Your bank's ACH number is a nine-digit code that identifies your financial institution within the automated clearing house system
The ACH number (also called the routing number or ABA number) is how the Federal Reserve and other banks know which institution holds your account. When you send money electronically—whether a paycheck deposit, bill payment, or transfer between accounts—the ACH number tells the system where that money needs to go. Without it, the transfer cannot be routed correctly.
This is different from your account number, which identifies your specific account at that bank. The ACH number identifies the bank itself. One bank might have multiple ACH numbers if it operates different divisions or acquired other banks, but most people deal with just one per institution.
Key Takeaways
- Your bank's ACH number is a nine-digit code that appears on the bottom left of your checks and identifies your specific bank branch or institution.
- You need the ACH number when setting up direct deposit, making bill payments, or transferring money between banks electronically.
- The ACH number is public information—you can find it on your checks, your bank's website, or by calling customer service.
- ACH transfers typically take one to three business days to complete, depending on when you initiate the transfer and your bank's processing schedule.
Where to find your bank's ACH number
The easiest place to locate your ACH number is on a blank check from your account. Look at the bottom left corner—you will see three groups of numbers. The first group (usually nine digits) is your ACH number. The second group is your account number, and the third is the check number.
If you do not have checks, log into your bank's website or mobile app and look for account details or routing information. Most banks display this information in the account settings or FAQ section. You can also call your bank's customer service line and ask for your routing number—they will provide it immediately. Some banks list it on statements as well.
When you need to provide your ACH number
You will need your ACH number whenever you set up a new electronic transfer into or out of your account. Common situations include setting up direct deposit for your paycheck, arranging automatic bill payments, transferring money to another bank, or receiving refunds (tax refunds, insurance refunds, or business refunds often require your ACH number for direct deposit).
If you are waiting for a refund and the issuer asks for your banking information, they are asking for your ACH number and account number so they can deposit the money directly into your account instead of mailing a check. This is faster and more reliable than waiting for mail delivery.
ACH number versus account number versus wire routing number
These three numbers serve different purposes and are not interchangeable. Your ACH number (routing number) is used for electronic transfers through the automated clearing house system—the network that handles most everyday transfers. Your account number identifies your specific account at that bank and is always needed alongside the ACH number. Your wire routing number is used for wire transfers, which are faster but more expensive, and may be different from your ACH number even at the same bank.
When someone asks for your "routing number," they almost always mean your ACH number. Wire routing numbers are less common in everyday banking and are usually only requested for international transfers or large same-day transfers.
How ACH transfers work with your number
When you provide your ACH number and account number to set up a transfer, the sending bank submits the request to the Federal Reserve's ACH network. The network uses your ACH number to route the transaction to your bank, then your account number to deposit it into the correct account. The entire process is automated and typically takes one to three business days.
The timing depends on when you initiate the transfer and your bank's processing schedule. A transfer initiated on a Friday afternoon may not begin processing until Monday morning. Weekends and federal holidays add extra days. Some banks offer faster ACH processing, but standard ACH transfers follow the one- to three-day window.
Security and privacy of your ACH number
Your ACH number is public information. It appears on every check you write and is not considered sensitive data like your Social Security number or password. You can safely share it with employers, government agencies, and legitimate businesses that need to deposit money into your account.
However, you should never share your ACH number and account number together with someone you do not trust, because together they allow someone to initiate transfers out of your account. If you are concerned about unauthorized transfers, contact your bank immediately. Most banks offer fraud protection and can reverse unauthorized ACH transfers within a set window.
What to do if your bank changes or closes
If your bank merges with another institution or closes, your ACH number may change. Your bank will notify you of this change and provide a new number. If you have automatic transfers or direct deposits set up, you will need to update them with the new ACH number to avoid failed transfers.
If you are waiting for a refund and your bank closes before the deposit arrives, contact the issuer (the IRS, your insurance company, or whoever is sending the refund) and provide your new bank's ACH number and account number. They can usually update the deposit information if the transfer has not yet been processed.
Frequently Asked Questions
Is my ACH number the same as my routing number?
Yes, ACH number and routing number are the same thing. Both refer to the nine-digit code that identifies your bank. Some banks use the terms interchangeably, and some prefer one over the other, but they point to the same number.
Can someone steal money from my account if they have my ACH number?
They would need both your ACH number and your account number to initiate a transfer. Having only the ACH number is not enough. If someone has both numbers, contact your bank immediately to report unauthorized activity. Most banks reverse fraudulent ACH transfers within 10 business days.
Do I need a different ACH number for each account I have?
No. Your ACH number identifies your bank, not your individual account. If you have a checking account and a savings account at the same bank, they share the same ACH number. Your account number is what distinguishes between them.
What happens if I provide the wrong ACH number for a refund deposit?
The transfer will be routed to the wrong bank. That bank will typically reject it and send it back to the issuer within a few business days. The issuer will then contact you to provide the correct information, which delays your refund by at least a week. Double-check your ACH number before submitting it.
How long does an ACH transfer take if I provide the correct number?
Standard ACH transfers take one to three business days from the time the sending bank submits the request. If you initiate a transfer on a Friday, it may not begin processing until Monday, so the actual time from your action to the deposit can be longer. Some banks offer next-day ACH for an additional fee.