Telegram, an online instant messaging service popular among adherents of the Islamic State (IS), remains vital to the organization’s ecosystem of communications. The platform’s functional affordances, paired with relatively lax enforcement of Telegram’s terms of service (ToS), offers IS sympathizers a user-friendly medium to engage with like-minded supporters and content.

This report examines 636 pro-IS Telegram channels and groups that contain English-language content collected between June 1, 2017 and October 24, 2018. While this time-bound and linguistically limited sample represents a sliver of the pro-IS ecosystem on Telegram, the subsequent findings have important implications for policymakers assigned to the dual tasks of countering IS’ online foothold and engaging with service providers like Telegram.