Doren Darmon, IT & Operations Editor · Last updated: August 2026 · Facts verified: August 2026
TL;DR verdict: Slack is a channel-based messaging platform, now rebuilt around AI agents and search that reaches across connected apps. It is still the best choice for teams that run on chat, though the free tier permanently deletes anything older than a year and the full AI set only arrives on Business+. Microsoft 365 shops should price Teams first, since chat there comes bundled with software they already pay for.
Ratings: G2: 4.5/5 (38,199 reviews) · TrustRadius: 9.0/10 (10,161 reviews and ratings), verified August 2026
What Is Slack?
Slack is a channel-based messaging platform that organizes work into topic, team, and project channels instead of email threads. Salesforce acquired it in 2021. The product has since moved well past its chat-tool origins. Slackbot now works as a personal AI agent, Workflow Builder builds automations from a written instruction, and enterprise search reaches across connected systems rather than only Slack messages.
Slack reports 200k+ paid customers, 77 of the Fortune 100, and daily active users in more than 150 countries.
What Is Slack Used For?
Teams use Slack as the place where cross-functional work gets coordinated, not just where colleagues chat. The most common patterns:
- Cross-functional project coordination: Per-project channels pull records and updates from tools like Jira, Asana, Google Drive, and Notion so context sits next to the conversation.
- External collaboration: Slack Connect shares channels with clients, vendors, and contractors, reaching up to 250 outside organizations on paid plans.
- Incident response: Dedicated incident channels put responders, logs, and status updates in one thread, and Slack Connect extends that to vendors when an outage crosses company lines.
- Workflow automation: Workflow Builder handles reminders, approvals, onboarding checklists, and request routing through a no-code interface.
- Async check-ins: Clips record short video or audio updates, and huddles cover the quick real-time conversations that do not justify a scheduled call.
- Internal request intake: Structured forms capture requests inside a channel and route each one to the right reviewer automatically.
Key Features of Slack
Two things below matter most if you are weighing Slack against a suite you already own: AI now comes inside the subscription, and Slack Connect still has no real equivalent anywhere else. Everything here was checked against Slack's live product pages in August 2026.
- Channels, DMs, and threads: Channels organize work by team, project, or topic, with full searchable history on paid plans. Threads keep side conversations out of the main feed.
- Huddles: Lightweight audio and video sessions with screen sharing, capped at 50 participants on paid plans, with video limited to 25 people at a time.
- Canvas and lists: A collaborative document format and structured task tracking, both embedded inside channels rather than living in a separate tool.
- AI across the workspace: Conversation and thread summaries, AI search answers, daily recaps, file summaries, huddle notes, translations, and workflow generation from a written prompt. Slackbot acts as a personal AI agent, and third-party agents from Salesforce Agentforce and other vendors run inside Slack alongside it.
- Slack Connect: Shared channels that span organizations, which is the capability competitors have had the hardest time matching.
- App directory: More than 2,600 apps, unlimited on paid plans and capped at 10 on Free.
Slack Pros & Cons
Slack wins on chat experience and app directory size, and loses on a free tier that deletes your data and an AI set locked two tiers up.
What Users Say
Both review platforms put Slack near the top of its category, and both point at the same reason: the integrations. The complaints are just as consistent, and they are about volume rather than capability.
What users consistently praise:
- Integration depth. This is the most frequently named strength on both platforms. Reviewers credit connected apps with keeping work in one place and cutting the number of tools they open in a day.
- Channel-based organization. Per-project channels come up repeatedly as the thing that replaced long email chains and shortened status meetings.
- Ease of use. Adoption is described as fast with little formal training, and adding a person is an invite rather than an admin project.
- Search. Finding a specific file or decision from months earlier is cited as a routine, reliable action rather than an occasional win.
- Real-time messaging. Prompt information sharing is named as a core strength, particularly by distributed and remote-first teams.
What users consistently complain about:
- Free-plan data loss. Only the most recent 90 days stay visible, and anything past a year is destroyed, which rules Slack out for teams that need historical context without a budget.
- Notification volume. Default settings generate more alerts than most people can process, and the activity feed becomes unusable for anyone sitting in many large channels.
- Channel sprawl. As headcount grows, channel count grows faster, and reviewers ask for stronger filtering rather than more places to post.
- Cost at larger team sizes. Reviewers describe cost management as complicated once longer history, administration, and the full AI set enter the picture.
- Desktop resource use. Heavy daily users report the desktop app consuming noticeable memory, with slow channel switching on machines running many other applications.
- Rollout friction. Implementation problems and uneven adoption come up often enough to count as a pattern rather than an outlier.
Where reviewers diverge:
- Adoption difficulty. Buyers and evaluators rate Slack as one of the easiest tools to roll out. Reviewers writing from inside larger deployments describe adoption and channel cleanup as ongoing work with no finish line.
- Notifications and search. Buyers rate both highly as capabilities. Heavy daily users describe notification volume as the single most frustrating part of the product and search in very large workspaces as slower than the marketing suggests.
Slack Pricing
Slack runs four tiers, with AI capability as the main thing that separates them.
Rates come from Slack plans. All pricing information verified August 2026.
Gotchas:
- Monthly billing runs roughly 20% above the annual rate on both paid tiers, $8.75 against $7.25 on Pro and $18 against $15 on Business+.
- New teams that buy Pro or Business+ online within seven days of creating a workspace get 50% off for three months. The offer excludes annual plans and Enterprise+, and standard pricing applies at renewal.
- Free workspaces show only the last 90 days of history. Slack also permanently deletes anything older than one year, under a deletion policy in force since August 2024.
- Free huddles cap at two people with a 30-minute limit, so the free tier does not cover team calls.
- Downgrading to Free disconnects existing Slack Connect channels, deactivates guest accounts, and converts canvases and lists to read-only.
- Enterprise+ is priced by quote only. That means the cost of its compliance controls, including native data loss prevention, is not published anywhere.
Is Slack Worth It?
Yes, if your team runs on chat, connects a lot of apps, and wants AI included in the price rather than sold separately. Pro at $7.25 per user per month is an easy call once you have outgrown the 90-day history limit. Business+ at $15 is where Slack starts to make sense for a company that has to control who can reach what. That tier is where SAML single sign-on and automated user provisioning appear.
Look elsewhere if you already pay for Microsoft 365. Chat comes bundled there with email, Office apps, and storage, and Teams runs the large meetings and webinars that Slack huddles cannot. The same reasoning applies if your company runs on Google Workspace and wants chat sitting next to Gmail, Docs, and Meet without adding a second vendor.
Slack vs Microsoft Teams
The choice is not about feature count. It is about whether you are buying chat on its own or buying it inside a suite you already pay for. Slack is a standalone subscription and wins on messaging experience and app coverage. Teams arrives inside a Microsoft 365 licence you may already hold, which settles the math before either product's features come up.
Where Slack wins: Adding someone is an invite, not an admin configuration job. Channels and threads keep parallel conversations easy to follow, search reliably pulls up old context, and the 2,600-app directory covers more of a typical company's tool set. AI is priced into the plan instead of sold as a separate per-user add-on.
Where Microsoft Teams wins: Large meetings and webinars sit far outside what Slack huddles support, which cap at 50 people with video limited to 25. Teams also has certified conference-room hardware. For anyone already licensed for Microsoft 365, it costs nothing extra to switch on.
Slack Alternatives
Teams leave Slack for two different reasons, and there is a different alternative for each.
- Microsoft Teams: Pick this if you already pay for Microsoft 365 and want chat, large-format meetings, and Office apps under one licence rather than a separate Slack line item.
- Google Chat: Pick this if your company runs on Google Workspace and wants messaging that sits natively next to Gmail, Docs, and Meet. See the Chat evaluation.
How Slack Works With Siit
Slack is a native Siit integration, and it is where employees reach Siit. They raise a request from any channel or DM. That removes the portal step that kills adoption on traditional service desks, and it keeps internal intake where people already work.
From there Siit takes over the handoffs. AI Triage classifies the request, gathers whatever context is missing, and routes it to the right team. Approvals and multi-step processes run as workflow automation, with the request history attached so the next person does not restart the conversation.
Identity actions get executed, not assigned to someone. Through Okta, Siit can reset a password, suspend or reactivate a user, add or remove group membership, and assign an app. All of it runs from the Slack thread where the request started.
Worth knowing what Siit does not do. Its HRIS integrations read employee data into Siit and never write back, so it will not update a record in your HR system. Device actions are limited to locking a device, wiping it, and opening it in the management console, so password resets and encryption-key handling stay outside the device-management path. Across the wider stack Siit reaches 500+ connectable apps, and the named native integrations are where the executable actions live.
