What Is an ABA Number & How Do You Use It?

You may have noticed the nine-digit code at the bottom left of most checks. Called the ABA routing number (also known as a bank routing number), it identifies which financial institution is responsible for paying the check. You might also think of it as your bank’s numerical address or ID number.

It’s no big deal if you don’t know your bank’s ABA number by heart, but nevertheless, those nine digits are an important facet of many daily financial transactions, such as online bill-pay and signing up for direct deposit.

Here, you’ll learn what this number is, how it’s used, how to find it, and more information to keep your financial life running smoothly.

What Is an ABA Number?

Developed by the American Bankers Association (that’s where the ABA comes from), the main purpose of an ABA routing number is to make sure money gets where it needs to go.

In other words, routing numbers help identify which bank is responsible for paying money or giving credit to another bank. The routing number can also be used to identify which bank will receive payment or credit for a check or electronic transaction.

Rather than reading the name of a bank off a check (and potentially making a mistake), these numbers help enable bank employees and the machines that process checks do that job quickly and accurately.

Both the receiving and paying banks can use the routing number to improve the efficiency of their payment process operations.

ABA numbers also give consumers and businesses a reason to trust the banking system. Sellers can feel confident they will in fact get paid with funds from a legitimate bank and the buyers can rest easy knowing that they can prove their money is accessible and they can make a purchase or pay a bill.

What Do ABA Digits Stand for?

Here’s a closer look at what those routing number digits actually stand for (which you can also see in the image below):

The first four digits at the left indicate the Federal Reserve Bank that oversees the financial institutions in a particular location.

The next four digits identify your financial institution, or its ABA identification number.

The last digit is what’s known as a check digit number. It verifies the authenticity of the routing number.

ABA Number vs. Bank Account Number

Two crucial pieces of banking information are an account’s ABA number and the account number.

•  The ABA number identifies the financial institution where the account is held.

•  The bank account number reflects a particular, specific bank account, whether it’s checking, savings, or another kind of account.

What Is an ABA Number Used for?

The ABA number, as mentioned above, reflects the bank where an account is held. This is a critical piece of information when financial transactions take place. It allows these to be processed correctly and swiftly.

The History of the ABA Number

These routing numbers were first developed in 1910 by the American Bankers Association (ABA). At that time, it was just helpful in check processing, but it has continued to keep pace with banking innovation, including automated clearinghouses as ACH vs. checks become more popular, online banking protocols, and electronic funds transfer. It continues to play a vital role in so many basic banking matters.

Who Can Use ABA Numbers?

For a bank to be issued an ABA number, they must be a federal or state chartered financial institution and they must be eligible to have an account at a Federal Reserve Bank.

To obtain a routing number, the financial institution will work with Accuity, which is the official registrar of ABA Routing Numbers. Any newly formed financial institutions will have to submit an application to Accuity if they want to be assigned an ABA routing number.

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Where Is the ABA Number on a Check?

When looking for the ABA routing number, look at the row of numbers at the bottom of a check.

There are a lot of numbers there, but the ABA number is the nine-digit, leftmost number. It will be the first set of nine numbers that you’ll see and begins with a 0, 1, 2, or 3.

Typically, to the right of that is the consumer’s account number, then, to the right of the account number, is the number of the check.

It’s important not to get these numbers confused, since it could lead to a delay or an error in the processing of a check, as well as any online payments you authorize.

How to Find Your ABA Numbers Without a Check

Every check in a consumer’s checkbook should include their ABA number, but if a check isn’t available, there are other ways for consumers to find out the routing number they’ll need to transfer money.

Bank Statements

Recent bank statements should list the bank’s ABA routing number alongside account information. Some bank statements come by mail or as paperless electronic statements.

Bank Website

A lot of banks prominently feature their ABA numbers on their website since so many customers want to know this information. You may want to keep in mind that some larger, national banks may have different routing numbers for different states, as well as different routing numbers for wire transfers or ACH (Automated Clearing House).

Asking Your Local Bank

Customers can always call their bank to ask what the correct ABA routing number to use is. Or if you have your account at a traditional vs. online bank, you could stop by a local branch.

ABA Online Lookup Tool

The ABA actually offers a free ABA Routing Number Lookup tool that can make it simple to find routing numbers for banks. Please note that users can only utilize this tool to look up two ABA numbers per day, and can’t look up more than ten numbers in the course of a month. Also keep in mind that some banks have different numbers for different states, as well as for different transactions.

When to Use an ABA Number

While you probably won’t need to use your ABA routing number every single day, you will likely need to enter this number for a number of common transactions, such as:

•  Direct (or ACH) deposits. When someone starts a new job and wants to set up direct deposits via ACH, they will most likely have to provide their ABA number and their bank account number.

•  Wire transfers. This involves sending or receiving money via a wire transfer, which is especially common for international transactions.

•  IRS direct deposits. To receive a tax refund, the IRS gives an option to have that money refunded via direct deposit. Allowing a direct deposit can speed up the refund process.

•  Paying bills or friends. You will likely need your routing number to sign up to pay bills online or to use mobile payment apps.

•  Making a deposit to your retirement account or transferring money to another bank. When you invest money for retirement or move money between banks, you might need to set up the transactions via ACH transfer, and that requires your bank routing number.

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What’s the Difference Between ABA and ACH Numbers?

The terms ABA and ACH (Automated Clearing House) are easy to mix up. ABA numbers are sometimes referred to as ACH numbers, although this is not technically correct.

ACH refers to an electronic fund transfer made between banks that is processed through the Automated Clearing House network.

The ACH is the main system that financial institutions utilize for electronic fund transfers. When using ACH, the funds are electronically deposited in the designated financial institutions, allowing payments to be made online.
Unlike wire transfers, ACH transfers are typically used for relatively small, and often regular, payments.

Consumers can utilize ACH for many types of transactions that put money in someone’s account and often do so without realizing it.

For example, through ACH someone could have their paychecks directly deposited into their checking and savings account or can make monthly debits for any routine bill payments, such as a student loan payment.

Many merchants allow their customers to pay their bills via ACH. The payer typically has to provide an account number and bank routing number to do so.

Online services transactions can also be conducted with ACH and most banks and credit unions use ACH for online bill payment services.

The Takeaway

The ABA routing number is a sequence of nine digits used by banks to identify specific financial institutions within the U.S. Found on the lower left of a check (as well as online and on your bank statements), you need to know your routing number for many basic financial transactions, such as paying bills online, signing up for direct deposits at work, using a mobile payment app, as well as transferring money from one financial institution to another.

Interested in opening an online bank account? When you sign up for a SoFi Checking and Savings account with direct deposit, you’ll get a competitive annual percentage yield (APY), pay zero account fees, and enjoy an array of rewards, such as access to the Allpoint Network of 55,000+ fee-free ATMs globally. Qualifying accounts can even access their paycheck up to two days early.

FAQ

Are ABA numbers and routing numbers the same thing?

Yes, an ABA number and a bank routing number are the same thing. Those nine digits at the bottom of a check and to the left can be referred to by either term.

Is an ABA number always 9 digits?

Yes, the ABA or bank routing number is always nine digits long.

Does a debit card have an ABA number?

Debit cards do not have routing numbers; those nine digits are only found on checks to identify the financial institution that issued the check. Instead, debit cards have an account number as well as a PIN.

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