The present invention provides a computer-implemented method, system, tool, and program product for sending a customized reply to an instant message. Specifically, under the present invention, a customized message may be provided for a specific instant messaging contact/availability status combination. When the availability status is selected and a message is received from the instant messaging contact, the customized message is automatically sent to the messaging contact. The invention may also be integrated into a calendaring application to determine, for example, whether the message recipient is in a meeting and, if so, to automatically send a reply that gives an estimated ending time for the meeting.