We’ve Reached Peak Voice

Woman looking at her phone in surprise

This article originally appeared in Telegeography

It’s true that 2015 marked a turning point in the international voice market—the first time since the Great Depression that international call traffic declined. However, that slump in voice traffic has turned into a rout, as carriers’ traffic fell a further 8.4 percent in 2017 to 484 billion minutes.

Graph of International Voice Traffic 1998-2018
What Goes Up Must Come Down International Voice Traffic 1998-2018

Going Over the Top

The same transition to mobile and social calling that drove a 20-year boom in voice traffic has left the industry uniquely vulnerable to the rise of mobile social media.


Both WhatsApp and Facebook Messenger topped 1.3 billion monthly active users in 2018, and WeChat is not far behind, with just over 1 billion active users in September 2018.


TeleGeography estimates that just seven communications apps—WhatsApp, Facebook Messenger, WeChat, QQ, Viber, Line, and KakaoTalk—combined for over 5 billion monthly users in September 2018. These estimates exclude apps for which directly comparable data is unavailable, including Apple’s FaceTime, Google Hangouts, and Skype (the latter two of which have over 1 billion downloads from Google’s App Store).

Calculating OTT’s Impact

TeleGeography has fairly reliable estimates of Skype’s traffic through 2013, when the company carried 214 billion minutes of on-net (Skype-to-Skype) international traffic.

GRaph of Carrier and OTT Traffic 1998-2018
OTT Delivering More Minutes Every Year Carrier and OTT Traffic 1998-2018

This calculation suggests that cross-border OTT traffic overtook international carrier traffic in 2016, and would reach nearly 952 billion minutes in 2018, far exceeding the 450 billion minutes of carrier traffic projected by TeleGeography.


Telcos terminated 547 billion minutes of international traffic in 2013, and Skype plus carrier traffic totaled 761 billion minutes. If we assume that total international—carrier plus over-the-top (OTT)—traffic has continued to grow at a relatively modest 13 percent annually since 2013, the combined volume of carrier and OTT international traffic would have expanded to 1.24 trillion minutes in 2017, and to 1.40 trillion minutes in 2018.

Want to know more? Take a closer look at the source—the recently-updated TeleGeography Report and Database.