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About

How we rank & score
Migration guide · Team Chat

The 3 best Slack alternatives

A hosted team-chat platform, priced per active user, that stores your organization's conversations in Salesforce's cloud.

88
Bottom line

Mattermost is our top pick — Self-hosted team chat built for security-conscious orgs. We compare all 3 options below, with honest trade-offs.

Jump to the full comparison →

The cost

Per-user monthly plans; the free tier hides older message history

Why people consider an alternative

Per-user pricing scales painfully, the free tier caps your searchable history, and your team's entire communication record lives in a vendor's cloud. Self-hosted chat keeps it on infrastructure you run.

The verdict — at a glance

AlternativeLicenseSelf-hostPricingSovereignty
Mattermost★AGPL-3.0YesFree self-host; paid Enterprise88
ZulipApache-2.0YesFree self-host; paid cloud88
Rocket.ChatMITYesFree self-host; paid cloud/enterprise85
88
Macrostack's top pick

Mattermost

Self-hosted team chat built for security-conscious orgs.

Which one fits your situation?

There is no single best answer — it depends on what you are actually trying to do.

Just tell me the best Slack alternative

Mattermost88

Our top pick — the highest Sovereignty Score at 88, and the one we would choose ourselves.

Mattermost vs Zulip →

I have no budget — is there a genuinely free one?

Zulip88

Open source under Apache-2.0. Free self-host; paid cloud

Zulip vs Mattermost →

I want to self-host it and own the data

Rocket.Chat85

Self-hostable, so your data stays on your own server. Free self-host; paid cloud/enterprise

Rocket.Chat vs Mattermost →

Every alternative, compared

#1★ TOP PICK

Mattermost

Self-hosted team chat built for security-conscious orgs.

88
OPEN SOURCEAGPL-3.0SELF-HOSTLOCAL-FIRST 38kupdated 1 mo ago

Mattermost is an open-source, self-hostable Slack alternative with strong security and compliance features, popular with engineering and defense/regulated teams that need to own their data.

Strengths

  • +Purpose-built self-hosted Slack replacement
  • +Strong security/compliance story
  • +Familiar channel UX

Trade-offs

  • −You operate the server
  • −Some features are Enterprise-only
Free self-host; paid Enterprise
WebsiteSourceDocs
#2

Zulip

Threaded team chat that keeps conversations organized.

88
OPEN SOURCEApache-2.0SELF-HOSTLOCAL-FIRST 25kupdated 1 mo ago

Zulip is an Apache-2.0 open-source chat app whose topic-based threading model keeps busy teams' discussions searchable and organized. Self-host it or use the hosted option.

Strengths

  • +Excellent threading model
  • +Permissive Apache-2.0 license
  • +Great for async teams

Trade-offs

  • −Threading is a mental-model shift
  • −Smaller ecosystem than Slack
Free self-host; paid cloud
WebsiteSourceDocs
#3

Rocket.Chat

MIT-licensed, highly customizable team communication.

85
OPEN SOURCEMITSELF-HOSTLOCAL-FIRST 46kupdated 1 mo ago

Rocket.Chat is a permissively licensed (MIT) open-source communications platform you can self-host and reshape freely, with chat, voice, and omnichannel features.

Strengths

  • +Permissive MIT license
  • +Very customizable and extensible
  • +Omnichannel features

Trade-offs

  • −Broad feature set can feel heavy
  • −Some capabilities gated to paid tiers
Free self-host; paid cloud/enterprise
WebsiteSourceDocs

Compare them head-to-head

Mattermost vs Zulip→Mattermost vs Rocket.Chat→Zulip vs Rocket.Chat→

Related comparisons

Alternatives to OpenAI API (ChatGPT)8 optionsAlternatives to Notion4 optionsAlternatives to Datadog4 optionsAlternatives to 1Password4 optionsAlternatives to Google Analytics4 optionsAlternatives to Proprietary Smart-Home Hubs3 options

Entry last verified 2026-07-04. Licenses and pricing change — spotted something out of date? That's a correction we want.

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