ABA_NUMBER, also known as the bank fraction number or routing transit number , is an optional alphanumeric field used for U.S. Installations. The ABA number consists of three elements: *3 character bank transit *5 character branch transit *1 character check digit. ---- ![Notes|Edit:Internal.ABA_NUMBER] [{InsertPage page='Internal.ABA_NUMBER' default='Click to create a new notes page'}]