The Slack vs Microsoft Teams pricing debate is one of the most misunderstood comparisons in enterprise software, because the headline numbers ignore the most important factor: most organizations that use Microsoft Teams are already paying for it as part of a Microsoft 365 subscription. The marginal cost of Teams for a Microsoft 365 subscriber is zero. The marginal cost of Slack for the same organization is $8.75–$15.00 per user per month.
That framing doesn’t mean Teams is always the right answer — there are significant product differences that justify the Slack premium for many organizations. But the pricing comparison only makes sense with full context.
Slack Pricing 2025: Every Plan
Slack’s current plan structure:
- Free: 90-day message history limit (changed from the previous 10,000-message cap in 2023), 10 app integrations, 1:1 audio and video calls only. Genuinely useful for small teams evaluating the product, but the 90-day history limitation makes it impractical for organizations that need message archives for compliance, search, or institutional memory.
- Pro: $8.75/user/month (annual). Unlimited message history, unlimited app integrations, group audio and video calls (up to 50 participants), and Slack AI (recently included). For a 50-person team: $437.50/month, $5,250/year.
- Business+: $15/user/month (annual). Adds SSO (SAML), compliance exports for message history (essential for regulated industries), and 24/7 support. For a 200-person organization: $3,000/month, $36,000/year.
- Enterprise Grid: Custom pricing. Multi-workspace organization management, enterprise security controls, data residency, and DLP integration. Typically starts at $17.50+/user/month for large deployments; large enterprises with 1,000+ users often negotiate into the $12–$16/user/month range through volume agreements.
Salesforce’s acquisition of Slack in 2021 has resulted in progressively deeper integration between Slack and the Salesforce platform — Slack is now a core interface for Salesforce workflows, customer case collaboration, and Einstein AI interactions. For Salesforce-heavy organizations, this integration creates genuine value that has no equivalent in Teams.
Microsoft Teams Pricing: What It Actually Costs
Microsoft Teams is not sold as a standalone product in the way Slack is. It’s included in the following Microsoft 365 plans, among others:
- Microsoft 365 Business Basic ($6/user/month): Teams included
- Microsoft 365 Business Standard ($12.50/user/month): Teams included
- Microsoft 365 Business Premium ($22/user/month): Teams included
- Microsoft 365 E3 ($36/user/month): Teams included
- Microsoft 365 E5 ($57/user/month): Teams included
The marginal cost of Teams for an organization on any of these plans is zero — Teams is a feature of the bundle, not an additional purchase. This is the most important number in the Slack vs Teams pricing comparison: the effective cost of Teams for Microsoft 365 subscribers is $0/user/month.
Microsoft also offers Teams Essentials as a standalone product at $4/user/month for organizations that want Teams without a full Microsoft 365 subscription — but this is primarily relevant for organizations without Microsoft 365 that want basic Teams functionality.
The Real Comparison: What You Actually Get for the Money
At an organization that already pays for Microsoft 365 Business Standard ($12.50/user/month), adding Slack Pro costs an additional $8.75/user/month — an 70% increase in their per-user software cost for collaboration tools alone. That’s the decision most organizations are actually making, and the product comparison needs to be honest about what justifies that premium.
Where Slack genuinely outperforms Teams:
- Search and message findability: Slack’s search is meaningfully better than Teams’ for finding historical conversations across channels. Power users who rely heavily on historical message retrieval consistently rate Slack superior.
- Channel organization and workflow: Slack’s channel model, huddles (lightweight audio calls), and workflow builder are more refined and more intuitively used by development and design teams accustomed to the product.
- Third-party integration breadth: Slack’s app directory has 2,600+ integrations. For engineering teams that live in GitHub, Linear, PagerDuty, Datadog, and other developer tools, Slack’s integration density is meaningfully better than Teams’.
- Salesforce integration: If your CRM is Salesforce, the native Slack-Salesforce integration provides workflows, deal room collaboration, and Einstein AI interactions that have no Teams equivalent.
- Developer and startup culture fit: This is soft but real. Slack carries cultural gravity in engineering and startup communities that Teams doesn’t. Top candidates in engineering roles often mention tool preference, and forcing a migration from Slack to Teams in an engineering organization can create meaningful retention friction.
Where Teams has the advantage:
- Cost for Microsoft 365 organizations: If you’re paying for M365, Teams is free. At scale, this is a very large number.
- Native Microsoft integration: Calendar integration with Outlook, native SharePoint file collaboration, direct integration with Word/Excel/PowerPoint, and Azure AD authentication are all native and seamless in Teams. In Slack, these require integrations that work but feel more bolted-on.
- Meeting capabilities: Teams is genuinely excellent for larger meetings, webinars, and town halls — categories where Slack Huddles are not a direct replacement. Teams Phone (additional license) replaces desk phones, creating an integrated telephony and video conferencing platform that Slack doesn’t attempt to be.
- Compliance for regulated industries: Teams’ compliance center integration with Microsoft Purview is mature and well-suited to financial services, healthcare, and government organizations. Slack Business+ includes compliance exports, but Teams’ depth in regulatory compliance tooling is greater for organizations with complex requirements.
The 200-User Decision: What the Numbers Actually Mean
For a 200-person company on Microsoft 365 Business Standard:
- Current M365 spend: 200 × $12.50/month = $2,500/month, $30,000/year (includes Teams at $0 marginal cost)
- Adding Slack Pro: 200 × $8.75/month = $1,750/month, $21,000/year additional
- Adding Slack Business+: 200 × $15/month = $3,000/month, $36,000/year additional
Is Slack worth $21,000–$36,000/year over the Teams that’s already included? For a consumer-facing tech company where engineering culture and Salesforce integration are central concerns, potentially yes. For a professional services firm where Microsoft ecosystem integration is the priority and the team uses Outlook heavily, almost certainly no.
The organizations that should pay for Slack are the ones where the specific Slack advantages — developer tool integration, Salesforce workflow, or established cultural adoption — generate value that Teams genuinely cannot match. The organizations that should use Teams are the ones where the M365 integration value and zero marginal cost make Teams the rational choice, and where the productivity difference between the two platforms is small relative to the price difference.