Many people are quoting a percentage, but don't understand all the fees that can be involved.

Most US merchants who have a electronic credit machine, or process online pay 2-3% for MC/Visa. Some are also charged per authorization, say 10-30 cents each. Then there may be monthly charges like statement fees, non-swiped transactions (phone or online orders where the card isn't physically present), terminal rentals, insurance and more. This doesn't even count the extra charged for international cards, Amex, business cards, and such.

My first merchant account started over 20 years ago, and for the time was not bad for non-swiped transactions. About 4%. It went down to about 3.5% as volume increased.

Over the next 20 years, the company doing the processing was sold, and each new place was worse than the last. Since most of mine was non-swiped it only went up. When analyzing costs a couple of years ago, I was shocked to find I was paying 6%.

I contacted the company for reduction, but was ignored. I transitioned over to Paypal card processing 18 months ago. Not flawlessly, though. The first few months there were numerous times transactions wouldn't work.

It did get substantially better, and I cancelled the old account. They were shocked when I did so. Horrid customer service, even at the end.

So with the 2.4% I pay, plus a $30 a month fee, I save about half. Substantial money.