The e-mail system includes a responsible person terminal holding a plurality of recipient addresses to which given e-mail is sent, and a reference list editor terminal connected to the responsible person terminal through a network for editing a reference list comprising one or more recipient addresses to be updated from among the recipient addresses. The reference list includes recipient addresses to be replaced, recipient addresses to be deleted, and recipient addresses to be added. The reference list end a program or tool that references the reference list to update an e-mail recipient address list are recorded/stored on a server. The reference list editor terminal and the responsible person terminal access the server to cause the update function to be performed.