Ribbon Communications to Report First Quarter 2022 Financial Results on April 27, 2022

April 13, 2022

Plano, TX – Ribbon Communications Inc. (NASDAQ: RBBN), a global provider of real time communications software and IP optical transport solutions to service providers, enterprises, and critical infrastructure sectors, today announced that it will report financial results for the first quarter of 2022 after the close of the market on Wednesday, April 27, 2022. Following the release, Ribbon Communications will host a conference call with the financial community at 4:30 p.m. ET to discuss the results.

The Company will offer a live, listen-only webcast of the conference call via the investor section of its website at investors.ribboncommunications.com, where a replay will also be available shortly following the conference call.

Conference call details

Date: Wednesday, April 27, 2022

Time: 4:30 p.m. ET

Dial-in number (Domestic): 877-407-2991

Dial-in number (International): 201-389-0925

Instant Telephone Access: Call me™

Replay information:

A telephone playback of the call will be available following the conference call until May 11, 2022 and can be accessed by calling 877-660-6853 or 201-612-7415 for international callers. The reservation number for the replay is 13727656.

About Ribbon

Ribbon Communications (NASDAQ: RBBN) delivers communications software, IP and optical networking solutions to service providers, enterprises and critical infrastructure sectors globally. We engage deeply with our customers, helping them modernize their networks for improved competitive positioning and business outcomes in today’s smart, always-on and data-hungry world. Our innovative, end-to-end solutions portfolio delivers unparalleled scale, performance, and agility, including core to edge software-centric solutions, cloud-native offers, leading-edge security and analytics tools, along with IP and optical networking solutions for 5G. To learn more about Ribbon visit rbbn.com.

APAC, CALA & EMEA Press

Catherine Berthier

+1 (646) 741-1974

cberthier@rbbn.com

North America Press

Dennis Watson

+1 (214) 695 2224

dwatson@rbbn.com

Investor Relations

+1 (978) 614-8050

ir@rbbn.com

Analyst Relations