Routing numbers are nine-digit numbers that identify the financial institution that holds your bank account. If the account number is misidentified, the wrong bank account will be credited or debited. The routing number typically consists of the first nine digits printed in the lower left corner of your check, which is followed by your account number and the check number. However, if you don't have a check, there are other ways to find the routing number for your account.
Contacting Your Bank
If you don't have a check or other account documentation, you won't want to guess at your routing number. According to the American Bankers Association, there are about 28,000 routing numbers currently in use. Routing numbers are assigned geographically, so depending on where your bank has branches, it might have more than one routing number. If so, your routing number is based on the location of the branch in which you opened your account.
To find your number, you can call the bank's customer service department, and the representative can give you the routing number. You also can check your bank's online system. Some banks list the routing numbers for their various branches on their website so you can find your routing number without even logging in.
Using the ABA Lookup
History of Routing Numbers
Routing numbers have been issued by the American Bankers Association since 1910. The ABA issues routing numbers only to federal- or state-chartered financial institutions that are permitted to have an account with the Federal Reserve Bank. When a new bank forms, it applies for a new routing number through Accuity, the official ABA registrar of routing numbers.
Accuity also publishes a list of all routing numbers that are currently in existence, plus those that have been retired in the past five years. That information is available only to subscribers. You could subscribe to find out your routing number, but there are easier and less expensive ways to find out