The routing number on a check identifies the bank, credit union or other financial institution where a check must be sent for payment. These numbers are issued under the guidance of the American Bankers Association, the organization that developed the routing number system. Routing numbers are also called ABA numbers, transit numbers or routing transit numbers. There are actually three numbers used to identify each check. The other two are the checking account number and the individual check number.
Routing, Account and Check Numbers
When you want your employer to deposit paychecks directly to your checking account or authorize a creditor to withdraw a payment, you must provide your checking account number and the routing number. Look on the lower left of a check and you'll see a long string of numerals. The first nine digits are the routing number. The next symbol marks the end of the routing number and is followed by another batch of digits. This second string of numerals is the checking account number. Next is another separator symbol. Last is a string of digits that identify the individual check. With electronic banking, you might not have a check available to furnish the routing number. Many banks post routing numbers, which can vary by state for the same bank, on their individual websites. Search for "routing number" or call the bank's customer service number.