BITNET Relay, also known as the Inter Chat Relay Network, was a chat network setup over BITNET nodes. It predated Internet Relay Chat and other online chat systems. The program that made the network possible was called "Relay" and was developed by Jeff Kell of the University of Tennessee at Chattanooga in 1985 using the REXX programming language.

This system drew its name from "relay race" which shares a comparable behavior, where messages travel hop-by-hop along the network of Relay servers until they reached their destination. Messages sent within the United States would take a few seconds to reach their destinations, but communication times varied in other countries or internationally. If one or more network links were down, BITNET would store and forward the messages when the network links recovered, minutes or even hours later.