what is transit aba number

An ABA transit number, also known as an ABA routing or routing transfer number, is a nine-digit code used to identify specific U.S. financial institutions. It appears on standard checks and is a numeric address for each bank. The ABA routing transit number is the left-most number on a check, followed by the account number, and then by the number of the check. It is used for payment transactions within the United States, including paper checks, wire transfers, and ACH transactions. Without ABA transit routing numbers, it would not be possible to deposit a check using a mobile phone. ABA transit numbers allow employers to deposit checks automatically and for those checks to clear faster than a manual check. The numbers are also used in Fedwire transfers, and each digit making up the ABA routing number plays a role in the process. Routing transit numbers were developed by the American Bankers Association in 1910 to indicate check processing endpoints. Since then, the numbers use has expanded to include participants in check clearing between banking institutions, automated clearinghouses, and online banking activities.