IIRC, ACH Deposits are also often pre-auth'd. When I worked at a Credit Union in college, we would get an ACH file that had preauth'd ACH deposits - usually fr

IIRC, ACH Deposits are also often pre-auth'd. When I worked at a Credit Union in college, we would get an ACH file that had preauth'd ACH deposits - usually from employers - and we would go ahead and credit the account that day. The actual deposit would come in the next business day.