Best Transactional Email · head-to-head
Mailgun vs Postmark
A sourced, side-by-side comparison for transactional email. Mailgun has the lower entry price. Every figure links to the vendor's own page and the date we captured it.
At a glance
- Price: Mailgun $0/mo vs Postmark $0/mo — Mailgun is cheaper to start.
- Free tier: Mailgun Yes; Postmark Yes.
- HIPAA: Mailgun —; Postmark —.
Side by side
| Mailgun | Postmark | |
|---|---|---|
| Entry price | $0/mo (Free) | $0/mo (Free) |
| Free tier | Yes | Yes |
| HIPAA (BAA) | — | — |
| SOC 2 | Yes | — |
| GDPR | Yes | Yes |
| Best for | Developers needing a mature API with SDKs across 6+ languages | Teams where transactional deliverability is non-negotiable |
Sources — Mailgun: mailgun.com (verified 2026-06-13). Postmark: postmarkapp.com (verified 2026-06-13).
Key features
Mailgun: SOC 2 Type II and ISO/IEC 27001 certified (under Sinch ownership); Real-time email validation API to clean lists before sending; Inbound email parsing and routing (webhooks from received emails); Send-time optimization for per-recipient best delivery timing; SAML SSO on Scale tier and above
Postmark: Message Streams — separate infrastructure for transactional vs. promotional to protect deliverability; Inbound email processing (parse incoming emails into webhooks); MCP server integration for AI coding tools (Claude Code, Cursor, GitHub Copilot); 95%+ customer satisfaction rating; premium support included on all paid tiers; EU data protection and GDPR compliance with DPA available