Microsoft Teams

Judgement

What it is

Complete system

What it does

Chat, meetings, calls and file collaboration built on Microsoft 365, with SharePoint behind team files and optional phone system.

Adopt it when

Your business already pays for Microsoft 365 and wants chat and video meetings without another vendor.

Watch out

The client is heavy and the chat experience is clumsier than Slack; in the EU it is now sold separately from some Microsoft 365 plans.

Ready for

Production-ready

Runs as

Cloud service, desktop app and mobile app

What the license allows

Closed source: you use it under the maker's terms and cannot change or resell the code.

Judged on 2026-11-03 from the maker's description and Wikipedia. The license and age lines are worked out directly.

Compare Microsoft Teams

Open-source alternatives to Microsoft Teams

1. 1
   Zulip zulip

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   Complete system Production-ready Your team finds Slack threads chaotic and wants organised, asynchronous conversations, self-hosted or hosted.

   ★ 26k Apache-2.0 Python Active, pushed today
2. 2
   Element-web element-hq

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3. 3
   Chat tinode

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   Complete system Usable You want to embed or run your own messaging service with ready clients.

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5. 5
   Quiet TryQuiet

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   Complete system Experimental A small group values running chat with no server at all and accepts missing features compared with Slack.

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6. 6
   Colanode colanode

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   Complete system Experimental A small team wants chat and docs together on its own server with offline support.

   ★ 5.2k Apache-2.0 TypeScript Slowing, pushed 7 months ago
7. 7
   Raven frappe

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   Complete system Usable Your company runs ERPNext or other Frappe apps and wants chat inside the same system.

   ★ 839 AGPL-3.0 TypeScript Active, pushed today

Every alternative to Microsoft Teams

Other commercial team chat apps

1. 1
   Discord Discord Inc.

   American online communication software

   Complete system Production-ready You run a public or semi-public community, such as gamers, an open-source project or a creator audience.

   42k readers a month Since 2015 Commercial
2. 2
   Slack Salesforce, Inc.

   Boost productivity and save time with Slack‌ – ‌the AI work platform for managing projects, automating workflows and connecting teams securely. Start working smarter today.

   Complete system Production-ready A team wants the chat tool with the widest integration ecosystem and is willing to pay per seat.

   8.4k readers a month Since 2013 Commercial
3. 3
   Google Chat Google

   Learn how Google Chat helps individuals, groups and businesses to connect and collaborate online with secure messaging and powerful features from Google Workspace.

   Complete system Production-ready Your company runs on Google Workspace and wants basic team chat that is already included.

   2.5k readers a month Since 2017 Commercial

Under it

Every program, Microsoft Teams included, runs on a microchip.

How compilers were built, back to punched paper tape