Why do electronic fund transfers take so long?
They don’t take that long to complete, no, but your comparison about an instantly clearing check isn’t accurate either: that check isn’t cleared instantly, your bank is just giving you some benefit of the doubt and opening up the money immediately. As others have mentioned, the ‘float’ is a notable revenue generator for the bank. They have any number of strategies for paying themselves with things like that. The ‘instant clear’ they give you for those deposited checks (which I suspect if you check your agreements are limited to under 250-500 amounts and ‘in-state’ checks, depending on your location and if it’s a bank or CU) are an easy sop to throw people that distract from some of the other more egregious things they do, as well as fend off efforts by local PIRGs to mandate the limits (as happened in Florida in the late 80s).
