Framing the Comparison
Slack and Microsoft Teams dominate the enterprise communication market. Choosing between them is rarely simple — pricing structures differ, integration libraries overlap, and performance varies by use case. This comparison uses a standardized feature matrix and documented metrics rather than brand preference to guide the decision.
Pricing Comparison (Per User / Month, Billed Annually)
| Tier | Slack | Microsoft Teams |
|---|---|---|
| Free | 90-day message history, 10 integrations | Unlimited messages, 5GB storage |
| Entry Paid | ~$7.25 (Pro) | ~$6.00 (Essentials) |
| Business | ~$12.50 (Business+) | ~$12.50 (Microsoft 365 Business Basic) |
| Enterprise | Custom pricing | Custom pricing |
Note: Microsoft Teams is often bundled with Microsoft 365, which can shift the effective cost significantly depending on your existing subscriptions.
Feature Matrix
| Feature | Slack | Microsoft Teams |
|---|---|---|
| Native Video Calling | ✓ (up to 50 participants, free tier) | ✓ (up to 1,000 participants) |
| Threaded Messaging | ✓ (core feature) | ✓ (per-channel threads) |
| App Integrations | 2,600+ apps | 700+ apps |
| Workflow Automation | Workflow Builder (no-code) | Power Automate integration |
| Document Co-editing | Via Google Docs / third-party | Native Office 365 co-editing |
| Channel Organization | Channels + Sections | Teams + Channels + Tabs |
| Guest Access | ✓ (paid tiers) | ✓ (all tiers) |
| Search Capability | Full-text, advanced filters | Full-text, Microsoft Graph powered |
Where Slack Wins
Integration Breadth
Slack's 2,600+ app integrations give it a significant lead for teams using diverse third-party tools — especially in engineering, product, and marketing contexts. Connecting GitHub, Jira, PagerDuty, Salesforce, and dozens of niche SaaS tools is natively supported without workarounds.
Developer Experience
Slack's API is well-documented and mature. Building custom bots and internal integrations is faster and requires less boilerplate than the Teams equivalent. This is a measurable advantage for organizations with technical teams building internal tooling.
Where Microsoft Teams Wins
Microsoft 365 Ecosystem Integration
If your organization already uses Word, Excel, SharePoint, and Outlook, Teams integrates at the OS and application level in ways Slack simply cannot replicate. Live document co-editing within the Teams interface, calendar sync with Outlook, and SharePoint file storage are natively embedded — not bolted on.
Video Call Scale
Teams supports up to 1,000 participants in a single call versus Slack's 50. For large organizations running all-hands meetings or webinars, this is a hard ceiling that makes Slack impractical without a separate video platform.
Performance Notes
Both applications are Electron-based on desktop, which creates similar memory footprints. Reported RAM usage under normal workflows typically ranges from 400MB–800MB for both platforms. Neither has a clear performance edge on modern hardware, though Teams has historically received more criticism for sluggishness on older machines.
Verdict: Decision Framework
- Choose Slack if: You need maximum integration flexibility, strong developer tooling, or your team uses primarily non-Microsoft SaaS tools
- Choose Microsoft Teams if: You're embedded in the Microsoft 365 ecosystem, need large-scale video calls, or want to consolidate licensing under one vendor