Rimeto
2020
Why
Employee directory and org-chart software.
Impact
Added richer employee profiles and people search to Slack.
Outcome
Integrated into Slack profiles and search.
Slack Technologies, LLC
Enterprise CollaborationFounded 2009- HQ today: San Francisco, California, United States
Reviewed by Swet Parvadiya
Company data updated: October 2026
Acquisitions
Slack Acquisitions
4
Major Deals Covered
What are Slack's biggest acquisitions?
This page covers 4 major deals from 2015 to 2020, each with its price where disclosed and the reason behind it.
- Major deals covered
- 4
- First deal
- 2015
- Most recent
- 2020
| Company | Year | Price | Purpose |
|---|---|---|---|
| Rimeto | 2020 | Undisclosed | Employee directory and org-chart software. |
| Astro Technology | 2018 | Undisclosed | AI-assisted email and calendar app. |
| Missions (from Robot & Pencil) | 2018 | Undisclosed | Workflow-building tool for Slack. |
| Screenhero | 2015 | Undisclosed | Collaborative screen-sharing and voice app. |
- What companies has Slack bought?
- Major acquisitions by Slack documented here include Rimeto (2020), Astro Technology (2018), Missions (from Robot & Pencil) (2018) and Screenhero (2015).
- What is Slack's most recent acquisition?
- The most recent Slack acquisition documented here is Rimeto, in 2020.
Astro Technology
2018
Why
AI-assisted email and calendar app.
Impact
Brought machine-learning and productivity engineers into Slack.
Outcome
Astro app shut down; team joined Slack.
Missions (from Robot & Pencil)
2018
Why
Workflow-building tool for Slack.
Impact
Informed the design of Slack Workflow Builder.
Outcome
Folded into Workflow Builder.
Screenhero
2015
Why
Collaborative screen-sharing and voice app.
Impact
Added screen sharing and calling technology.
Outcome
Fed into Slack calls and later Huddles.
Slack Technologies, LLC's Growth & Acquisition Strategy
Slack's growth strategy has three parts: sell Slack with Salesforce's CRM and Agentforce products to existing Salesforce customers; make Slackbot and enterprise search the default way employees find information across Slack and connected apps; and open Slack to outside AI agents through APIs and an MCP server announced in 2025, so other vendors build on Slack rather than around it.
How Slack Technologies, LLC Makes Money
Slack makes money from per-user subscriptions. Teams can start on a free plan with 90 days of message history, then upgrade to Pro (listed at $8.75 per user per month billed monthly, or $7.25 billed annually), Business+, or enterprise plans with central administration, compliance and data controls. Growth is bottom-up: small teams adopt the free product, usage spreads across departments, and IT later buys company-wide licenses. A Fair Billing Policy credits customers for licensed users who go inactive. After a 2025 plan overhaul, Slack stopped selling its separate Slack AI add-on and built AI features such as summaries, AI search and Slackbot into paid plans. Inside Salesforce, Slack is also sold alongside Sales Cloud, Service Cloud and Agentforce, which gives it access to Salesforce's enterprise sales force.
Slack Acquisitions FAQ
What was the landmark $27.7 billion acquisition of Slack by Salesforce in 2021?
On July 21, 2021, Salesforce completed its acquisition of Slack for approximately $27.7 billion in cash and stock, absorbing Slack to serve as the unified conversational layer and digital headquarters across the entire Salesforce ecosystem.
What was the strategic deal with Atlassian for HipChat and Stride in 2018?
In July 2018, Slack formed an alliance with Atlassian, acquiring the intellectual property of rival workplace chat tools HipChat and Stride. Atlassian discontinued both products, migrated its users to Slack, and took an equity stake in Slack.
What was the acquisition of Screenhero in 2015?
In January 2015, Slack acquired screen-sharing and voice-collaboration startup Screenhero for an estimated $20 million, integrating its low-latency voice, video, and co-browsing technology directly into Slack Huddles.
What was the acquisition of Rimeto in 2020?
In July 2020, Slack acquired advanced employee directory startup Rimeto, allowing enterprise users to search colleagues by skills, project history, and reporting hierarchies directly within Slack profiles.
What was the acquisition of Astro Technology in 2018?
In September 2018, Slack acquired Astro, maker of AI-powered email and calendar management applications, bringing talent and machine learning algorithms that improved channel message search and notification triage.
What was the acquisition of Woven in 2021?
In April 2021, Slack acquired smart calendar and scheduling startup Woven, bringing its calendar parsing and scheduling technology into Slack channels and message composition.
What was the acquisition of Missions (by Workato) in 2018?
In late 2018, Slack acquired Missions, a visual workflow automation tool built by robot-makers Workato, which became the technological foundation for the popular Slack Workflow Builder.
What is the Slack Fund and how does it invest?
Launched in 2015 with $80 million backed by venture partners (Accel, Index, KPCB, Social Capital), the Slack Fund invests in early-stage startups building specialized bots, enterprise productivity apps, and developer tools on the Slack platform.
Did Microsoft ever attempt to acquire Slack before building Teams?
In early 2016, senior Microsoft executives (including Qi Lu) considered a bid to acquire Slack for up to $8 billion. However, CEO Satya Nadella and founder Bill Gates pushed to develop an internal competitor, which became Microsoft Teams.
What was the acquisition of Spaces in 2014?
In September 2014, in its earliest acquisition, Slack bought document-collaboration tool Spaces, absorbing its team to build inline document previewing and collaborative rich-text editing inside chat channels.
How did Salesforce integrate Slack with its other major acquisitions?
Salesforce interconnected Slack with MuleSoft (for API integrations), Tableau (for live data analytics alerts in channels), and Agentforce (for deploying AI agents that act on Salesforce CRM data).
What is Slack's current M&A approach under Salesforce?
Today, Slack does not make independent acquisitions; Salesforce executes strategic acquisitions centrally, targeting generative AI tools, conversational search engines, and enterprise data connectivity startups to enhance Slack.
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Compare corporate acquisition records, deal values, and strategic targets
Explore Slack
Core profile pages, founders and related research hubs for this company.