Rocket.Chat

Rocket.Chat started in 2015 as an open-source project and grew into a full communications platform used by over 12 million users, including governments, NGOs, and companies that want chat without surrendering their data. It's more ambitious than a Slack clone — it blends internal team chat with customer-facing omnichannel support.

What Makes Rocket.Chat Special

It's open-source and self-hostable, like Mattermost, but it casts a wider net. Beyond internal channels and DMs, Rocket.Chat includes an omnichannel inbox that pulls in WhatsApp, Telegram, email, SMS, and website live chat — so your support team and your internal team work in the same tool. It also supports federation via the Matrix protocol, meaning users on different Rocket.Chat (or Matrix) servers can message each other across organizational boundaries.

End-to-end encryption is available for sensitive channels. The platform is highly themeable and extensible through apps and a REST API, and the on-premise option appeals to privacy-first and regulated organizations.

Day-to-Day Experience

The core chat experience is familiar — channels, threads, mentions, reactions, voice and video. The mobile apps are decent. Where it gets busy is the admin side: the sheer number of settings and modules can overwhelm a small team that just wants a chat app.

The Honest Trade-offs

Flexibility cuts both ways. Setup and administration are more involved than Slack, and the UI, while functional, feels less polished. Self-hosting means you handle upgrades and scaling. Some users report performance issues on large servers without careful tuning. The free Community edition is generous, but enterprise features like advanced compliance, SSO bundles, and engagement dashboards sit behind paid tiers.

Who Should Choose Rocket.Chat

Privacy-conscious organizations, governments, NGOs, and companies that want internal chat plus customer omnichannel support in one self-hostable platform. If you need federation across organizations, or you specifically want end-to-end encryption you control, Rocket.Chat is one of the few options that delivers all of it.