See how Slack's channels, huddles, and workflow tools work, what the Pro and Business+ plans cost, and how Slack compares to Microsoft Teams in 2026.
Slack is a channel-based messaging platform that became the default real-time communication tool for a generation of software and remote-first companies. It was created in 2013 by Stewart Butterfield, Eric Costello, Cal Henderson, and Serguei Mourachov, initially as an internal tool for their gaming company Tiny Speck before being spun out as a standalone product.
Slack launched publicly in February 2014 and grew rapidly by combining searchable, persistent chat channels with deep third-party integrations, replacing much of the day-to-day internal email traffic at many companies. The company went public via a direct listing on the NYSE in 2019.
In December 2020, Salesforce announced it would acquire Slack for roughly $27.7 billion, one of the largest software acquisitions at the time; the deal closed in July 2021 and Slack now operates as part of Salesforce while continuing to be headquartered in San Francisco.
Slack organizes conversation into channels that can be public, private, or shared across organizations, along with direct messages, group messages, and threaded replies to keep discussions organized within busy channels.
Huddles provide lightweight, low-friction audio or video calls launched directly from a channel or DM, positioned as a faster alternative to scheduling a formal video meeting.
Slack supports thousands of app integrations through its App Directory, plus Workflow Builder, a no-code tool for automating routine tasks like intake forms, approvals, and standups.
Since joining Salesforce, Slack has added Slack AI features on paid plans, including AI-generated channel recaps, thread summaries, and search answers that pull from an organization's message history.
Slack's Free plan supports unlimited users with a limited, rolling searchable message history and basic one-to-one voice and video calls, making it usable for very small teams or trial use.
The Pro plan costs $7.25 per user per month billed annually (higher on monthly billing) and unlocks unlimited message history, group calls, and unlimited app integrations.
The Business+ plan costs $15 per user per month billed annually and adds SAML-based single sign-on, compliance exports, and 99.99 percent guaranteed uptime, aimed at larger or more compliance-sensitive organizations.
Enterprise Grid, Slack's top tier, uses custom pricing (commonly cited in the low-to-high $20s per user per month depending on scale and negotiation) and is built for large enterprises that need multiple connected workspaces, org-wide search, and advanced data governance and security controls.
Slack is used for real-time team messaging, file sharing, and workflow automation, organized into topic- or team-based channels rather than a single email-style inbox.
Slack was founded in 2013 by Stewart Butterfield, Eric Costello, Cal Henderson, and Serguei Mourachov, and launched publicly in February 2014.
Slack is owned by Salesforce, which announced its acquisition of Slack in December 2020 for approximately $27.7 billion and closed the deal in July 2021.
Slack has a free plan, a Pro plan at $7.25 per user per month billed annually, a Business+ plan at $15 per user per month billed annually, and custom Enterprise Grid pricing.
A huddle is a lightweight audio or video call that can be started instantly from any channel or direct message without scheduling a formal meeting.
Yes, Slack AI provides channel recaps, thread summaries, and AI-powered search answers on qualifying paid plans.
Slack is generally seen as having a larger third-party integration ecosystem and a more chat-first interface, while Microsoft Teams is more tightly bundled with Microsoft 365 and Office apps.
Yes, the Free plan retains a limited, rolling window of searchable message history; paid plans unlock unlimited history.