Slack and Microsoft Teams dominate workplace communication. Both offer messaging, video calls, file sharing, and integrations, but they approach the problem differently. Your choice often comes down to your existing tech stack and how your team prefers to work.
Overview
Slack launched in 2013 and quickly became the default communication tool for startups and tech companies. It is known for its clean interface, powerful search, and extensive integration ecosystem. Salesforce acquired Slack in 2021.
Microsoft Teams launched in 2017 as part of the Microsoft 365 suite. It has grown rapidly, especially among enterprises already using Microsoft products. Teams combines chat, video conferencing, file storage, and app integrations into a single platform.
Key differences
User interface
Slack's interface is clean and focused. Conversations happen in channels, and the sidebar keeps everything organized. Teams packs more functionality into its interface — channels, chats, files, apps, and calendar are all accessible from the left rail, which can feel cluttered but also means fewer context switches.
Messaging experience
Slack's messaging experience is widely considered superior. Threads are intuitive, search is fast and accurate, and the overall feel is responsive. Teams has improved its messaging significantly, but threads can still feel awkward and search occasionally misses results buried in different tabs.
Video and audio calls
Teams has the stronger video conferencing feature set. It supports up to 1,000 participants in meetings (10,000 for view-only), offers background effects, breakout rooms, live captions, and recording. Slack added Huddles for quick audio calls and integrates with Zoom or Google Meet for larger meetings, but its native video is limited.
File sharing and storage
Teams integrates deeply with SharePoint and OneDrive, giving you robust file management, co-authoring, and version history. Slack stores files in conversations but does not offer the same document management capabilities — you typically link to files in Google Drive or Dropbox.
Integrations
Slack offers over 2,600 integrations in its app directory and is known for excellent third-party connectivity. Teams has a growing app ecosystem and benefits from seamless integration with Microsoft 365 apps like Word, Excel, PowerPoint, Planner, and Power BI.
Pricing comparison
| Feature | Slack Free | Slack Pro | Teams Free | Teams Essentials | Microsoft 365 Business Basic | |---------|-----------|-----------|------------|-----------------|----------------------------| | Monthly cost | $0 | $8.75/user/mo | $0 | $4/user/mo | $6/user/mo | | Message history | 90 days | Unlimited | Unlimited | Unlimited | Unlimited | | File storage | Limited | 10 GB/user | 5 GB/user | 10 GB/user | 1 TB/user | | Video calls | 1:1 only | 50 people | 60 min, 100 people | 30 hrs, 300 people | 30 hrs, 300 people | | Integrations | 10 | Unlimited | Limited | Limited | Full M365 suite |
Pros and cons
Slack
Pros:
- Superior messaging and threading experience
- Excellent search across conversations
- Largest third-party integration ecosystem
- Clean, intuitive interface
- Great for developer and tech-focused workflows
Cons:
- Native video conferencing is limited
- File management is basic
- Can get expensive at scale
- Free tier now limits message history to 90 days
Microsoft Teams
Pros:
- Deep integration with Microsoft 365
- Strong video conferencing capabilities
- Included with many Microsoft 365 plans (effectively free)
- Better file management through SharePoint/OneDrive
- Enterprise-grade security and compliance
Cons:
- Interface can feel cluttered and slow
- Threading is less intuitive than Slack
- Search can be inconsistent
- Resource-heavy desktop app
- Notification management can be confusing
When to use each
Choose Slack if:
- Your team values a clean, fast messaging experience
- You rely heavily on third-party integrations
- You are a startup, tech company, or developer team
- You already use Google Workspace or other non-Microsoft tools
- Threaded conversations are important to your workflow
Choose Teams if:
- Your organization already uses Microsoft 365
- Video conferencing is a core part of your workflow
- You need enterprise compliance and security features
- You want to minimize the number of separate tools
- Budget is a concern and you have existing Microsoft licenses
Verdict
Slack remains the better pure messaging tool with a smoother user experience and stronger integrations. Microsoft Teams is the better all-in-one platform, especially if your organization already pays for Microsoft 365.
For most enterprises with existing Microsoft licenses, Teams is the practical choice — you are already paying for it. For teams that prioritize communication quality and use diverse tooling, Slack is worth the investment. The right answer depends less on features and more on your existing ecosystem.