A cross border payment charge and a currency conversion charge are different. A payment can be international even when the customer and merchant use the same currency, depending on the provider's definition and the locations involved.
Read the provider's classification Check how the product identifies domestic and international transactions. Card issuer location, merchant location and payment method can matter. Do not assume that charging a foreign customer in the merchant's currency makes the transaction domestic.
Model the main customer markets Break sales into the actual regions and payment methods expected. Apply the relevant published rates or agreed quote. If international sales are a large share of turnover, a domestic headline fee is a poor estimate of the overall cost.
Avoid hidden customer friction Customers may also face charges from their own issuer. Clear currency display helps, but the merchant cannot promise that every issuing bank will apply no additional fee.
For example, a Hong Kong company charging a European issued card in euros may still encounter a cross border classification under the processor's terms. Settlement conversion is a separate question.
Review the effective cost in provider reports and investigate unexpected categories. Before changing the legal or operational structure to reduce fees, consider the wider compliance and administrative consequences. A small payment cost saving does not by itself justify a company arrangement that the business cannot properly maintain.
Sources and scope
General information, not advice for your individual legal or tax position. Confirm current requirements with the relevant authority or provider.