Slack Statistics 2026: Users, Revenue & Slack vs Teams
Slack hasn’t published a user count since 2019. Its last one, more than 12 million daily active users in September 2019, came out before Salesforce bought the company for $27.7 billion, and Slack stopped reporting as a standalone business when the deal closed in July 2021. The 32 million, 38.8 million and 47.2 million daily-user figures on most Slack statistics pages are estimates, and the most-copied version, a table credited to Statista, lists 8.7 million for 2019, below what Slack itself reported that year. Here are the Slack statistics that can be sourced in 2026, company-reported figures first and estimates labeled, each linked inline with its date.
Slack’s key numbers and when each was last reported
| Metric | Figure | As of | Reported by |
|---|---|---|---|
| Daily active users | 12 million+ | September 2019 | Slack |
| Simultaneously connected users | 12.5 million | March 25, 2020 | Slack CEO Stewart Butterfield |
| Organizations with 3+ users | 756,000+ | January 31, 2021 | Slack 10-K |
| Annual revenue | $902.6 million | Fiscal year ended January 31, 2021 | Slack |
| Paid customers (last SEC filing) | 169,000+ | April 30, 2021 | Slack |
| Paid customers (website claim) | 200,000+ | Undated, live October 2026 | Slack About page |
| Fortune 100 companies using Slack | 77 | Undated, live October 2026 | Slack About page |
| Revenue growth since the acquisition | About 2.5x | September 2026 | Salesforce investor presentation |
| Apps in the Slack Marketplace | 2,600+ | October 2026 | Slack website menu |
Slack’s last official user count is 12 million daily users, from 2019
More than 12 million people used Slack every day in September 2019, up about 37% year over year, with more than 6 million paid seats (Slack, 2019). Slack counted a daily active user as anyone who created or consumed content in a 24-hour period, on a free or paid plan.
Slack passed 10 million daily active users in the three months ended January 31, 2019, the figure in its S-1 filing before going public (Slack S-1, 2019).
Simultaneously connected users jumped from 10 million to 12.5 million between March 10 and March 25, 2020, according to Butterfield’s posts on X (CIO Dive, 2020). That is a concurrency count, not daily users, and it tracked the overnight move to remote work covered in remote work statistics.
Slack’s final annual report still said it “regularly review[s]” daily active users but published no number (Slack 10-K, 2021). Salesforce completed the acquisition on July 21, 2021 (Slack 8-K, 2021) and has not reported a Slack user count since.
Treat any post-2020 Slack user count as an estimate. The 2023 to 2025 figures quoted by stats aggregators such as DemandSage (32.3 million, 38.8 million, 47.2 million) come from a table that also puts 2019 at 8.7 million, under the 12 million+ Slack itself reported for September 2019.
Slack users stayed connected nine hours a workday in 2019
Users at paid customers stayed connected to Slack about nine hours per workday and actively used it about 90 minutes, in Slack’s September 2019 data, with more than 5 billion actions a week across the platform (Slack, 2019). That always-open pattern is the background to most context switching statistics.
Slack claims 200,000+ paid customers and 77 of the Fortune 100
Slack lists 200,000+ paid customers, 77 of the Fortune 100, and daily active users in 150+ countries on its About page (Slack, undated, live October 2026). The page carries no date, so read it as Slack’s current claim rather than a dated measurement.
The last count Slack filed with the SEC was 169,000 paid customers on April 30, 2021, with 1,285 paying more than $100,000 a year and 113 paying more than $1 million (Slack Q1 fiscal 2022 results, 2021). Slack counted a paid customer as an organization with three or more users on a paid plan.
The “750,000 companies use Slack” figure dates to January 31, 2021, when Slack reported more than 756,000 organizations with three or more users: more than 600,000 on the free plan and more than 156,000 paying (Slack 10-K, 2021). Slack’s definition of an organization includes schools, government bodies and separate business units of one company, so it was never a count of companies.
More than 65 of the Fortune 100 used Slack as of January 31, 2019 (Slack S-1, 2019), against the 77 on its site today.
Slack’s last reported revenue was $902.6 million; Salesforce says it’s up 2.5x since
Slack’s revenue was $902.6 million in its last full fiscal year as a public company, ended January 31, 2021, up 43% (Slack, 2021).
Its last standalone quarter brought in $273.4 million, up 36%, for the three months ended April 30, 2021 (Slack, 2021).
Salesforce agreed to pay an enterprise value of about $27.7 billion for Slack, announced December 1, 2020 (Salesforce and Slack, 2020).
Slack revenue is up “~2.5x” since the acquisition, according to Salesforce’s Dreamforce investor presentation (Salesforce, September 16, 2026). Salesforce gives no dollar figure or baseline. Applied to Slack’s last full year, 2.5x is about $2.3 billion; applied to its last quarter annualized, about $2.7 billion. That range is our arithmetic, not a reported number.
Salesforce doesn’t report Slack revenue on its own. In fiscal 2026, Slack sat inside a line called “Agentforce 360 Platform, Slack and Other,” which brought in $8.88 billion including $388 million from Informatica (Salesforce 10-K, 2026). From fiscal 2027, Slack moved into “Agentforce Apps,” alongside Sales, Service, Marketing and Commerce, a line worth $7.19 billion in the quarter ended July 31, 2026 (Salesforce 10-Q, 2026).
Slack posted its fastest quarterly growth in net new annual order value since the acquisition in the quarter ended July 31, 2026 (Salesforce, 2026).
Slackbot users grew more than 150% in one quarter of 2026
Slackbot users grew more than 150% quarter over quarter in the three months ended July 31, 2026 (Salesforce, 2026). The rebuilt Slackbot, an AI agent that answers from a person’s messages, files and calendar, became generally available for Business+ and Enterprise+ plans on January 13, 2026 (Salesforce, 2026).
Slack’s MCP server passed 1 million active users within six weeks of launch (Salesforce, 2026). MCP is the standard AI assistants such as Claude and ChatGPT use to read and act in other apps.
Salesforce says Agentforce in Slack saved its own employees more than 500,000 hours in one year (Salesforce, 2026). That is the vendor measuring its own deployment.
Slack’s site advertises more than 2,600 apps in its Marketplace menu (Slack, October 2026). Its About page still says 2,500+, the figure Slack reported for its App Directory in April 2021 (Slack 10-Q, 2021).
Teams last reported 320 million monthly users, in 2023
Microsoft Teams had more than 320 million monthly active users in October 2023 (Microsoft FY24 Q1 earnings call, 2023). That followed 280 million in January 2023 (Microsoft, 2023) and 300 million in April 2023 (Microsoft, 2023).
Microsoft hasn’t given a Teams user number since. By July 2024 it described Teams as essential to “hundreds of millions of people” (Microsoft, 2024), and by our reading of its earnings calls through July 2026, no newer count has been given.
There is no like-for-like Slack vs Teams user comparison after 2019. Most “Teams has X times more users” claims divide Teams’ 2023 monthly users by Slack’s 2019 daily users or by an estimate, which mixes two metrics four years apart. For how the two products differ, see Slack vs Teams.
On September 12, 2025, the European Commission made Microsoft’s Teams commitments legally binding, after an investigation opened in July 2023 following a complaint by Slack (European Commission, 2025). Microsoft must sell Office 365 and Microsoft 365 suites without Teams at a lower price, widen that price gap by 50% on some suites, and keep interoperability and data portability terms for ten years.
Developers use Teams more, but want Slack more
53.1% of developers used Microsoft Teams regularly, against 43.9% for Slack, among 56,109 respondents to Stack Overflow’s 2024 survey (Stack Overflow Developer Survey, 2024). Among professional developers it was 56.2% and 49.1%.
27% of Teams users wanted to use Slack the next year, while fewer than 2% of Slack users wanted Teams (Stack Overflow, 2024).
69.2% of developers using Slack wanted to keep using it, against 48.6% for Teams (Stack Overflow, 2024). The 2025 survey dropped the question, so 2024 is the latest edition. No company-reported or government source publishes a Slack market share; this survey is the closest primary data.
Slack’s Workforce Index: daily AI users report 64% higher productivity
60% of desk workers use AI at work, up from 36% in November 2024, and daily use is 233% higher over the same six months, in Slack’s latest Workforce Index (Slack, 2025). Qualtrics surveyed 5,156 full-time desk workers in Australia, France, Germany, Japan, the U.K. and the U.S. between April 9 and May 1, 2025.
40% of desk workers have used an AI agent, and 23% have had one complete work on their behalf (Slack, 2025).
Daily AI users are 64% more likely to report very good productivity, 58% more likely to report very good focus and 81% more likely to report very good job satisfaction than workers who don’t use AI (Slack, 2025). Which AI tools those workers pick is covered in LLM market share.
Desk workers spend 41% of their time on low-value, repetitive tasks, by an earlier Workforce Index survey of more than 10,000 desk workers (Slack, 2024). More on that in productivity statistics.
More than two hours of meetings a day is the point where most desk workers feel overburdened, and employees who log off at the end of the workday score 20% higher on productivity than those who feel obliged to work after hours (Slack, 2023). See meeting statistics for the wider data.
Keeping email and the calendar in step with Slack
A billion Slack messages a day still leaves customers, candidates and vendors writing in by email, and the meetings that come out of a thread still need a calendar slot. Carly connects to Slack along with thousands of other apps. It can post to a channel or DM you when an important email arrives, turn a Slack request into a task or a calendar hold, and handle the email and scheduling side so Slack isn’t the only place work gets chased. Rules like “post to #sales when a new lead emails” run as workflows. For AI tools that live inside Slack itself, see the best AI assistants for Slack.
FAQ
How many people use Slack in 2026? Slack hasn’t said. Its last published count was more than 12 million daily active users in September 2019 (Slack, 2019). The closest 2026 signals are Salesforce’s own: Slackbot users grew more than 150% quarter over quarter (Salesforce Q2 fiscal 2027 results, 2026), and Slack’s MCP server reached 1 million active users in six weeks (Salesforce Q1 fiscal 2027 results, 2026). Daily-user figures such as 32 million or 47 million are third-party estimates.
How many companies use Slack? Slack’s site claims 200,000+ paid customers and 77 of the Fortune 100 (undated, live October 2026). The last count Slack filed with the SEC was 169,000 paid customers in April 2021. The often-quoted 750,000 is from January 2021 and counts organizations with three or more users, free plans included (Slack, 2021).
What is Slack’s revenue? $902.6 million in its last full standalone fiscal year, ended January 31, 2021 (Slack, 2021). Salesforce doesn’t break Slack out, but its September 2026 investor presentation says Slack revenue is up about 2.5x since the acquisition (Salesforce, 2026), roughly $2.3 billion to $2.7 billion a year by our arithmetic.
Does Microsoft Teams have more users than Slack? Yes, by every published measure. Teams reported more than 320 million monthly active users in October 2023 (Microsoft, 2023), and 53.1% of developers used Teams against 43.9% for Slack (Stack Overflow, 2024). Slack is better liked by the people using it: 69.2% of its developer users want to keep it, against 48.6% for Teams (Stack Overflow, 2024).
What is Slack’s market share? No primary source publishes one. Market share figures online are estimates, or ratios built from Teams’ 2023 monthly users and Slack’s 2019 daily users, two different metrics four years apart.
Related: AI in the Workplace Statistics · Slack alternatives · Slack MCP · Best Slack integrations · How to use Slack
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