To solve the problem of an off-line terminal unit judges that a credit card is valid in succession, even if it is valid when the terminal unit receives data and invalid procedures are done after that to continue sale because the terminal unit can perform sales processings at a high speed within a scope of balance, without conducting communication each time a customer buys goods by storing valid/invalid card information of the customer buying goods using the card and the balance in a terminal unit body.

The number of communication destination sending out data and customer number are stored on a card data concentrated management base side to monitor the customer's valid/invalid card information, and when the card turns invalid, it is informed to the stored communication destination to immediately inhibit sale on a terminal unit side.