A surcharge, in payments, is an additional fee that a merchant adds to the price when a customer chooses to pay by card, usually to recover the merchant's cost of accepting that card. The practice is covered fully in the main entry on card surcharging. In general business language, surcharge can mean any extra charge, such as a fuel surcharge on freight, so the card sense is usually clear from context.
Card surcharges are tightly controlled. Card networks set rules on whether and how merchants may surcharge, often capping the fee at the merchant's actual cost and requiring clear disclosure before payment. Laws differ widely: the European Union bans surcharges on consumer cards covered by its interchange caps, the United Kingdom bans surcharges on consumer card payments, and US rules vary by state, while Australia allows surcharges but limits them to the cost of acceptance.
A surcharge differs from a cash discount, which lowers the price for customers who pay by other means, and from a convenience fee charged for an alternative payment channel. Merchants that surcharge must also account for regulated cards and debit cards, which are often excluded, and for the full merchant discount rate they actually pay.