Knowledge that stays
Posts, wiki pages and files are organized per space and searchable forever. On Slack's free plan, messages older than 90 days are hidden.
Slack is excellent real-time chat, priced per active user. Communities and organizations that need announcements, documents and knowledge that stay findable, and members who are not paying seats, are better served by HumHub, hosted by CUZY at a flat price.
Slack, owned by Salesforce, is a proprietary team chat with channels, direct messages, huddles and integrations. The free plan shows 90 days of history; paid plans are billed per active user.
Facts about Slack come from the vendor's own pages, checked in September 2026: Slack pricing, Slack help: free plan changes. Prices are those published by the vendor (euros as shown to European visitors, per active user); they may have changed since. Tell us about an error on the contact page and we correct it.
An open-source social network and intranet platform (spaces, streams, wiki, files, calendar, tasks, polls, messaging, member directory, mobile app), extended by the HumHub marketplace and by every CUZY module, hosted by CUZY on dedicated servers in the region you choose, with a flat price and unlimited members.
The questions a buyer, an IT reviewer or a data-protection officer asks both vendors.
| Criterion | Slack | HumHub hosted by CUZY |
|---|---|---|
| Pricing | Pro €6.75 per active user per month billed annually or €8.25 monthly, Business+ €15 or €18, Enterprise+ €45 annually; free plan with 90 days of message history | Team €90/month or €900/year, Business €450/month or €4,500/year, unlimited members, 14-day free trial |
| Fees on payments | Every active member is a paid seat | None. Payments made with the eCommerce module go through your own Stripe account; CUZY takes no commission |
| Single sign-on | Pro: Google sign-in only; SAML single sign-on from Business+ | On every plan, trial included, through OpenID Connect and OAuth modules (Keycloak, Microsoft Entra, Google, LinkedIn, GitHub) and SAML-capable identity providers |
| API | Slack API and apps | HumHub REST API module on every plan |
| Open source | Proprietary | Yes. HumHub under the AGPL, every CUZY module with public source code. 100% of the code can be taken away |
| Data ownership and exit | Workspace export for administrators, depending on the plan | Complete export of the database and files from the dashboard, once a day, on every paid plan; recreate the same platform self-hosted or on HumHub's own hosting |
| Hosting region and isolation | Data residency on Business+ and Enterprise+ | Dedicated servers in the region you choose, Germany (EU), the USA or Singapore (APAC); one isolated stack per community; encrypted backups with a second provider in the same region |
| Extensibility | Slack Marketplace apps and workflows | The whole HumHub marketplace plus every CUZY module on every plan; custom modules and themes on Business after review |
| AI and your content | Slack AI, part of the paid plans, run on the vendor's infrastructure | No AI reads your members' content. CUZY uses AI only for its own operations (anonymized technical logs, support ticket text), as stated in the privacy policy |
Posts, wiki pages and files are organized per space and searchable forever. On Slack's free plan, messages older than 90 days are hidden.
At €15 a user on Business+, 200 members cost €3,000 a month. CUZY Business is €450, Team €90, whatever the number of members.
Mass Notification emails a post to every member of a space; a weekly digest brings back the occasional visitor who never opens a chat app.
Keycloak and OpenID Connect sign-in on every plan; on Slack, SAML starts with Business+.
Germany (EU), the USA or Singapore (APAC), with a processor agreement and a complete export.
Slack is the better fit for a team that works in real-time conversation all day, with many integrations (developer tools, CRM, alerts) posting into channels, and where every member is an active colleague worth a seat. For such teams, an open-source chat such as Mattermost or Rocket.Chat is the closest self-hosted equivalent.
Start a free trial, import members and content with our help, connect your identity provider, and run both platforms side by side until you are ready. Subscribers can export everything from CUZY once a day, so the move is never a one-way door. Tell us about your current setup and we assess what can be carried over.
For organizations and communities that need announcements, spaces, documents, events and a searchable archive, yes. HumHub is not a real-time chat tool; for instant team chat, Slack or an open-source chat such as Mattermost fits better.
A platform priced per organization rather than per user. HumHub hosted by CUZY costs €90/month or €900/year on Team with unlimited members, and registered non-profits can ask for a discount.
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Two weeks with every module and single sign-on, no card asked. Keep everything when you subscribe, export everything if you leave.