What is the maximum processing time for a Same Day ACH transaction?

The correct answer is end of the same business day.

Same Day ACH transactions are designed to provide a quicker processing timeline to meet various financial needs. The crucial aspect of Same Day ACH is that it allows transactions to be processed on the same business day as they are submitted. This service is especially beneficial for urgent payments, such as payroll or time-sensitive invoices, as it enables the receiving party to access funds more quickly compared to standard ACH, which can take one to two business days.

While it's important to note that Same Day ACH transactions must be submitted to the receiving financial institution within specific cut-off times to be processed within that same business day, the fundamental principle remains that the processing happens by the end of the same business day rather than extending to 24 hours or beyond. Consequently, this service provides both efficiency and agility in the realm of electronic payments.