Best Self-hosted Communication & Collaboration tools in 2026

CryptPad is an end-to-end encrypted collaboration suite with real-time editors, file storage, and sharing, designed to keep document contents private from servers and adm...

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Google Workspace+12

Mailu is a full-featured mail server distributed as Docker images, providing SMTP/IMAP/POP3, webmail, administration UI, and built-in security and anti-spam features.

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Microsoft Exchange Online+19

Open source webmail client for IMAP with address book, search, folders, and a customizable UI via plugins and skins.

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Zimbra Collaboration+11

Spacebar is an open source, self-hostable Discord-compatible communication platform with text chat, voice, and video, designed to work with existing clients and bots.

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Discord+19

ejabberd is an Erlang/OTP-based messaging server providing XMPP chat and presence, MQTT broker capabilities for IoT, and SIP services for real-time communications.

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CloudMQTT+11

SimpleLogin is an open-source email alias service that lets you create aliases to protect your real inbox, forward mail, and reply or send from aliases using custom domai...

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SimpleLogin+3

Self-hostable online office suite for viewing and collaboratively editing documents, spreadsheets, presentations, PDFs, and forms with strong OOXML compatibility.

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ONLYOFFICE Docs Cloud+13

Self-hosted web-based IRC client with multi-user support, persistent connections, and a responsive UI for desktop and mobile.

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The Lounge Cloud+3

Go-based, modular mail server implementing SMTP/LMTP/IMAP with built-in DKIM/SPF/DMARC, storage backends (SQLite/Postgres/S3), Prometheus metrics and Docker support.

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Microsoft Exchange Online+10

Haraka is a fast, event-driven SMTP server for receiving, filtering, and relaying email, featuring a modular plugin architecture for customization at scale.

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Postfix+11

All-in-one secure mail server with SMTP, IMAP, webmail, automatic TLS (ACME), and built-in SPF/DKIM/DMARC plus junk filtering for low-maintenance domains.

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Microsoft Exchange Online+19

FreeSWITCH is an open-source software-defined telecom stack for building VoIP and real-time communication services with SIP and WebRTC support.

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Twilio+15

Open-source, local-first Slack and Notion alternative combining team chat, rich docs, databases, and file management with offline-first sync and self-hosting.

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Notion+19

Open-source anonymous email forwarding that creates and manages aliases, supports custom domains, encrypted forwarding, and self-hosting via Postfix and MariaDB.

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Addy.io (AnonAddy)+3

Lightweight CalDAV/CardDAV server for syncing calendars, to-dos, and contacts with many clients, storing data on the filesystem and supporting auth and TLS.

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Google Calendar+8

Synapse is a Matrix homeserver implementation for running federated, secure real-time chat and collaboration on your own infrastructure.

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Element Matrix (Hosted)+19

Tailchat is an open source team chat and collaboration platform with a strong plugin system, bot integrations, multi-group workspaces, and RBAC permissions.

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Slack+14

Modoboa is an open source mail server management platform with a modern web UI, integrating Postfix and Dovecot with admin tools, webmail, calendar, and address book.

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Microsoft Exchange Online+16

Converse.js is an open-source, client-side web XMPP/Jabber chat app that can run standalone or be embedded into sites, with group chat and OMEMO encryption.

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IRCCloud+19

Ergo is a modern IRC server (ircd) written in Go, with integrated account management, history storage, bouncer-like features, and strong IRCv3 support.

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IRCCloud+12

Open-source PBX and telephony toolkit for building communications applications; modular C-based engine with SIP, WebRTC, RTP, ARI/AMI APIs and hardware support.

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3CX+19

Baïkal is a lightweight CalDAV/CardDAV server with a web admin UI for managing users, calendars, and address books, backed by MySQL or SQLite.

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Google Calendar+4

An open-source WebRTC SFU that routes media for scalable multiparty video conferencing; supports Colibri XMPP/REST control, DTLS/SRTP, and Prometheus metrics.

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LiveKit Cloud+17

Openfire is an open source XMPP (Jabber) server for real-time messaging and collaboration, with a web admin console and a plugin ecosystem.

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Cisco Jabber+15

Prebuilt Nextcloud appliance and management tools for Raspberry Pi, Odroid, VMs and LXC; includes Apache, PHP, MariaDB, Redis, web panel and backup utilities.

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Google Drive+17

Open-source Debian-based OS and control panel that simplifies installing, managing and securing web apps, mail and services via a web admin and app catalog.

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Cloudron+19

Stoat is an open-source, self-hostable chat platform for communities and teams, offering text channels, permissions, moderation tools, and a web app.

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Discord+13

Kamailio is an open source SIP signaling server for scalable VoIP and real-time communication platforms, supporting routing, load balancing, WebRTC, and IMS/VoLTE.

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AudioCodes Mediant Session Border Controller (SBC)+6

Tox is a decentralized, peer-to-peer communication system for encrypted messaging, voice/video calls, screen sharing, and file transfers without central servers.

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Signal+12

Stoat (formerly Revolt) is an open-source chat platform for communities and teams with channels, direct messages, roles/permissions, moderation tools, and bot support.

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Discord+11