Slackrevenue, acquisition & funding
Team Collaboration SoftwareSan Francisco, CaliforniaFounded 2009
Slack was acquired.
Slack Technologies, Inc. is an American international software company founded in 2009 in Vancouver, British Columbia, Canada.
Slack revenue
Slack's annual revenue was $1.7B in August 2020, its last figure before its buyer bought it.
| As of | Revenue | Source |
|---|---|---|
| Aug 2020 | $1.7B | User Submission |
Who owns Slack
Another company owns Slack. The date and price of the deal are not on record.
Slack funding rounds & investors
Slack has raised $1.4B across nine rounds since 2009. The latest was a $427M Series H in August 2018.
| Date | Round | Raised | Valuation |
|---|---|---|---|
| Aug 2018 | Series H | $427M | $6.7B |
| Sep 2017 | Series G | $412.7M | $4.9B |
| Apr 2016 | Series F | $208M | $3.6B |
| Apr 2015 | Series E | $160M | $2.8B |
| Oct 2014 | Series D | $110.8M | $1B |
| Apr 2014 | Series C | $42.8M | $237.5M |
| Apr 2011 | Series B | $10.7M | $66.7M |
| Mar 2010 | Series A | $5M | $15M |
| 2009 | Seed | $1.5M | – |
| Total raised | $1.4B |
Slack competitors
Slack competes most directly with Discord, Mattermost, RocketChat and element.io. It is the largest of the five by revenue.
| Company | Revenue | Funding | Employees | Customers | Founded |
|---|---|---|---|---|---|
| Slack | $1.7B | $1.4B | 2,730 | 10M | 2009 |
 Discord | $600M | $987.2M | 3,500 | 140M | 2015 |
 Mattermost | $33.1M | $70M | 156 | – | 2016 |
 RocketChat | $31.5M | $26.9M | 176 | 12M | 2015 |
 element.io | $12.5M | – | 114 | – | 2017 |
Slack CEO, founders & employees
Stewart Butterfield founded Slack in 2009 and led it as CEO. Slack had 2,730 employees (August 2020).
- Stewart ButterfieldFounder & CEO
Team mix (Aug 2020): 856 engineers, 447 in sales, 76 in marketing
Slack FAQ
What was Slack's revenue?
Before it was acquired, Slack's annual revenue was $1.7B in August 2020, according to a submission to GetLatka.
How much funding has Slack raised?
Slack raised $1.4B across nine funding rounds before it was acquired. The last was a $427M Series H in August 2018.
How many employees does Slack have?
Slack had 2,730 employees in August 2020.
Who founded Slack?
Stewart Butterfield founded Slack in 2009.
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How this page is sourced
1 from public sources. Founder figures link to the second they were said; public figures name their source; estimates are marked EST. and say whose they are. Not financial advice.
Updated Oct 3, 2026Data disclaimerReport a correctionClaim this profileRun Slack? Join the podcast