Mattermost vs Rocket.Chat: which to choose for self-hosted team chat
Choose Rocket.Chat when your team is small, up to 50 users, and you want SSO, MFA, LDAP or Active Directory authentication and end-to-end encryption without a license cost, because the free Starter plan includes all of them. This fits when someone on your team can operate MongoDB as a replica set and keep up with upgrades, since Rocket.Chat's standard releases are supported for 6 months and LTS releases for 12 months. Choose Mattermost when you need high availability, air-gapped deployment, PostgreSQL as your standard database, or a paid plan that is already budgeted. Mattermost's HA clustering and FIPS 140-3 compliance sit in the Enterprise tier, and air-gapped deployment sits in Enterprise Advanced, so those requirements are purchases, not defaults.
The decision turns on three questions. First, how many users will be active on day one and in the next year, because the free Starter limit is 50 users and Rocket.Chat's own reference architectures move to multiple instances above 500 concurrent users. Second, whether high availability or air-gapped operation is a hard requirement, since both are paid capabilities on each side and change the architecture: Mattermost HA needs shared file storage such as S3, an S3-compatible service or NAS on every node, and Rocket.Chat recommends a three-member MongoDB replica set. Third, which compliance controls must be present in the tier you buy, such as SAML group mapping, audit trails, or retention. Confirm each of these against the current plan tables with both vendors before you shortlist, because the feature split between free and paid tiers is the most likely place for a surprise.
Which platform fits which team scenario
This table maps common team situations to the platform that fits better and the condition that decides it. Read each row against your own user count, database standards and compliance obligations, and check the paid plan column before assuming a feature is included.
| Scenario | Better fit | Condition that makes it so | Paid plan needed? |
|---|---|---|---|
| Under 50 users, no high availability need | Rocket.Chat | The free Starter plan covers up to 50 users with LDAP or AD, SSO, MFA, end-to-end encryption and retention. Confirm that Starter limits still match your headcount and growth plans. | No for the listed Starter features |
| Regulated team needing HA and SSO | Mattermost | HA requires the Enterprise or Enterprise Advanced plan, and SSO is included from Professional. Mattermost HA also needs shared file storage such as S3, an S3-compatible service or NAS on every node, so confirm your storage design first. | Yes, Professional for SSO and Enterprise for HA |
| Regulated team needing audit trails and failover | Either, depending on the plan you buy | Rocket.Chat lists tamper-evident audit trails and automated failover in its paid plans. Mattermost lists FIPS 140-3 compliance from Enterprise. Ask both vendors to show the specific control evidence your assessor will request. | Yes, for both |
| Air-gapped network | Mattermost | Air-gapped deployment is listed in Enterprise Advanced, and Rocket.Chat lists it as a paid-plan capability that is not available on Starter. Confirm offline licensing, registration and update paths with each vendor for your specific network. | Yes, Enterprise Advanced for Mattermost and a paid Rocket.Chat plan |
| Team already running PostgreSQL | Mattermost | Mattermost uses PostgreSQL as its only database, so it fits existing PostgreSQL standards, backups and skills. Rocket.Chat 8.x requires MongoDB 8.0 or later as a replica set, which adds a second database to operate. | Not applicable |
| Team already running MongoDB | Rocket.Chat | Rocket.Chat fits an existing MongoDB replica set practice, and its three-member replica set is strongly recommended for high availability. Confirm your team can meet its replica set and version requirements. | Not applicable |
| Up to 500 concurrent users on one instance | Either, with a single-instance design | Rocket.Chat's reference architecture suggests one instance with a MongoDB replica set up to 500 concurrent users. Mattermost scales with database and search read replicas. Size both against your own load test results. | Depends on HA and SSO requirements |
| Above 500 concurrent users | Mattermost | Rocket.Chat's multi-instance design above 500 users and its Kubernetes microservices design above 5,000 require a paid plan. Mattermost scales reads through database and search replicas and offers HA in Enterprise, so ask both vendors for a sizing review based on your concurrency. | Yes for Rocket.Chat multi-instance designs |
| Migrating from Slack with an exported workspace | Either, with different import paths | Rocket.Chat imports full Slack workspace exports directly. Mattermost migration from Slack is documented separately, so confirm which export format and mapping your Slack plan supports before choosing. | Not applicable |
How Mattermost and Rocket.Chat are built and what that means for operations
Both platforms are open-core team chat servers that a team runs in its own infrastructure, but they put different parts in the critical path. Mattermost is one Go binary on PostgreSQL, while Rocket.Chat depends on a MongoDB replica set and a bundled Node.js runtime. The cards below cover the components, the file storage and replica set rules, and the scale points where each design asks for a paid plan.
Single binary on PostgreSQL
Mattermost runs as a single Linux binary written in Go and React, with PostgreSQL as its database. For a small or mid-sized team this keeps the moving parts few: one application process, one relational database and the file store. Check that your team already runs PostgreSQL backup, patching and restore procedures, since the database becomes the system you must protect first. Ask Mattermost which PostgreSQL versions your target release supports before you pick a database build.
Redundant nodes for high availability
Mattermost high availability is a paid capability on the Enterprise and Enterprise Advanced plans. It requires redundant application servers, redundant database servers and redundant load balancers, so the single-node layout you start with becomes a multi-node estate. Budget for the extra hosts, the database failover design and the load balancer health checks. Confirm with Mattermost which database topology it validates for your chosen cluster size.
Shared file storage rules for clusters
A Mattermost high availability cluster needs shared file storage on Amazon S3, an S3-compatible service or a NAS mounted on each node. Local file system storage will not work correctly and risks corrupting files, so a cluster built on node-local disks is a failed design, not a cheaper one. Ask who owns the NAS or object store, how it is backed up, and whether its latency and availability match the chat workload. This requirement is the item most often missed when a team plans a cluster from a single-node pilot.
MongoDB replica set as a fixed dependency
Rocket.Chat 8.x requires MongoDB 8.0 or later running as a replica set, even on a single instance. A three-member replica set is strongly recommended for high availability. Your team must maintain replica set membership, elections, oplog sizing and MongoDB upgrades alongside Rocket.Chat upgrades, which is a second database lifecycle to own. Check that your MongoDB operators are comfortable with replica set maintenance before you commit to this stack.
Bundled Node.js and container packaging
Rocket.Chat is a Node.js application, and the official Docker image and Helm chart bundle the Node.js runtime, so you do not install it separately on the host. This simplifies the first deployment but moves runtime patching into the image update cycle. Mattermost ships a compiled Go binary, so its runtime upgrades are a binary replacement. Ask each vendor how it publishes security fixes for its runtime and how quickly you can rebuild or pull a patched image in your own environment.
Reference architectures and the paid multi-instance step
Rocket.Chat's reference architecture suggests one instance with a MongoDB replica set for up to 500 concurrent users, load-balanced instances linked by NATS above 500, and microservices on Kubernetes with the official Helm chart above 5,000. The multi-instance and microservice designs require a paid plan. Mattermost gates its cluster capability to Enterprise and above instead. Model your peak concurrency against these thresholds before you choose a plan, because moving from one instance to several changes both the license and the infrastructure.
Feature by feature: SSO, HA, audit, air-gapped and release support
This table sets Mattermost and Rocket.Chat side by side on the features that usually decide a regulated shortlist, with the plan each one requires. Read each row against the plan you would actually buy, because the free tiers differ sharply on identity, high availability and air-gapped operation. The main takeaway is that Mattermost gates HA and air-gapped deployment behind its paid tiers, while Rocket.Chat's free Starter plan already includes SSO and MFA but not air-gapped deployment.
| Capability | Mattermost | Rocket.Chat |
|---|---|---|
| SSO and AD/LDAP sync | Included from the Professional plan (SAML, OIDC, OAuth, AD/LDAP user sync) | Included on the free Starter plan (LDAP, Active Directory, single sign-on) |
| SAML group mapping | Confirm the group mapping scope for your plan with Mattermost sales and the SAML docs | Listed on paid plans (LDAP and SAML user group mapping) |
| High availability | Enterprise and Enterprise Advanced only, with redundant app servers, database servers and load balancers | Built-in redundancy with automated failover on paid plans; a three-member MongoDB replica set is strongly recommended |
| Shared file storage for HA | Required on each node (Amazon S3, S3-compatible service or NAS); local storage risks file corruption | Confirm storage and failover design for your chosen reference architecture with Rocket.Chat |
| Read replicas | Database read replicas and search replicas supported, with writes sent to the primary | Confirm replica scaling options against the reference architectures for your user count |
| Audit trails | Compliance features depend on plan; confirm which export and audit options your tier includes | Tamper-evident audit trails of messages, files and sessions on paid plans |
| Air-gapped deployment | Enterprise Advanced plan | Paid plans only; not available on Starter |
| FIPS 140-3 compliance | Enterprise plan and above | Not listed in the supplied facts; confirm with Rocket.Chat before assuming support |
| Release cadence and support | Server binaries released monthly on the 16th; ESR v11.7 supported until 2027-05-15 | Standard releases supported 6 months, LTS releases 12 months; end-of-life versions lose security fixes |
What each platform licenses and what is behind a subscription
Mattermost uses three license layers, and each one covers a different part of the product. The compiled server binaries are MIT licensed, the source code used for custom builds is AGPL v3.0 with a commercial alternative from Mattermost, Inc., and the admin tools and configuration files are Apache 2.0. Your legal review should look at which of these artifacts you will actually distribute or modify.
- MIT binaries: The compiled server you download is MIT licensed, so running it internally carries no copyleft obligation.
- AGPL source for custom builds: If you modify the source and build your own server, the AGPL v3.0 terms apply, and a commercial license from Mattermost, Inc. is the alternative.
- Apache 2.0 tools: Admin tools and configuration files fall under Apache 2.0, which is permissive.
- Seat subscriptions: Professional, Enterprise and Enterprise Advanced are prepaid annual subscriptions priced by seat licenses, and the pricing page lists no public prices.
- Feature gates: SSO (SAML, OIDC, OAuth) and AD/LDAP user sync start at Professional, high availability and FIPS 140-3 compliance start at Enterprise, and air-gapped deployment is in Enterprise Advanced.
Confirm with Mattermost which plan includes each control you need, and ask whether a custom build changes the license position for your team.
Mattermost's paid tiers gate features by plan rather than by build, so the plan you buy determines what your deployment can do. Pricing is set through sales contact, which means the seat count, term and included features must be written into the quote. The three tiers map cleanly to identity, resilience and isolation requirements.
- Professional: Includes SSO through SAML, OIDC and OAuth and AD/LDAP user sync, which covers most single-node deployments that need directory integration.
- Enterprise: Adds high availability clustering and FIPS 140-3 compliance, which matter when the service must survive node failure or when cryptographic validation is a procurement requirement.
- Enterprise Advanced: Adds air-gapped deployment, which is the option for networks without internet access.
- Recurring cost: Seat subscriptions renew annually, so the seat count you forecast for year one will shape renewal cost.
- Upgrade path: Ask whether moving between tiers mid-term is prorated and whether the plan you buy now covers the features you expect to need later.
Before signing, ask Mattermost to confirm in writing which plan carries each feature you depend on, and request the seat definition, true-up terms and renewal pricing.
Rocket.Chat's repository is MIT licensed, but the apps/meteor/ee and ee directories sit under a separate Rocket.Chat enterprise license. That split means the core you deploy is permissive while enterprise functionality carries its own terms. Read the LICENSE file and the enterprise license together before you build a plan around any directory or governance feature.
- MIT core: Code outside the enterprise directories is MIT licensed, which keeps the base platform open for internal use and modification.
- Enterprise directories: The apps/meteor/ee and ee directories fall under a separate enterprise license, so code in those paths is governed by different terms.
- Maintainer: Rocket.Chat Technologies Corp. maintains the project, which is the party to ask about license scope.
- Support windows: Standard releases receive support for 6 months and LTS releases for 12 months, so the version you pick sets your upgrade calendar.
- Unsupported versions: Past end of life, a version loses security fixes and may lose connectivity with official mobile and desktop clients.
Ask Rocket.Chat which repository paths your planned features touch, and confirm the license that applies to each one in writing.
Rocket.Chat offers two free tiers with different limits, and the boundary between them affects which teams can run on zero license cost. The Starter plan is capped at 50 users and includes LDAP and Active Directory authentication, single sign-on, multi-factor authentication, end-to-end encryption, retention and read receipts. The free Community workspace allows up to 100 concurrent users with core messaging.
- Starter limit: Up to 50 users, with the identity and security features listed above included.
- Community limit: Up to 100 concurrent users, but the feature set is core messaging rather than the Starter feature list.
- Air-gapped exclusion: Air-gapped deployment is a paid-plan capability and is not available on Starter.
- Multi-instance exclusion: Multi-instance and microservice reference designs require a paid plan.
- Illustrative example: A team of 40 users with directory login and no air-gap requirement could fit Starter, while a team of 80 users that needs replicated instances would need a paid plan.
Confirm the current user counting rules for Starter and Community, because concurrent and total user definitions differ.
Rocket.Chat's paid plans are Commercial, Government and Defense, and they are priced by quote rather than from a published list. The paid tiers add capabilities that matter to regulated teams, including LDAP and SAML user group mapping, tamper-evident audit trails of messages, files and sessions, and built-in redundancy with automated failover. Air-gapped deployment also sits behind these plans.
- Commercial plan: Adds group mapping, audit trails and redundancy features for production teams that exceed Starter.
- Government and Defense plans: Target public sector and defense procurement, and the scope of each should be confirmed against your requirements.
- Audit trails: Tamper-evident logs of messages, files and sessions are a paid-plan feature, so check whether your retention policy needs them.
- Air-gapped operation: Requires a paid plan, so budget for it if the network has no internet access.
- Quoted pricing: Quotes depend on user count, plan and support terms, so ask for a line-item breakdown.
Request a written quote that maps each required control to a named plan, and confirm which features are included in the Government and Defense tiers.
What drives the running cost of each platform
Running either platform costs more than its license or subscription line. The cost depends on how many nodes you run, what shared storage and database members you need, how often you must upgrade to stay supported, and which features sit behind a paid plan. Use the cards below to build the questions you send to each vendor and to your own platform team.
High availability node count
Mattermost high availability needs redundant application servers, redundant database servers and redundant load balancers, and it is available only on Enterprise and Enterprise Advanced. Rocket.Chat reference architectures put a single instance with a MongoDB replica set in place up to 500 concurrent users, while multiple load-balanced instances linked by NATS and microservices on Kubernetes require a paid plan. Count the nodes each design needs at your user target, then price the licenses that unlock them. Ask each vendor which tier covers your node layout.
Shared file storage for clusters
A Mattermost high availability cluster needs shared file storage on Amazon S3, an S3-compatible service or a NAS mounted on each node, because local file system storage will not work correctly and risks corrupting files. This is a recurring infrastructure cost that grows with attachment volume and retention. Confirm who operates the object store or NAS, its backup and its capacity growth, and whether your storage budget is already counted in the platform estimate.
Database replica members
Rocket.Chat 8.x requires MongoDB 8.0 or later running as a replica set, and a three-member replica set is strongly recommended for high availability. Mattermost runs on PostgreSQL, where read replicas and search replicas can be added to scale concurrent users. Compare the number of database members each design needs, the licensing of any managed database service you choose, and the storage and backup footprint of each member.
Operator skills for each database
Your team must run either PostgreSQL with Mattermost or MongoDB with Rocket.Chat, and the skill gap matters more than the software. Check whether your DBAs already manage PostgreSQL replication, failover and backups, or whether MongoDB replica set maintenance is already part of your practice. Ask each vendor which database versions and operational procedures it supports, and budget training or retainer hours for the database that your team does not already run.
Upgrade cadence set by support windows
Mattermost publishes a new server version each month, and its ESR line gives longer support, so the choice of track sets how often you upgrade. Rocket.Chat standard releases are supported for 6 months and LTS releases for 12 months, and unsupported versions can lose connection to the official mobile and desktop clients. Plan a recurring upgrade window, test it in staging, and confirm the staff hours each cycle will take.
Subscription and quoted plan costs
Mattermost sells Professional, Enterprise and Enterprise Advanced as prepaid annual subscriptions by seat licenses, and its pricing page lists no public prices. Rocket.Chat's Starter plan is free up to 50 users, while Commercial, Government and Defense plans are priced by quote. Both are one-time to set up and recurring after that. Request a written quote from each vendor that states seat count, included features, support tier, renewal terms and any price change at renewal.
Moving users and history from one platform to the other
The sequence below separates what Rocket.Chat's importers can carry across from what must be rebuilt by hand, so a move between Mattermost and Rocket.Chat ends with a tested cutover rather than a surprise on the first working day.
Inventory what the source platform holds
Before any export runs, list the users, channels, direct messages, integrations, bots, slash commands, custom emoji, file attachments, retention rules and SSO settings on the source platform. Assign an owner to each item, usually the platform administrator for configuration and a channel owner for content that must be kept. The step is done when the inventory is signed off by the business owner and the compliance lead, because it becomes the scope for the rest of the move and for the written statement of work.
Confirm the importer path for each data type
Rocket.Chat's import tools accept full Slack workspace exports, Slack users from CSV, and a CSV importer for other sources. A Mattermost workspace has to be converted into the CSV format before it can be loaded. Test each path on a copy of the data and record which objects arrive intact, which arrive partially and which do not arrive at all. Ask the Rocket.Chat team or the implementation partner to confirm in writing how history, attachments, threads and user metadata are handled for your exact versions, since the importer behavior is the main technical unknown in this move.
Build and load a test workspace
Stand up a non-production Rocket.Chat instance on MongoDB as a replica set, with the same Rocket.Chat version you plan to run in production. Load a representative sample that includes a large channel, a long thread, a user with a complex group membership and a file attachment. Check that message counts, timestamps, channel membership and user display names match the source. The step is complete when the sample reconciles with the source inventory and every gap is either fixed or accepted by the data owner in writing.
Rebuild identity, SSO and file storage
Imported users do not carry the working sign-in path with them, so configure LDAP or Active Directory, single sign-on and multi-factor authentication in the target before users log in. On the Starter plan, these items are available, but air-gapped deployment and some enterprise directory features require a paid plan, so confirm the entitlement before design. Set up the file storage location and confirm uploads, downloads and retention behavior in the test environment. Done means a test user from each identity group can sign in through the intended path and open an imported file.
Rebuild integrations, bots and retention policies
Integrations, bots and slash commands are not moved as working objects in a chat-to-chat import, so each one has to be recreated, re-authorized and retested against the target. Document the endpoint, the token owner and the expected message format for every integration on the inventory. Recreate retention and read-receipt rules to match your records policy and have the compliance lead verify them against the written policy. Done means every integration has a passing test message and the retention settings are recorded in the change record.
Run a pilot group before the full cutover
Move a small pilot group of users and their channels first, using the same import and rebuild steps as the test run. Ask the pilot users to report missing messages, broken links, notification gaps and client connection issues, including the official mobile and desktop clients. Watch the source and target side by side for a defined period agreed in the project plan. The pilot is complete when the reported issues are closed or documented as known gaps with a workaround, and the business owner signs the go decision.
Cut over users and freeze the source
Schedule a change window, freeze new writes on the source workspace, run the final export and import, and verify counts and access against the inventory. Switch users to the target through the identity path tested earlier, and keep the source read-only for an agreed retention period so that disputed messages can still be checked. The step is done when the reconciliation report is filed, the source is read-only and the help desk has the cutover runbook.
Scope the exit before committing
Moving away from Rocket.Chat or back to Mattermost later repeats most of this sequence in reverse, and the cost is real: data conversion, rebuilt integrations, retraining and a second change window. Ask for a written exit plan in the statement of work that names the export formats, the data owner for each object and the expected effort, and confirm with each vendor which export paths are supported for your version. Done means the exit scope is attached to the contract file before go-live.
Where Mattermost and Rocket.Chat implementations usually run long
The most common slip in a Mattermost project is the file storage decision made after the cluster is built. A Mattermost high availability cluster needs redundant application servers, redundant database servers and redundant load balancers, and every node must mount shared storage on Amazon S3, an S3-compatible service or NAS, because local file system storage will not work correctly and risks corrupting files. Treat shared file storage as a day-one design input, not a later tuning step. Also confirm with Mattermost which plan includes high availability (Enterprise and Enterprise Advanced, per the pricing page), since a Professional subscription will not cover the cluster you are drawing. Read-replica and search-replica sizing belongs in the same design review, with the vendor confirming how reads and writes split across them.
The most common slip in a Rocket.Chat project is operational, not architectural. Rocket.Chat 8.x requires MongoDB 8.0 or later running as a replica set, and a three-member replica set is strongly recommended for high availability, so the database team must own that topology from the start. Upgrade discipline is the second risk: standard releases are supported for 6 months and LTS releases for 12 months, and after end of life the push notification gateway, Marketplace and Omnichannel integrations stop working. Ask Rocket.Chat which line your version falls on and build a recurring upgrade window into the plan. Confirm too that the reference architecture you pick (single instance, load-balanced instances linked by NATS, or Kubernetes with the official Helm chart) is one your license tier allows.
Identity and mobile clients cause rework on both platforms. On Mattermost, SSO over SAML, OIDC or OAuth and AD/LDAP user sync start at the Professional plan, so verify the identity provider configuration against the SAML single sign-on guide before procurement is closed. On Rocket.Chat, LDAP, Active Directory and single sign-on are on the free Starter plan, but LDAP and SAML user group mapping and tamper-evident audit trails are paid-plan items, so an audit requirement that surfaces late can force a plan change mid-project. For mobile, Rocket.Chat warns that unsupported versions may lose connection to the official mobile and desktop clients, so test each client build against your target server version before every upgrade. For air-gapped deployments, Mattermost air-gapped operation sits in Enterprise Advanced, while Rocket.Chat air-gapped deployment is a paid-plan capability with offline registration. Ask both vendors for the certificate, license activation and push notification steps in writing, and confirm how each behaves with no outbound internet access.
Questions buyers ask before choosing between Mattermost and Rocket.Chat
Does the Rocket.Chat Starter plan cover a team under 50 users?
Yes, for user count alone. Rocket.Chat's free Starter plan allows up to 50 users and includes LDAP and Active Directory authentication, single sign-on, multi-factor authentication, end-to-end encryption, retention and read receipts, according to its plans documentation. Two conditions still matter. Air-gapped deployment is a paid-plan capability and is not available on Starter, so an isolated network needs a quote for a different plan. Also confirm with Rocket.Chat that the features you rely on, such as audit depth and group mapping, sit inside Starter, because its paid tiers list LDAP and SAML group mapping and tamper-evident audit trails. Put the exact feature list in writing before you rely on the free tier.
What makes a Mattermost high availability design expensive?
The cost comes from the components HA requires, not from a license alone. Mattermost HA needs redundant application servers, redundant database servers and redundant load balancers, and it is available only on the Enterprise and Enterprise Advanced plans. Each cluster node also needs shared file storage on Amazon S3, an S3-compatible service or NAS, because local file system storage will not work correctly and risks corrupting files. Read replicas and search replicas add more database capacity. Ask the vendor for the Enterprise seat price for your user count, and ask your own team or partner to size the database, storage and load balancer tiers that you will run and maintain.
Does Rocket.Chat require in-house MongoDB expertise to run?
Your team needs working MongoDB operations skills, because Rocket.Chat 8.x requires MongoDB 8.0 or later running as a replica set. A three-member replica set is strongly recommended for high availability. Node.js is bundled in the official Docker image and Helm chart, which reduces the runtime setup, but it does not remove the database work: backups, replica set health, version upgrades and failover tests stay with you. Mattermost instead expects PostgreSQL. If your database team already runs one of these engines well, that skill often decides the question more than the chat product does.
How long does a migration from Slack take, and what drives that effort?
Duration depends on the data you move and how much cleanup you accept, so ask for a timeline in the written scope rather than relying on a general figure. Rocket.Chat's import tools support full Slack workspace exports, Slack users from CSV and a CSV importer for other sources. Mattermost publishes its own Slack migration guide. The main drivers are the size of the message history, the number of channels, direct messages, file attachments and integrations you keep, how users and groups map from your identity provider, and how many rounds of test imports you run before cutover. Ask the vendor or partner to list each of these in the quote so the effort is visible.
Do we need an implementation partner, or can our own team deploy it?
Your own team can deploy either platform if it has the skills for the database, identity integration, storage and upgrades. A partner adds value when the work includes HA design, air-gapped installation, a Slack import with validation, hardening and documented runbooks. DeployOpen plans, implements, integrates, hardens, backs up, upgrades and documents self-hosted platforms inside the client's own infrastructure, and most engagements are fixed-scope with scope, deliverables and timelines agreed in writing before work starts. Ask any partner to show which tasks they own and which remain with your staff after handover.
What does the work need from our own team?
Plan for named owners in four areas: infrastructure, database, identity and the chat administrators who manage users, channels and retention rules. Infrastructure staff own the hosts or Kubernetes cluster, storage and load balancers. Database staff own backups, replication and version upgrades. Identity staff own SSO and group mapping for SAML, OIDC or LDAP. Chat administrators own onboarding and policy. Both products also need a regular upgrade cadence: Rocket.Chat says unsupported versions can lose the ability to connect with official mobile and desktop clients, and Mattermost publishes a new server version each month with ESR releases for longer support. Name these owners before signing, and ask the partner to confirm which parts they will hand over and train on.
Which platform needs fewer paid features for SSO and compliance?
It depends on the feature set you require. Mattermost includes SSO (SAML, OIDC, OAuth) and AD/LDAP user sync from the Professional plan, and FIPS 140-3 compliance and HA from Enterprise. Rocket.Chat's Starter plan includes LDAP, Active Directory, SSO, MFA and end-to-end encryption, while its paid tiers add LDAP and SAML group mapping, tamper-evident audit trails and built-in failover. Before you decide, confirm with each vendor which exact controls and evidence your compliance program requires, and ask for those items in writing. DeployOpen prepares systems, controls and evidence for assessments, but independent auditors issue any attestation or certification.
How DeployOpen helps teams choose and implement a self-hosted chat platform
DeployOpen is a Chainscore Labs company that plans, implements, integrates, hardens, backs up, upgrades and documents self-hosted open-source platforms inside the client's own cloud accounts, data centers or air-gapped networks. For a Mattermost or Rocket.Chat decision, that means the work covers the parts this comparison identifies as the real cost: a PostgreSQL or MongoDB replica set, shared file storage for any Mattermost high availability cluster, SSO and directory sync, retention settings, the upgrade cadence for each release line, and the migration path from Slack. Most engagements are fixed-scope, with scope, deliverables and timelines agreed in writing before work starts, and a quote follows from that written scope. DeployOpen does not publish a price list, so the fastest way to compare cost is to send each platform's requirements and your user count and ask for a quote on each.
DeployOpen does not favor either platform. It is not an official partner, reseller or certified provider of Mattermost, Inc., Rocket.Chat Technologies Corp. or any other vendor unless a supplied fact says so, and it does not receive a commission tied to either choice. A useful first step is a short written assessment that answers the questions this page raises: how many users sit on each plan tier, whether SSO, audit trails or air-gapped operation are required, which database operations your team can support, and which upgrade window your change process allows. The paid feature list is the decision point, so confirm current edition contents directly with each vendor before signing, since subscription terms and feature placement can change.
DeployOpen prepares systems, controls and evidence for compliance assessments, but it does not issue audit reports, attestations or certifications. Independent auditors and certification bodies perform those assessments. If your organization needs evidence for a regulator, ask the assessor which artifacts they expect, such as configuration baselines, access reviews, backup restore tests and upgrade records, and confirm that the chosen platform and plan can produce them. DeployOpen can document and test those controls, and it can run security testing against the deployed chat service, but the result is evidence for your assessor, not a certification of the platform.
