whats-best.ai

Business Instant Messaging · head-to-head

Mattermost vs Rocket.Chat

Mattermost

Rest of world

Panel rating

Sovereignty: 1 of 4 dimensions proven

Full evaluation →

Rocket.Chat

Rest of world

Panel rating

Sovereignty: 2 of 4 dimensions proven

Full evaluation →

The written short answer is being updated after a re-evaluation. The scores below are current.

Read this comparison as one judge. Each weighs the same scores by what they care about.

The bench's picks

Same scores, different priorities: each judge's weighting applied to both products. The split is the finding.

Criterion by criterion

Criterion Mattermost Rocket.Chat The bench leans
Channels, threads & search Mattermost, 6 of 6 judges
Encryption & access control Mattermost, 6 of 6 judges
Retention, discovery & co-determination Mattermost, 6 of 6 judges
Deployment & data custody Mattermost, 4 of 6 judges
Integrations & extensibility Mattermost, 5 of 6 judges
European sovereignty split 2–2
Pricing transparency no published price not comparable

Stars show the bench average per criterion; the lean counts which product each judge scored higher. Open a judge's tab for their reasoning on both sides.

Sovereignty, side by side

Dimension Mattermost Rocket.Chat
Legal entity Not determined Not determined
Ownership Not determined Not determined
Data residency Not determined EU optional
Subprocessors US CLOUD Act reach US CLOUD Act reach

Facts, side by side

Only facts both products carry under the same definition — anything else would not be a fair row.

Product · Air gapped definition Air-gapped environment is isolated from the public internet, requiring all necessary components to be available locally.1

captured 1 Oct 2026 · Report an error

yes2

captured 5 Oct 2026 · Report an error

Product · Deployment options on-premises · private cloud · air-gapped3

captured 15 Sep 2026 · Report an error

Self-Hosted · Cloud Hosting4

captured 5 Oct 2026 · Report an error