Embodiments of the present invention address deficiencies of the art in respect to instant messaging and provide a method, system and computer program product for instant messenger subset management. In an embodiment of the invention, an instant messenger subset management method can be provided. The method can include selecting a set of names for different open chat sessions of an instant messenger, providing a single responsive posting to the selected set, and persisting the set for subsequent processing. Additionally, the method can include annotating the single responsive posting in a chat log to indicate the names in the selected set having received the single responsive posting.