of your check

Your checking account number appears on the bottom left of a check, printed between two sets of numbers. The first set (on the far left) is your bank's routing number. The second set, which is your account number, comes immediately after. Both are printed in a special magnetic ink that machines can read.

The account number is typically 10 to 12 digits long, though the length varies by bank. It identifies your specific account at your bank, separate from every other account that bank holds. When someone deposits a check you write, the routing number tells their bank where to send the money, and your account number tells your bank which account to pull it from.

You will also see a four-digit number at the far right of the bottom line — that is the check number, which is different from your account number. The check number simply identifies which check in your book you are using.

Key Takeaways

  • Your account number is the middle set of digits on the bottom of your check, between the routing number on the left and the check number on the right.
  • Account numbers are typically 10 to 12 digits long and identify your specific account within your bank.
  • The numbers are printed in magnetic ink so that check-processing machines can read them automatically.
  • You can also find your account number on your bank statement, your debit card, or by logging into your online banking.

How the three numbers on the bottom line work together

The bottom of a check contains three separate pieces of information, each with a different job. The routing number (leftmost) directs the check to the correct bank. Your account number (middle) directs it to the correct account within that bank. The check number (rightmost) is simply a reference for your own records.

When you write a check, the person who receives it deposits it at their bank. That bank reads the routing number first and sends the check to your bank. Your bank then reads your account number and removes the money from your account. If the check bounces or there is a dispute, both banks use the routing number and account number to track down the transaction.

The magnetic ink at the bottom of the check is called MICR (Magnetic Ink Character Recognition). It allows machines to process thousands of checks per hour without human intervention. If you write on the MICR line or if the numbers become smudged or faded, the check may not process correctly.

Where else to find your account number

You do not need a check to find your account number. Your bank provides it in several places. Your monthly bank statement lists your account number at the top. If you have online banking, your account number appears when you log in — usually on the main dashboard or in an account details section. Your debit card also has your account number printed on it, though it may be abbreviated or displayed differently than on a check.

If you cannot locate your account number through any of these methods, call your bank's customer service line or visit a branch in person. They can provide it immediately. You will need your account number if you set up direct deposit, arrange automatic bill payments, or receive a wire transfer.

What your account number does not tell you

Your account number is not the same as your Social Security number, tax ID, or any other personal identifier. It is specific to that one account at that one bank. If you have multiple accounts at the same bank — a checking account and a savings account, for example — each one has its own account number.

Sharing your account number and routing number is generally safe. Merchants and employers need both numbers to deposit money into your account or set up automatic payments. However, you should not share these numbers with anyone you do not trust, because someone with both numbers could potentially set up unauthorized withdrawals from your account.

Reading a sample check

On a typical check, the bottom line reads something like this: 121000248 1234567890 1234. The first number (121000248) is the routing number. The middle number (1234567890) is your account number. The last number (1234) is the check number. The routing number identifies a specific bank or credit union. The account number identifies your account within that bank. The check number is just for your reference.

Some checks also print your account number in the upper right corner in regular (non-magnetic) ink, but this is optional and not required for the check to process. The only numbers that matter for processing are the ones in magnetic ink at the bottom.

Why banks print account numbers on checks

Banks print your account number on every check because it is the fastest way for other banks to identify where the money should go. Before electronic processing, bank employees had to read checks by hand and sort them manually. The magnetic ink made this process faster and more accurate. Today, machines do the sorting, but the system remains the same.

The account number on a check is also a security feature. If someone steals a blank check from your book, they cannot use it without knowing your account number. The number is printed in a specific format that is difficult to forge, and banks train their staff to spot altered or counterfeit checks.

What to do if you cannot read the numbers on a check

If the numbers on the bottom of a check are faded, smudged, or damaged, the check may not process correctly. Some banks will still accept it if the damage is minor, but others will reject it and return it to the person who deposited it. If you are writing a check and the numbers are hard to read, order a new book of checks from your bank.

If you are trying to read a check someone gave you and the numbers are unclear, contact the person who wrote the check and ask them to provide their account number and routing number directly. You can also contact their bank if you know which bank they use, though the bank may not provide this information without the account holder's permission.

Frequently Asked Questions

Can someone use my account number to steal money from my account?

Having only your account number is not enough to steal money. A thief would also need your routing number, and even then, most banks require additional verification before processing large transfers. However, someone with both your account and routing number could potentially set up unauthorized automatic withdrawals, so you should not share these numbers with people you do not trust.

Is my account number the same as my debit card number?

No. Your debit card number is different from your account number. The debit card number is what you use to make purchases or withdraw cash. Your account number is used for direct deposits, wire transfers, and check processing. Both are connected to the same account, but they are separate numbers.

What if I write down my account number wrong?

If you provide an incorrect account number for a direct deposit or automatic payment, the money will go to the wrong account. The sending bank will eventually catch the error and return the money, but this can take several days or weeks. Always double-check your account number before setting up any automatic transfers.

Do I need my account number to cash a check at my own bank?

No. You only need to show your ID and the check. The teller can look up your account using your ID. However, if you are depositing a check into your account, the bank will use the account number printed on the check to route the money correctly.

Why is my account number different from my check number?

Your account number identifies your account. Your check number identifies which individual check you are using. You might write 50 checks from the same account, and each one has a different check number, but they all have the same account number. The check number helps you track which checks you have written.