Best Self-hosted Communication & Collaboration tools in 2026

PHP-based groupware and CRM for teams: calendars, contacts, email, file management, projects and CRM with CalDAV/CardDAV/IMAP support and extensible modules.

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Microsoft Exchange Online+15

Community-focused server for private photo/video backup, albums, chat and audio/video calls with mobile app support and S3-compatible storage.

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Google Photos+10

Create, share and combine structured tables and views inside Nextcloud. Supports templates, CSV/spreadsheet import, custom columns, filtered views and an OpenAPI-backed A...

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Google Sheets+8

An IRC network implementation in Go that uses the Raft consensus algorithm to eliminate netsplits and provide transparent client failover via a bridge.

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IRCCloud+3

Open-source, modular SIP server (proxy, presence, conference, B2BUA) with push gateway, ICE/STUN/TURN, MySQL/SQLite support; optimized for mobile and embedded systems.

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3CX+11

Open-source event listing and aggregator built on Laravel. Provides iCal feeds, tags, RSVP, photos, and multiple authentication methods for community and organization eve...

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Meetup+6

SAMA is a Node.js-based open-source chat server using uWebSockets.js, MongoDB and Redis, providing WebSocket/HTTP APIs, E2EE, clustering, and web/mobile clients.

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Sendbird+19

Atria is an AGPL-3.0 open-source platform for managing hybrid events, sessions, sponsors, and real-time attendee networking with chat and discovery tools.

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Whova+16

Open-source PWA that generates live captions and transcripts in the browser; supports broadcasts, OBS/vMix integration, and optional Azure AI captions.

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Rev+6

Integrated installer and platform for home infrastructure. Provides VPN relay for NAT traversal, preconfigured email, automatic HTTPS, reverse proxy, and a web management...

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Cloudron+19

Python-based Discord bot that lets authorized users list and control Docker containers and images via Discord commands, using the host Docker socket.

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Carl-bot

Open-source PHP groupware providing CalDAV/CardDAV, ActiveSync, email client, CRM, tasks, file manager and Docker images for on-premise collaboration.

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Microsoft Exchange Online+19

Prosody IM is a modern, resource-efficient XMPP (Jabber) server written in Lua, designed to be easy to configure and extend for private messaging and federation.

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Cisco Jabber+19

Open-source, API-first platform for carrier-grade IP communications: VoIP, WebRTC, messaging, conferencing and programmable telephony microservices.

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3CX+19

Collabora Online Development Edition (CODE) provides a self-hosted LibreOffice-based online editor for documents, spreadsheets and presentations for testing or small team...

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Collabora Online+13

Exim is an open source SMTP message transfer agent (MTA) for Unix-like systems, offering flexible mail routing and extensive controls for handling inbound email.

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Amazon Simple Email Service (Amazon SES)+10

Postorius is a Django web UI for managing GNU Mailman 3 mailing lists, covering list administration and user subscription preferences.

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Groups.io

A lightweight, curl-first free/busy scheduler that syncs availability from a CalDAV calendar and can send iCal booking invites via SMTP.

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Calendly+11

A single-binary, low-resource Matrix homeserver in Rust; simple setup, RocksDB (default) or SQLite backends, built with axum and Ruma.

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Element Matrix (Hosted)+19

HyperKitty is a web interface and archiver for Mailman 3 mailing lists, providing searchable list archives, thread views, user profiles, and email interaction features.

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Cryoserver Email Archive

Salut à Toi (SàT) is a self-hostable, XMPP-based communication suite with web, desktop, and CLI frontends, supporting chat and collaborative features via plugins.

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Element Matrix (Hosted)+13

Inboxen provides unlimited unique email inboxes to protect your primary address from spam, sign-ups, and tracking while keeping your real inbox clean.

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Mailinator+3

Schleuder is an OpenPGP-enabled mailing list manager that encrypts list mail and supports remailing, allowing subscribers and non-subscribers to exchange secure emails vi...

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Groups.io+3

Modular, PHP/JavaScript web GUI that configures and manages Asterisk PBX features, endpoints, and call routing for businesses and service providers.

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3CX+11

OpenTalk is an open-source video conferencing platform offering GDPR-compliant SaaS and self-hosted deployments with features like recording, whiteboards, breakout rooms,...

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Zoom+18

Continuwuity is a fast, lightweight Matrix homeserver written in Rust, focused on stability, performance, and improved Matrix specification compliance for federation.

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Element Matrix (Hosted)+6

Open-source webmail and groupware offering email, contacts, calendar, cloud drive, tasks, notes and an admin control panel for multi-tenant email services.

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Microsoft Exchange Online+18

OpenSMTPD is an open-source, minimal SMTP daemon from the OpenBSD project providing an RFC-compliant MTA with privilege separation, table backends, filters and TLS suppor...

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Postfix+11

Carrier-grade VoIP softswitch/SBC for routing, billing, and managing SIP traffic, with LCR, fraud control, and high-availability deployment options.

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PortaSwitch (PortaOne)+5

Self-hosted collaborative music room app with DJ queues, real-time chat, and YouTube/SoundCloud-style playback for shared listening sessions.

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Turntable.fm+3