Payment Radar
ACH Network Growth and Operational Changes for Merchants
The article reports on the growth of the ACH network, driven by B2B payments, open banking, and Same Day ACH.
Payment RadarOriginal source: Payments Journal · linked publisher media; native reuse rights require confirmation 
What changed
The US ACH network, the Automated Clearing House, the US bank-to-bank electronic transfer network run by Nacha for payroll, direct deposit, and business payments, is expanding its capacity for large business payments. Starting September 17, 2027, the transaction cap for Same Day ACH will increase from $1 million to $10 million. This change removes the need for exception processes that were previously required to move larger sums quickly. Additionally, the industry association that governs the ACH network’s rules and same-day ACH, Nacha, is introducing new fraud monitoring rules. These rules require businesses to implement verification processes whenever payment information is changed, targeting scams like business email compromise.
Why a business should care
The cap lift directly impacts cash flow and treasury operations. Merchants and B2B payers will be able to settle larger invoices with same-day speed without manual overrides or delays. This simplifies liquidity management and reduces administrative friction. The new fraud rules address a critical vulnerability. Scammers frequently target payment details to redirect funds. By mandating verification for any changes to account information, the rules aim to stop unauthorized transfers before they happen.
Who it affects
This applies to US merchants and businesses that rely on B2B payments, Same Day ACH, or pay-by-bank checkout options. Any organization that processes or sends large electronic transfers will be impacted by the higher cap. Companies that handle payment information updates will also need to adjust their internal controls to meet the new verification standards.
What to consider doing
Update your treasury and settlement workflows to prepare for processing Same Day ACH transactions up to $10 million by September 17, 2027. Specifically, audit your current payment change verification procedures and implement a mandatory multi-step validation step for any request to update bank account details.
Uncertainty and risks
The rules are scheduled for implementation in 2027, giving businesses time to adjust. However, the exact technical requirements for the verification processes are not yet detailed. Businesses should watch for official Nacha guidance on the specific validation methods required to ensure compliance.
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