Federal Reserve ACH Operating Circular
This operating circular, its appendices and the Federal Reserve time and fee schedules (collectively "Circular") govern the clearing and settlement of commercial automated clearing house (ACH) credit and debit items (including credit items subject to Article 4A) by the Federal Reserve Banks, sending banks, and receiving banks. Government ACH items are government by Appendix D to this Circular.
NACHA Resources: ACH Rules
The ACH system is governed by the ACH Rules of the National Automated Clearing House Association (NACHA) which provides for the interbank clearing of electronic entries for participating financial institutions.
Green Book 2000
ACH Payment Schedule
Electronic Funds Transfer
Electronic Transfer Account (ETA)
Electronic Federal Tax Payment System (EFTPS)
CTX (Corporate Trade Exchange)