Starting today (1 September 2017), every business across Australia will be banned from imposing "excessive surcharges" on customers who choose to pay merchants via certain credit, debit or prepaid cards. Specifically, the new ban restricts the amount a business can charge its customers for using EFTPOS (debit and prepaid), MasterCard (credit, debit and prepaid), Visa (credit, debit and prepaid) and American Express cards issued by Australian banks. The Australian Competition and Consumer Commission, which was given new powers on 25 February 2016, will enforce the ban in conjunction with the Reserve Bank of Australia. The ACCC's excessive surcharging ban has applied to large businesses since September last year. For its part, the RBA has indicated, as a guide, that the costs to merchants of accepting payment by debit cards is in the order of 0.5 per cent. Accepting credit card payments costs between one and 1.5 per cent, but accepting American Express cards costs around two to three per cent. The ACCC noted in its media release on the topic yesterday that businesses should have received merchant statements from their financial institutions in July, setting out their cost of acceptance for each payment method.For businesses intending to set a single surcharge across multiple payment methods, the ACCC has warned that the surcharge must be set at the level of the lowest cost method, not an average of all acceptance rates.That is, to avoid being fined or prosecuted, businesses can surcharge only what it actually costs them to process card payments, including bank fees and terminal costs. For example, if a business's cost of acceptance for Visa Credit is 1.5 per cent, the surcharge on Visa Card payments cannot exceed 1.5 per cent. Meanwhile, the ACCC has found some merchants have incurred higher costs than these but any surcharge level imposed by merchants cannot be higher than the costs incurred by them for accepting that payment method.The ban does not affect businesses that choose not to apply a surcharge to payments.The RBA's website also provides detailed information for businesses about its standard, including how businesses can identify and quantify those costs that can be passed on to a consumer as a surcharge.Payment types that are not covered by the ban include BPAY, PayPal, Diners Club cards, American Express cards issued directly by American Express, cash and cheques.