To provide an electronic transaction account system which enables a seller to grasp the purchase history of a specific purchaser and which is capable of preventing the unnecessary leakage of purchaser's personal information.

A settlement server 23 in which the electronic transaction account system is constructed is provided with a settlement processor 230, an account file 231 of purchaser's own name and an electronic transaction account file 232. When the processor 230 receives a settlement request, the purchaser name and the account number of the corresponding account of the purchasers name are retrieved from the file 232 on the basis of a net name and a net account number. Transaction history, a balance, etc., are collated from the file 231 on the basis of the purchaser's name and account number of the account of the purchaser's name, and at the time of judging the possibility of payment, the transfer of a prescribed amount is reported to a seller's server and the completion of the transfer is reported to a purchaser's terminal.