Mattermost vs Element: Which Communication Platform Is Right for You?

Architecture: Centralized vs Federated

Mattermost works like Slack: one server, one organization, centralized messaging hub. Teams get out-of-the-box Slack compatibility and deep DevOps integrations.

Element uses the Matrix protocol: federated and decentralized. Your organization runs its own server (homeserver), and can still communicate with other organizations running Matrix. No central authority. No lock-in.

Why this matters: Centralized means speed and simplicity. Federated means sovereignty and interoperability.

Both are self-hosted, so you control your data. Both support managed cloud options (Mattermost Cloud, Element Cloud). And both run better on managed hosting like Opsily—eliminating the ops overhead that makes many teams surrender to SaaS.

What You'll Actually Pay

Mattermost:

• Free (Team Edition): Limited to 10k message history, 40-min calls, no E2EE. Community support only.
• Professional: Starts around €4–6 per user per month (contact sales). Includes automations, DevOps integrations, playbooks.
• Enterprise: Contact sales. Includes FIPS 140-3, legal hold, eDiscovery, 50,000 concurrent users, 24/7 support.
• Deployment: Self-hosted (any infrastructure) or Mattermost Cloud (managed single-tenant).

Element:

• Community (Free): AGPL-licensed, unlimited messaging, E2EE, federation. Good for ~100 users. Community support.
• Enterprise Server Suite Pro: Contact sales. Includes ISO 27001 certified Synapse Pro (next-gen homeserver), installation support, Level 3 SLA support, admin UI, LDAP/SCIM/SSO/OIDC, compliance (CRA, SBOMs).
• Sovereign/Air-Gapped: Enterprise + air-gap deployment. Contact sales.
• Deployment: Self-hosted (Kubernetes, Docker, Helm) or Element Cloud (managed, EU/UK options).

The trade-off: Both require "contact sales" for Enterprise pricing, hiding the real cost. Mattermost Cloud and Element Cloud remove ops overhead but lock you into their infrastructure and pricing tiers. Managed hosting on Opsily gives you Mattermost's power without those constraints.

Encryption, Sovereignty, and Data Control

Mattermost Security:

• E2EE available but optional (varies by plan tier)
• Self-hosted = you control encryption keys and data residency
• FIPS 140-3 and STIG-hardened options for Enterprise (DoD-approved)
• GDPR compliant when self-hosted (you are the data controller)
• No third-party certifications claimed; infrastructure is your responsibility

Element Security:

• E2EE by default. All messages encrypted by default, not an optional upgrade.
• Self-hosted = you control the Matrix homeserver and encryption keys
• ISO/IEC 27001:2022 certified (independently audited)
• Cyber Essentials Plus (UK government certification)
• GDPR compliant; federation eliminates central single-point-of-failure
• Government adoption: French government (Tchap), German military (BwMessenger), NATO communications

When Self-Hosted on Managed Opsily Hosting: Both platforms gain the security benefits of German data centers and professional infrastructure management. Your data stays in the EU. Opsily handles security patches, access controls, and audit logging. You get the sovereignty of self-hosting without the ops burden.

Important clarification: Element's ISO 27001 and Cyber Essentials Plus certs are Element's own certifications for their Synapse server software. Opsily's data centers meet ISO 27001 standards, but Opsily itself does not hold a security certification—you manage the Mattermost/Element instance, and Opsily manages the infrastructure hosting it.