The Avaya 2400 series adds several enhancements over previous generations of digital telephones. These include paperless button labeling, local call log and speed dial directories and streamlined styling consistent with Avaya IP telephones. There are currently three models in the 2400 series: the entry-level 2402 Digital Telephone, the mid-level 2410 Digital Telephone, and the high-performance 2420 Digital Telephone.

The Avaya 2402 is a cost effective two-wire digital telephone, for many office applications. It is designed to complement the 2410 mid-level and 2420 executive telephones. The 2402 has a 2-line x 24-character display with two label-less call appearances, a Listen-Only Speaker, 10 Fixed Feature Keys: Conference, Transfer, Drop, Redial, Speaker, Message, Hold, Mute, Volume Up & Down, and Feature (to access 12 additional dial pad features). The 2402 is Hearing Aid Compatible, has a Message Waiting Indicator that flashes when ringing, eight Personalized Ring Patterns and is either desk or wall mountable.

The Avaya 2410 is a flexible display telephone with several capabilities such as local call log and speed dial not available on previous generations of digital telephones. It has a 5 x 29 display with 12 label-less call appearances (in two screens), full-duplex speakerphone, 14 fixed feature keys, four softkeys, 12 shifted feature buttons, large message waiting indicator, headset jack, local language customization, eight Personalized Ring Patterns and is either desk or wall mountable.

The Avaya 2420 Digital Telephone sports an array of convenient features, while supporting expansion capabilities and effective integration with current infrastructure investments. This telephone provides a large-scale display for easy viewing and call control with 24 call appearance/feature buttons. Administration and ongoing maintenance is simplified as the switch automatically performs key/button labeling. This eliminates the time-consuming and laborious task of using paper labels to denote phone features, and reduces costs when moving phones among users or offices. Online access to electronic downloads gives near-instant access for key product upgrades and feature enhancements as they occur. Additional features such as call logging and a speed-dial directory help enhance overall productivity by giving users the tools needed for more effective call tracking and faster outbound calling capabilities.