> The fastest possible resolution for your fact pattern would have been "money withdrawn on Friday" unless one or both of your banks decided to covertly extend

> The fastest possible resolution for your fact pattern would have been "money withdrawn on Friday" unless one or both of your banks decided to covertly extend you credit. This is because ACH pulls are an overnight batch process in the US. I don't think this is true. There is the NACHA same-day ACH initiative [0] which is opt-in and at least some institutions have already opted-in. I've experienced frequent same-day resolution of ACH transactions when using bank services from two very large US banks (one based on the west coast, one based in the east coast) and also a small employer credit union. It's true that my experience is not common and it often does take longer than a day. Many banks still do use overnight ACH. But I don't agree with the statement that overnight is "the fastest possible resolution" -- some banks have opted-in to doing faster and have already begun doing so. [0] https://www.nacha.org/content/same-day-ach https://www.nacha.org/content/same-day-ach