Can Microsoft 365 replace Slack?
On capability, yes — Microsoft 365 covers team chat properly rather than partly. Dropping Slack would save $36.25 a month at five people. Whether you should is a question about your team, not about features.
What you are comparing
| People | Microsoft 365 Business Basic | Slack Pro | Paying both |
|---|---|---|---|
| 1 | $7 | $7.25 | $14.25 |
| 3 | $21 | $21.75 | $42.75 |
| 5 | $35 | $36.25 | $71.25 |
| 10 | $70 | $72.50 | $142.50 |
| 25 | $175 | $181.25 | $356.25 |
You are already paying for team chat inside Microsoft 365. The question is not whether Slack is good — it is whether the difference between the two is worth $36.25 a month to you.
The capability question is settled
Microsoft 365 covers team chat as a first-class feature, not as a token one. If your reason for keeping Slack is that the suite cannot do this, that reason does not hold.
So what actually decides it
Three things, none of which appear on a feature comparison:
- Whether your team will actually move. This is the one that sinks most consolidations. A tool people like and a tool people tolerate are not interchangeable at equal feature parity, and a migration your team quietly ignores leaves you paying for both anyway.
- What leaves with it. Message history, shared files, integrations other people built. Export before you cancel, not after — we have not verified what Slack does with your data on cancellation, which is a gap in our research rather than reassurance.
- Who outside your company uses it. Clients and contractors in shared channels or folders are a real switching cost, and one you cannot schedule.
What we are not saying
Cancel it. We have not run either product in a lab, we do not know how your team works, and the cost of a migration nobody wanted is reliably higher than the subscription it saves. This page exists to put a number and a specific trade-off in front of a decision that usually gets made on vague feelings about duplication — in either direction.
If you are looking at this across a whole stack rather than one pair, the stack auditor prices everything you pay for and flags every capability more than one of your tools claims.
Other replacement questions
- Can Google Workspace replace Calendly?
- Can Google Workspace replace Docusign?
- Can Google Workspace replace Dropbox?
- Can Google Workspace replace Jotform?
- Can Google Workspace replace SignWell?
- Can Google Workspace replace Slack?
Tell me when either price changes
We re-check Microsoft 365 and Slack weekly. If either rate moves, the arithmetic on this page changes — and you hear about it with the date and the source.