Two days ago, Microsoft has introduced the Microsoft Teams in a free version that available in 40 languages.
The free version of Microsoft Teams will include support for up to 300 people, with unlimited chat messages and search. Microsoft is including most of the Microsoft Teams features you’d expect, with some limits to push people towards an Office 365 subscription. The free version includes built-in audio and video calling for groups, and even unlimited app integrations for adding apps like Trello to Microsoft Teams. Microsoft is even enabling guest access so anyone can join a free Microsoft Teams server. Microsoft is also limiting team file storage to 10GB, with 2GB of personal storage for each member. Below are some features for Microsoft Teams free version:

  • Available in 40 languages
  • Up to 300 people.
  • Unlimited chat messages and search.
  • Built-in audio and video calling for individuals, groups, and full team meetups.
  • 10 GB of team file storage plus an additional 2 GB per person for personal storage.
  • Integrated, real-time content creation with Office Online apps, including built-in Word, Excel, PowerPoint, and OneNote.
  • Unlimited app integrations with 140+ business apps to choose from—including Adobe, Evernote, and Trello.
  • Ability to communicate and collaborate with anyone inside or outside your organization, backed by Microsoft’s secure, global infrastructure.

Compared with Slack, Slack’s free version is limited to 10,000 searchable messages, 10 app integrations, 5GB of file storage, no guest accounts, and only 1:1 video chats.
In my opinion, Microsoft Teams free version is fair enough for small business or a new startup that needs a communication tool with collaboration feature.

source: Microsoft Teams Blog