# Postmark

> Fast and reliable transactional email delivery service and API for developers, focusing on high inbox deliverability and message streams.

- Website: https://postmarkapp.com/?ref=devshelf.io
- DevShelf page: https://devshelf.io/resource/postmark
- Pricing: Freemium
- Categories: [Email & Notification APIs](https://devshelf.io/category/email-notification-apis.md)
- Last checked: 2026-11-03

## About

Postmark is a fast and reliable email delivery service and API designed for developers to send transactional emails and newsletters. It features separate message streams for transactional and promotional emails to protect deliverability, robust tracking, and dedicated infrastructure without requiring a dedicated IP. Postmark provides official libraries for major programming languages including Node.js, Python, Ruby, PHP, and .NET.

## Alternatives

- [Mailgun](https://devshelf.io/resource/mailgun.md): Transactional email delivery service providing APIs for sending, validating, and optimizing email campaigns. (pricing: Freemium)
- [MailerSend](https://devshelf.io/resource/mailersend.md): Developer-focused transactional email, SMS, and WhatsApp API and SMTP relay service with real-time delivery tracking and webhooks. (pricing: Freemium, Pay-as-you-go)
- [Resend](https://devshelf.io/resource/resend.md): Email platform for developers to send transactional and marketing emails at scale with a focus on deliverability. (pricing: Freemium, Pay-as-you-go)

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