Philosopher - 2:06 pm on Jun 17, 2011 (gmt 0)
It generally depends on his banking institution. Most voids I do are immediate. I've tested on my own cards in the past and with my bank once I void it...it's gone.
I've had a couple of customers who I voided and it took a day to drop off. It's not supposed to work that way, but apparently their bank is slower to take them off.