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mailcow vs Postmark

A side-by-side editorial comparison of mailcow and Postmark — release velocity, themes, recent moves, and the top alternatives to consider.

mailcow vs Postmark: at a glance

FeaturemailcowPostmark
SectorCommsComms
Velocity score5.02.5
Sparks · 30d00
Top themesmail-server, self-hosted, security-updates, breaking-changestransactional-email, mcp, api-security, compliance
Last editorial update4d ago4h ago
WebsiteVisit →Visit →

What is mailcow?

mailcow's November release patches an admin RCE and reworks sync jobs.

mailcow ships named monthly releases with lettered revisions, mostly to pull in upstream security fixes for SOGo, Nginx, Redis, Unbound and Rspamd. The November release goes further: it fixes a remote code execution flaw reachable by admins and domain admins, adds mailbox groups, and reworks imapsync so sync jobs reference a separate source. It also caps request bodies at 64 MB, which breaks large SOGo and ActiveSync mail unless NGINX_MAX_BODY_SIZE is raised.

Read the full mailcow trajectory →

What is Postmark?

Postmark adds its own SOC 2 Type 2 report to a run of security work.

Postmark's MCP server has 24 tools and delivery diagnostics, and the team has spent the autumn on account security: webhook verification and monitoring, IP Allowlisting for API sending, and 2FA on the free Developer plan. On November 5 it published its first standalone SOC 2 Type 2 report.

Read the full Postmark trajectory →

mailcow vs Postmark: editorial side-by-side

M
mailcow
COMMS
5.0

mailcow's November release patches an admin RCE and reworks sync jobs.

◆ Current state

mailcow ships named monthly releases with lettered revisions, mostly to pull in upstream security fixes for SOGo, Nginx, Redis, Unbound and Rspamd. The November release goes further: it fixes a remote code execution flaw reachable by admins and domain admins, adds mailbox groups, and reworks imapsync so sync jobs reference a separate source. It also caps request bodies at 64 MB, which breaks large SOGo and ActiveSync mail unless NGINX_MAX_BODY_SIZE is raised.

◆ Where it's heading

The monthly security cadence holds, but recent releases carry more of mailcow's own features and API changes alongside the upstream bumps. Breaking changes now come with explicit migration steps, which suggests the API is being cleaned up for integrators.

◆ Prediction

Expect the promised RCE advisory details next week and a lettered revision within weeks to address fallout from the sync job API and body-size changes.

Postmark logo2.5

Postmark adds its own SOC 2 Type 2 report to a run of security work.

◆ Current state

Postmark's MCP server has 24 tools and delivery diagnostics, and the team has spent the autumn on account security: webhook verification and monitoring, IP Allowlisting for API sending, and 2FA on the free Developer plan. On November 5 it published its first standalone SOC 2 Type 2 report.

◆ Where it's heading

Postmark is pairing agent-facing tooling (Skills, the MCP server) with the compliance and security controls larger buyers ask for. The SOC 2 report removes a procurement blocker rather than adding a feature.

◆ Prediction

Expect more admin and compliance controls, such as audit logs or SSO, alongside further MCP server tools.

Alternatives to mailcow and Postmark

Other Comms products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either mailcow or Postmark.

See all mailcow alternatives → · See all Postmark alternatives →

Recent activity from mailcow and Postmark

Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.

  1. 4d agomailcowMoovember 2026: admin RCE fix, mailbox groups, imapsync rework
  2. 5d agoPostmarkPostmark has its first SOC 2 Type 2 report
  3. 19d agomailcow🎃🐮 Mooctober 2026 | Security Update: PHP 8.2.35, SOGo 5.12.12 & Nginx 1.30.6
  4. 1mo agomailcow2026-09a: Rspamd 4.2.1 and postfix-tlspol bumps
  5. 1mo agoPostmark2FA is now available on the free Developer plan
  6. 1mo agomailcow🍂🐮 Mootember 2026 | Unbound 1.26.1, SOGo 5.12.11 & Redis 7.4.11
  7. 2mo agoPostmarkPostmark Webhooks now verify themselves (and tell you when something's wrong)
  8. 2mo agoPostmarkSecure API sending to trusted IPs with Allowlisting
  9. 2mo agomailcow🏖️🐮 Mooly 2026 | Postfix 3.10.12, Rspamd 4.1.0 & Nginx 1.30.3 - Revision B
  10. 3mo agomailcow🏖️🐮 Mooly 2026 | Postfix 3.10.12, Rspamd 4.1.0 & Nginx 1.30.3 - Revision A
  11. 3mo agoPostmarkPostmark's MCP server: now with 24 tools and delivery diagnostics
  12. 6mo agoPostmarkPython SDK now available

Frequently asked questions

What is the difference between mailcow and Postmark?

They serve adjacent needs but don't currently overlap on shipped themes. mailcow is currently shipping more aggressively (velocity 5.0 vs 2.5), with 0 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.

Is mailcow better than Postmark?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. mailcow is currently shipping more aggressively (velocity 5.0 vs 2.5), with 0 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.

What are the best alternatives to mailcow?

Top mailcow alternatives in Comms are ranked by recent ship velocity. Browse the "mailcow alternatives" section above for the current picks, or visit /alternatives/mailcow for the full list with editorial commentary on each.

What are the best alternatives to Postmark?

Top Postmark alternatives in Comms are ranked by recent ship velocity. Browse the "Postmark alternatives" section above for the current picks, or visit /alternatives/postmark for the full list with editorial commentary on each.