- "Member Address is the Flash Mail address you can only access in The World."
- — Orca —
A player's Member Address (メンバーアドレス, Menbā Adoresu) is their unique identifier in The World and The World R:2. This address is used for basic communications, including Flash Mail, as well as some minor offline communication. Most importantly, however, it is used for inviting others to join in a party and venture into The World.
In The World R:2, Member Addresses also list a player's online or offline status. Players who are online but do not wish to be bothered can also list their member address as "busy".
- Sora from .hack//SIGN collected the Member Addresses of female players as a hobby.
- Kite gains a total of 20 Member Addresses in the original four games.
- Including IYOTEN and Asta, who are only temporary party members, Haseo gains a total of 23 Member Addresses in the .hack//G.U. games.