Slack is asking you to assemble an agent stack from other vendors.
In June alone Slack bolted on three separate things (MCP, native Claude, a $3.6B Fin acquisition), each its own license and security review. Microsoft 365 Copilot is one agent at 20M seats, on the identity and data you already govern.
The AI customers want is already running inside Teams.
Microsoft 365 Copilot reached 20 million paid enterprise seats by April 2026, with engagement Microsoft compares to Outlook, meaning for most large customers, Teams-native AI is deployed and in daily use before Slack's Agentforce can even land.
One suite for meetings, calling, chat and files, at enterprise meeting scale.
Teams carries full-scale video (300-participant meetings, webinars to 1,000) plus calling, files and compliance in the same Microsoft 365 license, where Slack is still primarily messaging and tops out at 50 on a huddle. For an org already on M365, that's capability they own versus a second tool to buy.
On June 23, 2026 Anthropic and Salesforce launched Claude Tag, embedding Claude (running on Opus 4.8) as a native, multiplayer agent inside Slack channels that anyone can summon by typing @Claude to delegate tasks, build context over time and work asynchronously. It replaces the prior standalone Claude in Slack app, with administrators able to opt into migration within 30 days, and ships in beta to Claude Enterprise and Team organizations.
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On June 17, 2026 Slack made Slackbot's Model Context Protocol (MCP) client generally available and launched a partner ecosystem of more than 20 third-party apps (including Amplitude, Atlassian, Box, Canva, Docusign, Linear, Miro, Notion and Zoom) that users drive from one Slackbot conversation. This turns Slackbot from a chat-bound assistant into a vendor-neutral orchestration layer over a customer's existing app stack, the same job Microsoft pitches as Teams' all-in-one suite, except Slack unifies tools the customer already owns rather than replacing them. Several pieces ship later (Notion, PagerDuty, Adobe and Tableau Next are listed coming soon, and native Block Kit rendering is not yet live), so today's GA is the routing layer plus the first wave of live apps.
On June 15, 2026 Salesforce signed a definitive agreement to acquire Fin (formerly Intercom) for about $3.6 billion, adding a packaged customer-service AI agent that resolves on average 76% of support volume end-to-end and runs natively across channels including Slack. The deal reinforces Agentforce (which Salesforce says hit $1.2B ARR in Q1 FY27) and is expected to close in Q4 of Salesforce's fiscal 2027 (early 2027), so it is a buy-not-build escalation of Slack's agent story rather than a capability shipped in Slack today.
Salesforce's Summer '26 release (generally available June 15, 2026) makes Slack the default, auto-provisioned collaboration platform for every new Enterprise and Unlimited org: a fully configured Slack workspace and CRM-connected Salesforce channels are created automatically with no separate purchase or setup, and Chatter is turned off by default for new orgs, structurally mirroring Microsoft's Teams-in-Microsoft-365 bundling and removing Slack as a separate procurement decision inside Salesforce's 150,000+ customer base.
Bank of America reinstated Salesforce (CRM) at Underperform with a $160 target on May 18, 2026 (against a ~$268 consensus and a stock down ~33% YTD) on the bear case that AI agents erode Salesforce's per-seat model. So what for Teams: Slack's parent is under visible financial and investor pressure, undercutting any 'Slack-plus-Salesforce is the safe platform bet' pitch.
Slack now ships a native lightweight CRM. Launched in spring 2026 and included in the Business+ plan at no extra cost, Slack CRM lets small teams track leads, deals and contacts inside Slack by asking Slackbot, while a Salesforce engine stores the data in the background. On July 1, 2026 Salesforce began rolling it out to small businesses across Asia Pacific markets including Singapore and the Philippines. It extends Slack from a messaging app toward a bundled operating system for work, and hands Salesforce a free CRM on-ramp that upsells into the full platform with no data migration.
On April 1, 2026 Salesforce CEO Marc Benioff publicly projected Slack revenue of about $3 billion this year (a company claim, not an audited figure, and not broken out in Salesforce filings). So what for Teams: probe the number's verifiability and counter with Microsoft's audited M365 commercial growth.
On March 31, 2026 Salesforce unveiled an AI-heavy makeover of Slack: about 30 new features repositioning Slackbot as an agent that routes work across Agentforce and thousands of apps. So what for Teams: Slack is attacking Copilot's 'AI work hub' narrative head-on; counter with Copilot's reach across all of Microsoft 365, not just chat.
Salesforce made the agentic Slackbot generally available to Business+ and Enterprise+ customers on January 13, 2026, putting AI agents on by default in Slack's paid tiers. So what for Teams: enterprise Slack accounts now ship with agentic AI, so Copilot for Teams must demo comparable depth and Microsoft 365 data grounding in head-to-head deals.
Slack CEO Denise Dresser left in December 2025 to become OpenAI's chief revenue officer, with chief product officer Rob Seaman stepping in on an interim basis. So what for Teams: Slack's leadership is in transition exactly as enterprises commit to multi-year AI platform bets, a fair stability question to raise.
In mid-2025 Salesforce changed Slack's API terms to bar bulk data export and to prohibit using Slack data to train LLMs, cutting off third-party AI tools such as Glean. So what for Teams: position Microsoft Graph as a more open, permission-respecting path for customers who want to bring their own AI to their messaging data.
Slack suffered a near-two-hour global outage on May 12, 2025, caused by a database routing misconfiguration that blocked messaging and core features worldwide. So what for Teams: a concrete reliability counterpoint to keep ready when Slack challenges Teams on uptime.
Microsoft Teams ships inside every Microsoft 365 business subscription (from Business Basic at $7 per user per month as of July 1, 2026) as an included app, giving it near-frictionless distribution to hundreds of millions of M365 seats. Adopting Slack means standing up and paying for a second tool.
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Salesforce positions Slack as 'the operating system for work' and Slackbot as the conversational front door to enterprise AI agents: its explicit counter to Microsoft Copilot, and the frame a Teams rep will meet in Salesforce-centric accounts.
Microsoft Teams list pricing effective July 1, 2026: Teams Essentials stays at $4.00 per user per month, while Microsoft 365 Business Basic rose from $6 to $7, Business Standard from $12.50 to $14, Microsoft 365 E3 from $36 to $39, Microsoft 365 E5 from $57 to $60 and Microsoft 365 F3 from $8 to $10 per user per month, with Teams included in all of these suites.
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Slack list pricing: Pro $8.75/user/month billed monthly (or $7.25 annual), Business+ $18 monthly (or $15 annual), Enterprise+ custom; the free tier caps message history at 90 days. The page also currently shows a temporary 50%-off promo on monthly plans.
Competitive Battlecard5 across 3 zones›
The AI customers want is already running inside Teams.
Best for Exec / top-downMicrosoft 365 Copilot reached 20 million paid enterprise seats by April 2026, with engagement Microsoft compares to Outlook, meaning for most large customers, Teams-native AI is deployed and in daily use before Slack's Agentforce can even land.
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One suite for meetings, calling, chat and files, at enterprise meeting scale.
Best for Economic buyerTeams carries full-scale video (300-participant meetings, webinars to 1,000) plus calling, files and compliance in the same Microsoft 365 license, where Slack is still primarily messaging and tops out at 50 on a huddle. For an org already on M365, that's capability they own versus a second tool to buy.
The agent race is genuinely contested. Don't wave it away.
Best for Technical evaluatorOn June 17, 2026 Slack made Slackbot's MCP client generally available, connecting 20-plus third-party apps (Amplitude, Atlassian, Box, Canva, Docusign, Linear, Miro, Zoom and others) from a single Slackbot conversation. Slack positions this as vendor-neutral orchestration over the customer's existing stack, the same job Teams pitches as an all-in-one suite, but letting customers keep tools they already own rather than replace them. Several integrations (Notion, PagerDuty, Adobe, Tableau Next) and native Block Kit rendering are still coming, so GA today is the routing layer plus a first wave of live apps. For Salesforce-centric teams, Agentforce agents add CRM-aware context on top of this. Microsoft counters with Copilot wired across Teams, Office and Power Platform, with 20 million paid enterprise seats in daily use as of April 2026. Whoever already runs the customer's core systems usually wins the AI on top of them.
Slack Connect is a real external-collaboration moat.
Best for Exec / top-downSlack has long cited 77 of the Fortune 100 using Slack Connect to work across company lines, and those external webs are sticky: if a prospect's partners and clients all live in Slack, that's genuine switching friction Teams has to work around with federation and guest access. (Slack's own figure, and several years old. Concede the network effect, not the exact number.)
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Slack still owns developer mindshare and the deepest app ecosystem.
Best for Eng-led championSlack's marketplace and integration culture run deep (Salesforce touts AI-enabled Slack apps growing 690% year over year), and developer-heavy teams genuinely prefer its extensibility and feel. Here, Teams has to earn the seat.
Sentiment5 signal›
Sentiment: Slack is rated #1 for business instant messaging in G2's Winter 2026 report at 4.5/5, edging Teams (~4.4) on day-to-day user satisfaction, a small but persistent gap reflecting Slack's messaging UX.
Sentiment: users complained Teams' meeting controls were cluttered enough to cause accidental screen-shares, a gripe serious enough that Microsoft publicly acknowledged it in May 2026. Microsoft has since shipped the fix: a redesigned toolbar with center-aligned controls, a separated Leave button and a two-step share confirmation, rolling out to Targeted Release users in early July 2026 and reaching worldwide general availability in early September 2026.
Sentiment: users repeatedly find Teams' channels clunky and hard to navigate, with many defaulting to plain chat instead, a recurring confusion about where conversations belong.
Sentiment: Slack's free-tier 90-day message-history cap is a frequent reviewer frustration, making older conversations hard to retrieve and nudging teams toward paid plans.
Sentiment: Slack drew developer-community backlash in September 2025 after threatening to deactivate teen-coding nonprofit Hack Club's 11-year message history unless it paid $200,000/year; the CEO publicly apologized and reversed course, but the episode dented Slack's developer-friendly image.
Objection Handling7 objections›
"Regulators say you only beat Slack by illegally bundling Teams. And Slack is suing you again."
Raised by Security & regulatedIt's a fair point: the EU made Microsoft unbundle Teams and widen the price gap, and Slack filed a fresh UK suit in April 2026 over tying. Microsoft accepted binding commitments rather than fight, including selling Microsoft 365 without Teams and letting customers export their Teams data.
"Isn't Teams slow and a memory hog?"
Raised by Technical evaluatorMicrosoft itself acknowledged the older client could use up to a gigabyte of RAM at idle and felt sluggish in calls, so the complaint has real history. Don't deny it. The fix shipped in early 2026, moving calling into its own process.
"You're raising prices to push Copilot AI we didn't ask for."
Raised by Economic buyerAs of July 1, 2026 M365 list prices are up: Business Basic $6 to $7, Business Standard $12.50 to $14, E3 $36 to $39, E5 $57 to $60 and F3 $8 to $10 per user per month, bundled with additions like Defender for Office 365 Plan 1 on E3, expanded Intune and richer Copilot Chat. Standalone Teams and Copilot SKUs are excluded from the change, and the suites folded in real added value, not just an AI tax.
"Can I trust Microsoft on security after Storm-0558 and Midnight Blizzard?"
Raised by Security & regulatedDon't minimize it: the US Cyber Safety Review Board called Microsoft's security culture inadequate after the 2023 Exchange breach. Microsoft's answer is the Secure Future Initiative and shipping more security capability into E3/E5 by default.
"Our developers just prefer Slack. It's more usable."
Raised by Eng-led championOften true, and worth conceding: users rate Slack's search and integration experience highly, and engineering teams like its feel. That's a genuine preference, not a misunderstanding.
"Teams went down globally in December. How can we rely on it?"
Raised by Security & regulatedAcknowledge it: Teams had worldwide disruptions in late 2025 with message delays, tracked openly in the admin center. Microsoft backs M365 with a financially-backed 99.9% uptime SLA and publishes incident reviews.
"Isn't Teams' meeting UI cluttered enough to cause accidental screen-shares?"
Raised by Eng-led championThat was a real complaint, serious enough that Microsoft publicly acknowledged it. The fix is now dated and shipping: center-aligned controls with a separated Leave button and a two-step share confirmation, reaching Targeted Release users in early July 2026 and worldwide general availability in early September 2026.
Cut Log9 removed / revised›
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| slack | ai-product-relaunch | 2026 | recent_moves | 2026-03-31 | 2026-06-05 | false |
| slack | revenue-run-rate | 2026 | recent_moves | 2026-04-01 | 2026-06-05 | false |
| slack | flagship-product | slackbot-ga | recent_moves | 2026-01-13 | 2026-06-05 | false |
| slack | key-departure | ceo-2025 | recent_moves | 2025-12-10 | 2026-06-05 | false |
| slack | api-data-restriction | 2025 | recent_moves | 2025-06-11 | 2026-06-05 | false |
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| microsoft-teams | copilot-adoption | current | battlecard | 2026-04-29 | 2026-06-05 | false |
| microsoft-teams | differentiator | all-in-one-video | battlecard | 2026-04-27 | 2026-06-05 | false |
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| slack | differentiator | slack-connect | battlecard | 2022-04-01 | 2026-06-05 | false |
| slack | differentiator | app-ecosystem | battlecard | 2026-06-05 | 2026-06-05 | false |
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| microsoft-teams | sentiment | channels-usability | sentiment | 2025-09-28 | 2026-06-05 | false |
| slack | sentiment | free-tier-limit | sentiment | 2026-03-05 | 2026-06-05 | false |
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| microsoft-365 | objection | price-increase | objection_handling | 2026-07-01 | — | false |
| microsoft | objection | security-breach | objection_handling | 2024-04-03 | 2026-06-05 | false |
| slack | objection | user-preference | objection_handling | 2026-04-27 | 2026-06-05 | false |
| microsoft-teams | objection | reliability-outage | objection_handling | 2025-12-20 | 2026-06-05 | false |
| slack | distribution | salesforce-bundled-default | recent_moves | 2026-06-11 | 2026-06-11 | false |
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| slack | ai-integration-claude-tag | recent_moves | 2026-06-23 | 2026-06-24 | false |
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