Mailmark vs Postmark
Mailmark
mailmark.dev
Postmark
postmarkapp.comSide by side
| Figure | Mailmark | Postmark |
|---|---|---|
| Price from | $10/mo | $5/mo |
| Free plan | — | Yes |
| Free trial | Yes | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | — |
| Plans published | 3 | 8 |
| Spec score · Transactional Email Software | 8.5 (#13) | 8.7 (#7) |
| Spec score · Transactional email services | 8.2 (#22) | 9.2 (#1) |
| Delivery methods | api | Postmark supports REST API, SMTP, and multi-region SMTP routing. |
| Founded | 2024 | 2010 |
| Free plan | Yes | Yes |
| Infrastructure | Mailmark says it runs on AWS across multiple availability zones and uses AWS SES for delivery and S3 for storage. | Postmark says its primary data and servers use Deft and AWS, with redundant API, SMTP, inbound, and web servers; its Deft data center is SOC 2 Type 2 accredited. |
| Monthly send limit | 1000 | 10000 |
| Security | Mailmark says data is encrypted in transit with TLS 1.3 and at rest with AES-256, including email content, attachments, account data, and backups. | Postmark supports TLS and HTTPS, DKIM, SPF, DMARC, two-factor authentication, API permission controls, penetration testing, and DDoS protection. |
| Paid from | 10 | 15 |
| Support | The documentation page says its support team typically responds within 2 hours on business days. | Postmark offers support by email, live chat, and one-on-one calls and reports a 95% customer happiness rating. |
Plans
Postmark
- FreeFree
- Basic$15 a month
- Pro$16.50 a month
- Platform$18 a month
- Custom activity retention$5 a month
- DMARC monitoring$14 a month
- Dedicated IP$50 a month
- High-volume plansPriced on request
In their own words
Postmark
Postmark delivers and tracks application email as an alternative to SMTP or Sendmail. It separates transactional and broadcast messages into different Message Streams and IP infrastructure. Developers can send through REST API, SMTP, or multi-region SMTP routing, with official libraries for Node.js, Python, Rails, Ruby, PHP, and.NET. Inbound messages can be converted to JSON and sent to a webhook URL. Tracking includes delivery, bounces, spam, opens, and links, with event webhooks. Editable responsive templates cover transactional messages such as password resets, receipts, and invitations. The free Developer plan costs nothing, provides 100 emails per month, permits no overages, and does not expire. Basic starts at $15 a month for 10,000 emails per month; extra emails cost $1.80 per 1,000 and are calculated at the end of the billing cycle. Unused emails do not roll over. Postmark lists API and web access. Its iOS app was sunset in June 2025 and is no longer supported.