A method, system and program for tracking user availability are provided. Time estimates of a user availability are compiled for a separate user from among multiple users for participation in a messaging session. Then, the compiled time estimates of user availability are specified for output to at least one other user from among the multiple users, such that the at least one other user is enabled to track user availability for the separate user. In particular, compiled time estimates may be specified according to graphical, audio, video, or textual output preferences for the at least one other user. In addition, the compiled time estimates may be specified according to a current time zone for the at least one other user.