US ACH Processing Docs

ACH payment lifecycle, NACHA-based settlement concepts, and system architecture for enterprise payment processing.

End-to-end ACH credit processing flow from origination through Fed settlement to receiver posting.

Hold periods, availability windows, Reg CC compliance, and the business rules governing when funds become available.

Return codes R01–R29, NOC handling, dishonored returns, and the full return lifecycle with deadline rules.

Posting logic, ledger updates, general ledger reconciliation, and batch settlement integration patterns.

NACHA SEC codes (PPD, CCD, WEB, TEL), transaction type codes, and addenda record conventions.

End-to-end scenario walkthroughs for common ACH payment use cases including payroll, vendor payments, and consumer billing.

Duplicate detection, velocity limits, OFAC screening, same-day ACH constraints, and enterprise-grade safeguards.