To deliver information relating to the balance of a credit payment account on the internet, and to pay/transfer a shortage.

A service site 3 receives account transfer data from a credit company terminal 4. If an account transfer data processing portion 33 determines that the balance of the credit payment account is smaller than the total payment amount of this month, a mail edit processing portion 35 prepares a notice including the data of 'a balance shortage' on the basis of the data from the account transfer data processing portion 33, and sends the notice to a user terminal 2 through the internet. When a user opens an electronic mail and clicks on 'a automatically paying/transferring button', a paying/transferring processing portion 34 sends a paying/transferring screen to the user terminal 2. Application of automatically paying/transferring is interactively conducted, so that the process of paying/transferring the shortage from a paying/transferring source account to the credit payment account is carried out. Therefore, the user can use a credit card without worrying about the balance of the account.