The Avaya Definity 8403 phone enhanced design and functionality make it an excellent phone for any business. The multiline digital terminal is an ideal solution for Definity system customers who need flexible yet economical call-handling capabilities throughout their business. The Avaya 8403 terminal multiple line appearances provide expanded call coverage and other advanced voice communications.

For example – one-touch access to dedicated feature buttons such as Conference, Hold, Mute, and Transfer lets your employees work faster and more efficiently. The rocker-type Volume Control easily adjusts the ring, handset, or speaker volume, and the red LED Message waiting light instantly alerts users to messages. The Feature button allows quick access – via the dialpad – to 12 additional features of the telephone system.

In addition, the listen-only, built in Speaker provides convenient off-hook dialing and listening.


  • 3 programmable call appearance/feature buttons
  • 8 fixed feature buttons
  • Listen-only speakerphone

System Requirements/Compatibility:

  • 2-wire TN2181 16-ports circuit card for DEFINITY G3V2 Systems and higher
  • 2-wire TN2224 24-ports circuit card for DEFINITY Release 5.0 and higher
  • 4-wire TN754C circuit card for System 75 and earlier DEFINITY communications systems