Slack vs Microsoft Teams in 2026: An Honest Comparison

Slack has 42 million daily active users. Microsoft Teams has 320 million. That gap tells you a lot about distribution — Teams comes bundled with Microsoft 365, so most companies using Word and Excel get it for "free." But user count doesn't mean Teams is better. It means Microsoft is better at bundling.

The real question is which one fits how your team actually works. After a major Slack pricing overhaul in June 2025 and Microsoft's continued Copilot push, the comparison has shifted significantly. Here's where things stand in early 2026.

Pricing compared

Big pricing shift in June 2025: Slack killed the standalone AI add-on ($10/user/mo) and bundled AI features into every paid plan. Business+ went from $12.50 to $15/user/mo annual to absorb this. The net effect: Slack AI is now "free" with your plan, while Copilot costs $30/user/mo on top of your Teams license.

For a 50-person team on annual billing:

• Slack Pro: $4,350/year (AI included)
• Slack Business+: $9,000/year (full AI included)
• Teams Essentials: $2,400/year (no AI)
• M365 Business Basic: $3,600/year (no AI)
• M365 Business Basic + Copilot: $21,600/year (AI included)

If AI matters to you — and it increasingly does — Slack is significantly cheaper for messaging AI.

Messaging and channels

Both platforms are built around channels (Slack) or teams/channels (Teams). The core messaging experience is similar: threads, reactions, file sharing, search, mentions.

Where Slack wins: The messaging UX is snappier and more responsive. Search is faster and more accurate. Slack Connect lets you create shared channels with external organizations — invaluable for agencies, partners, and client work. The Canvas feature (collaborative documents within channels) is more intuitive than Teams' Loop components. Message formatting and emoji reactions feel more polished.

Where Teams wins: Unlimited, searchable chat history on the free plan. Slack's free plan now hides messages older than 90 days and permanently deletes data after 1 year. SharePoint-backed storage gives 1TB per user on paid plans (Slack offers 10-20GB). Loop components sync across Teams, Outlook, and Word, which is powerful if your workflows span Office apps.

Video calling

This isn't close. Teams wins video calling by a wide margin.

Slack Huddles are designed for spontaneous, informal conversations — like walking over to someone's desk. They're not meant for client presentations, all-hands meetings, or recorded sessions. If video calling is a significant part of your workflow, you'll need Zoom, Google Meet, or another tool alongside Slack. Teams handles everything natively. The April 2026 licensing update moved advanced webinar features (up to 3,000 interactive + 10,000 view-only participants) into core Teams Enterprise licenses.

AI features

This is where the 2025 pricing changes made the biggest difference.

Slack AI (included in Pro and Business+):

• Channel and thread summaries
• Huddle notes (auto-generated after every call)
• Search answers that synthesize information across conversations
• Translation, file summaries, and AI workflow generation (Business+)
• New AI-powered Slackbot agent (Business+, rolling out 2026) — a personal AI that uses your messages, files, channels, and connected tools
• Enterprise+ exclusive: cross-app search across Salesforce, Google Drive, GitHub, Jira, and more

Microsoft Copilot ($30/user/mo add-on, or $21 promo through March 2026):

• Meeting summaries with speaker attribution and action items
• Chat summaries of unread messages (rolling out May 2026)
• AI Workflows for scheduled automated prompts
• Content generation across Word, Excel, PowerPoint, and Outlook
• GPT-5.2 with "Quick Response" and "Think Deeper" reasoning modes
• Teams Mode: @copilot in any group chat for AI assistance
• Real-time content analysis of shared screens (coming August 2026)

Copilot is more powerful — it works across the entire Office suite, not just messaging. But at $30/user/mo, a 50-person team pays $18,000/year for AI on top of their Teams license. Slack bundles comparable messaging AI at no extra cost. The key question: do you need AI in Word and Excel, or just in chat?

Integrations

Slack has 2,600+ apps in its marketplace with 750,000+ custom bots deployed across all workspaces. Teams has roughly 1,400-2,000 apps via AppSource plus deep Power Platform integration.

Slack advantage: Developer-friendlier API with simpler custom bot creation. More third-party integrations, especially for dev tools (GitHub, Jira, Linear, Datadog, PagerDuty). The Salesforce integration is native and deep (Salesforce owns Slack since 2021) — CRM records, deal coordination, revenue forecasting, and Agentforce AI agents all work within Slack channels.

Teams advantage: Native Microsoft 365 integration is unmatched. Power Automate creates enterprise workflows without code. Power BI dashboards embed in channels. SharePoint document libraries, Planner task boards, and Loop components all live natively in Teams. Microsoft Graph API enables deep custom integrations across the entire Microsoft ecosystem. If your stack is Microsoft-centric, nothing comes close.

Security and compliance

Teams has a clear edge for regulated industries. FedRAMP authorization across multiple security levels, Intune device management, and Azure AD conditional access policies give enterprise IT teams the granular control that Slack can't match without Enterprise Grid (custom pricing). For healthcare, government, and financial services, this often makes the decision.

Mobile and desktop experience

Both apps work on iOS and Android. Slack is lighter and faster — the app loads quicker and consumes less RAM. Teams is feature-richer but heavier, with high memory usage being a persistent complaint on both desktop and mobile.

App Store ratings tell a mixed story: Slack at 3.7/5 on iOS (21K reviews) and 4.4/5 on Android (127K reviews). Teams at roughly 3.8/5 on iOS and 4.2/5 on Android. Neither is winning awards for mobile experience, but Slack's is less frustrating for quick messaging throughout the day.

On desktop, the performance gap is more noticeable. Slack typically uses 300-500MB of RAM with 4-5 workspaces open. Teams regularly consumes 800MB-1.2GB — sometimes more when running background processes for calendar sync, presence detection, and OneDrive integration. Microsoft shipped a rebuilt Teams client in late 2024 (based on WebView2 instead of Electron), which improved startup time by about 50% and reduced memory usage by roughly 30%. It's better than it was, but Slack still feels snappier for pure messaging workflows.

File management on desktop also differs significantly. Teams surfaces SharePoint document libraries directly in channels, making co-editing Office files seamless. Slack's file handling is simpler — drag, drop, preview — but lacks native document collaboration. You'll need Google Docs, Notion, or another tool for real-time co-editing within Slack.

Who should pick what

Pick Slack if:

• Your team is primarily tech, developer, or startup culture
• You use Salesforce (native integration is unmatched since the acquisition)
• You collaborate with external partners or clients (Slack Connect)
• AI on a budget matters (bundled in all paid plans)
• Third-party integrations are critical (GitHub, Jira, Linear, Figma, Datadog)
• You value messaging speed and UX over video features

Pick Teams if:

• You already pay for Microsoft 365 (Teams is effectively free)
• Video meetings are a daily part of work (recording, breakout rooms, webinars)
• You're in a regulated industry needing FedRAMP, HIPAA, or device management
• Your team lives in Word, Excel, and PowerPoint
• Budget is your primary concern (Essentials at $4/user beats Slack Pro at $7.25)
• You need 300+ person meetings or webinars

Pick both if:
Some organizations use Teams for company-wide meetings and document collaboration, and Slack for team chat and developer workflows. It sounds wasteful, but if your company has both Microsoft 365 subscriptions and a strong engineering culture, running both can actually reduce friction.

FAQ

Is Teams really free?
The standalone free plan exists with unlimited chat, 60-minute group calls, and 5GB storage. But most organizations get Teams through Microsoft 365 Business Basic ($6/user/mo), which adds 1TB storage, meeting recording, and web Office apps. Calling it "free" is technically true but misleading — you're usually paying for it through your Microsoft subscription.

Did Slack get cheaper or more expensive in 2025?
Both. Pro dropped from $8.75 to $7.25 annual (cheaper). Business+ increased from $12.50 to $15 annual (more expensive). But Business+ now includes all AI features that previously cost $10/user/mo extra. If you were paying for Slack + AI, it's cheaper overall. If you weren't using AI, it's pricier.

Can I migrate from Slack to Teams (or vice versa)?
You can export Slack workspace data (JSON format) and Teams supports data import, but the migration is messy. Message history transfers, but channels, integrations, custom bots, and workflow automations need to be rebuilt from scratch. Most organizations run both in parallel for 2-3 months during transition. Budget at least a month of overlap.

Which is better for a company under 20 people?
Slack Pro ($7.25/user annual) if chat, integrations, and developer tools matter most. Microsoft 365 Business Basic ($6/user) if you need Office apps, video meetings, and 1TB storage. The $1.25/user difference is less important than which ecosystem your existing tools live in.

What about the market share gap?
Teams' 320 million vs Slack's 42 million users is mostly a distribution story — Teams comes free with Microsoft 365. In tech and startup communities, Slack remains dominant. Market share doesn't determine which tool is better for your specific team.

Compare Slack and Teams with other collaboration tools on Toolradar. Explore our team communication category for more options.