Slack

Overview

Slack is a team messaging and collaboration platform built around channels, connected apps and workflows. It is a strong fit for teams coordinating across tools or with outside organizations, but its free plan is a poor choice for anyone who needs a lasting, searchable message archive.

Key features

Channels, apps and external collaboration

Channels give teams shared spaces for conversations, while guest access and Slack Connect extend collaboration beyond the company. Free users can send one-to-one external messages; paid plans support external partners through direct messages, group chats or dedicated channels, with up to 250 organizations. That makes the upgrade more relevant to teams working across company boundaries than to those using Slack only for internal chat.

The app directory spans more than 2,600 apps, including Salesforce, Jira, Google Drive, ChatGPT, Asana, Zoom, GitHub and Notion. Workflow Builder also lets teams automate routine tasks in Slack without coding. Together, these features make Slack useful as a hub for conversations and repeatable processes, though Free users are limited to ten apps; paid plans remove that ceiling.

Calls, AI and security

Free includes one-to-one audio and video meetings with screen sharing. Built-in AI features include summaries, AI search, daily recaps, file summaries, workflow generation and Slackbot. These tools add ways to find and condense work inside Slack, while the free plan’s message-history cap still limits how useful it can be as a long-term reference.

Slack encrypts data at rest and in transit by default. Security controls include two-factor authentication, access logs, SSO, device management and data loss prevention. Free data is deleted after one year; paid subscriptions keep it for life by default, with adjustable settings. Slack supports 12 SSO options, including Okta, Google and Azure, and provides native device management for mobile and desktop.

Pricing

Slack is freemium. Free costs ₹0 and is free forever; it includes 90 days of searchable message history, up to ten apps, one-to-one meetings and one-to-one external messages. That is a useful way to start, but the history limit makes it unsuitable as a durable team archive, and the app cap may constrain tool-heavy teams.

Pro costs $8.75 USD per month when billed monthly. It adds unlimited message history and app integrations, plus group external messages with up to 250 organizations. Business+ costs $18.00 USD per month when billed monthly and includes those same listed collaboration limits, with AI-powered work and advanced AI features. The higher price is most compelling for teams that need those advanced AI capabilities.

Enterprise+ has custom pricing and is aimed at organizations seeking enterprise-grade AI and expanded administration and compliance features; it also includes unlimited history, integrations and group external messaging with up to 250 organizations. Separately, Slack’s published starting price is $7.25 per user per month with annual billing. Teams comparing costs should distinguish that annual-billing starting price from the monthly-billed plan prices above.

Platforms

Slack supports web, Windows, macOS, Linux, iOS and Android, as well as an API. Its broad device coverage suits teams whose members use a mix of desktop and mobile systems.

Who it's for

Slack is best for teams that want channel-based conversations alongside a large app ecosystem, no-code workflow automation and structured collaboration with external organizations. Teams needing long-term message retention or more than ten integrations should budget for a paid plan. Those seeking only a simple internal chat service may not need Slack’s broader collaboration and automation capabilities.

Pros and cons

• Pros: More than 2,600 apps and no-code Workflow Builder give teams ways to connect tools and automate routine work within conversations.
• Pros: Paid plans support external collaboration across up to 250 organizations, useful for work involving multiple partners.
• Pros: Broad platform support and security controls, including encryption, SSO and device management, suit varied device environments.
• Cons: Free search covers only 90 days of messages, limiting its value as a lasting record of decisions.
• Cons: Free allows only ten apps and one-to-one external messaging, so teams with many tools or group partner work may need to pay.

Alternatives

For a dedicated team-chat comparison, browse Team chat apps; for broader workplace coordination, see Team Collaboration Software. Slack’s channel-and-app approach is the stronger fit when those capabilities are the priority.

Business in a Box has a free plan and broader platform support; consider it if core platform access is the priority. Connecteam offers a free plan and trial on web, iOS and Android. Names & Faces offers HR-system sync and employee-directory functions. Workleap Pingboard includes an org chart and people directory, with SSO on its Standard plan. GoProfiles offers a free org chart and directory, employee map and peer recognition. HourSquare has a free plan for teams of up to 10 employees. Organimi offers a free org chart for up to 25 employees and one admin. Openbook offers unlimited rooms and members to start, with room types and templates included on its free plan.

These options are worth considering when a people directory, org chart or stand-up rooms matter more than Slack’s channel conversations and app integrations.

Verdict

Choose Slack if your team needs channel-based work conversations connected to a large app ecosystem, automation and external partners. Its broad platform support and paid collaboration features are compelling; the main reason to look elsewhere is the cost of removing the free plan’s short history and app limits, especially for teams that need only straightforward internal chat.