Top 30 Free Instant Messaging Software for Teams Collaboration

Popular team chat with channels, direct messages, file sharing, and integrations; free tier supports up to 10k recent messages.

Chat, video calls, and file collaboration integrated with Office Online; free plan includes unlimited chat messages and 2 GB per user storage.

Voice‑enabled community platform with persistent text channels, screen sharing, and robust permission controls.

Open‑source self‑hosted chat offering unlimited users, real‑time translation, and extensive customization.

Self‑hosted open‑source messaging with threaded conversations, file sharing, and enterprise‑grade security.

Topic‑based chat that keeps conversations organized; free cloud tier supports unlimited users and public streams.

Threaded, distraction‑free messaging designed for asynchronous collaboration; free plan includes unlimited messages.

Team messenger with channels, video calls, and integrated task management; free plan supports up to 10 k messages per month.

Simple chat with AI‑powered search and unlimited messages for small teams (up to 10 users).

Decentralized, end‑to‑end encrypted messenger built on the Matrix protocol; free hosted service available.

Cloud‑based messaging with large group support (up to 200 k members), bots, and file sharing up to 2 GB.

Privacy‑focused messenger offering encrypted group chats, disappearing messages, and cross‑platform support.

Integrated with Google Workspace; provides direct messages, rooms, and bots for seamless collaboration.

Classic Microsoft chat and video platform supporting group calls, screen sharing, and file transfers.

Simple group messaging app from Meta, ideal for quick coordination and media sharing.

Combines chat, task management, and workflow automation; free plan allows up to 6 users.

Secure collaboration tool with encrypted messaging, voice/video calls, and file sharing.

Decentralized, peer‑to‑peer messenger with end‑to‑end encryption and no central server.

Open‑source, encrypted, peer‑to‑peer messaging and video chat platform.

Chat for developers and open‑source communities; integrates with GitHub and GitLab.

Enterprise‑style social network with groups, chat, and video calls; free tier offers basic features.

Team messaging with channels, bots, and file sharing; free plan supports up to 100 users.

All‑in‑one collaboration suite featuring chat, video calls, task management, and document storage for up to 12 users.

Team inbox with threaded conversations, integrations, and unlimited public messages.

Team messaging with persistent chat, file sharing, and task lists; free plan includes unlimited users.

Secure team chat with channels, voice/video calls, and screen sharing; free plan supports up to 10 users.

Hybrid email‑chat platform offering searchable threads, file sharing, and integrations; free plan includes unlimited users.

Encrypted messaging combined with file sharing and Git repositories; free and open‑source.

Open‑source, self‑hosted chat with high configurability, role‑based access, and extensive plugin ecosystem.

Hosted version of Rocket.Chat offering unlimited users, public channels, and basic integrations at no cost.

Deploy your own Matrix server for full control over data, security, and custom branding.