Quick and dirty math here: Stripe charges $275 per month for card revenues up to $21,000 per month. I took a look at http://truecostofcredit.com (courtesy of FeeFighters) and the merchant fees per transaction vary widely based on the type of merchant as well as card type. For the sake of argument, let's say the average Visa/MC transactions costs the merchant 1.75%. And let's say that the average AmEx transaction costs the merchant 3.5%. Now let's assume it's an 80%/20% distribution between MC/Visa and AmEx transactions, respectively, bringing a blended rate of 2.1%. Assuming that the merchant is charged 2.1% per transaction by their credit card company, the tipping point is $13,095 of revenue per month. Anything above and beyond that and this is a good deal. Below it, it's not (aside from the fact that's a fixed cost versus a variable one which is worth something).