the fixed acquirer network fee (fanf) is a fee that visa began assessing each of its merchants for in april 2012. ranging from us$1.25 to $380,000, it is based on the size of the merchant. for example, a high-volume merchant category code (mcc) with over 4000 locations would have to pay a price near the top of the spectrum, while a small business would end up paying somewhere near the bottom.