Techniques for message deduplication are described. In one embodiment, an apparatus may comprise a client front-end component operative to receive an incoming message at a messaging system from a messaging client on a client device; extract a deduplication token from the incoming message; store the incoming message in a message queue where examining the deduplication token determines that the incoming message does not duplicate any existing message of the messaging system; and discard the incoming message where examining the deduplication token determines that the incoming message does duplicate an existing message; and a message deduplication component operative to examine the deduplication token to determine whether the incoming message duplicates any existing message of the messaging system. Other embodiments are described and claimed.