Consider Slack when…
Shortlist Slack when you work closely with outside companies in shared channels, use many third-party apps, or are not on Microsoft 365.
Explore Slack alternativesFIND YOUR FIT
Slack vs Microsoft Teams
Slack vs Microsoft Teams: compare standalone per-user chat with chat included in Microsoft 365 by licensing, files, meetings, and guests.
The decision in brief
The decision often comes down to what you already pay for. Teams is licensed with qualifying Microsoft 365 plans or on its own, and each team gets SharePoint storage, a shared mailbox, and a calendar. Slack is priced per active user and is built around channels, apps, and Slack Connect for working with other companies.
A focused editorial selection based on the linked official documentation. Fit notes are our judgment, rather than firsthand benchmark results or a universal ranking. How we select and verify information.
Compare the working details
| Decision factor | Slack | Microsoft Teams |
|---|---|---|
| Main focus | Organising team conversations into channels, and working with partners and customers in shared channels. | Organisations already on Microsoft 365 that want chat, meetings, and files under the same identity and admin controls. |
| Working setup | Create a workspace, set up channels for teams and projects, invite members and guests, then add apps and workflows from the directory. | Assign Teams licences in the Microsoft 365 admin centre, create teams and channels, then turn on guest access if people outside the organisation need to join. |
| Pricing model | A free plan shows 90 days of message and file history, allows up to ten apps, and deletes data older than one year. Paid plans are priced per user per month, and you are billed only for members who were active in the last 28 days, with prorated credit for inactive ones. | Teams is licensed as part of qualifying Microsoft 365 plans or as a standalone subscription, including Teams Essentials for small businesses. Teams Premium is a paid add-on for advanced meeting, protection, and AI features. |
| What to verify | On the free plan, group huddles are not available and anything older than a year is deleted; review your workspace analytics before downgrading. | Check whether your Microsoft 365 plan includes Teams or needs a separate Teams licence, and which meeting features sit in the Premium add-on. |
Which belongs on your shortlist?
Consider Microsoft Teams when…
Shortlist Microsoft Teams when you already license Microsoft 365, want meetings and SharePoint files in one place, and manage identity in Microsoft Entra ID.
Run the same evaluation in both
- Create the same project channel in each, share a file, edit it together, and find it again a day later.
- Invite an external guest to each and note what they can see and do.
- Price both for your number of active users, counting any Microsoft 365 licences you already pay for.
Try the same task before you choose
Run one launch week in a shared channel
Use the same fictional setup in each candidate. A seven-person product team at a fictional company, Brightwell, is launching a feature. They need a #launch channel, a private #leads channel, and one external contractor who should see #launch only. Use test accounts and invented messages, never real customer data.
Every check starts as Not run. Record your own observations; these are evaluation criteria, rather than completed product tests. Your worksheet stays in this page and can be downloaded.
| Task and expected observation | Slack | Microsoft Teams |
|---|---|---|
| Create #launch and the private #leads channel Members see #launch; only the three leads can find and read #leads. | ||
| Invite the external contractor The contractor can read and post in #launch but cannot see #leads or browse other channels. Record the plan this needs. | ||
| Run two discussions at once in #launch Replies stay attached to the right discussion, and a member who was away can catch up on each separately. | ||
| Start a quick audio call with screen sharing Three members join from the channel without scheduling; record any participant limit on your plan. | ||
| Post an update from an incoming webhook or bot A fictional build-status message appears in #launch with a link, and you can mute it without leaving the channel. | ||
| Search for a message and a file from the start of the week, then export the channel Both are found, and the export includes messages and files in a format you could import elsewhere. | ||
| Price the setup for seven members and one guest Record the plan these checks need and the monthly and yearly cost, including any suite you already pay for. |
0 of 14 checks have an observation. An observation does not imply a passed test.
Sources and check dates
Provider documentation supports the product and billing descriptions. Confirm current limits and terms before choosing a plan.
ShowMeYourSaaS also offers commercial product coverage. These guides follow our editorial selection criteria; placement is not a purchased ranking. Send a correction with the page and a supporting source.