Postmark

Postmark is built by Wildbit, the same team behind the popular project management tool Beanstalk. It focuses exclusively on transactional email: receipts, password resets, notifications, and other automated messages that must be delivered quickly and reliably. Unlike bulk email services, Postmark does not handle marketing campaigns or newsletters. This specialization means it optimizes for deliverability, speed, and tracking. It provides a simple REST API and SMTP relay, with libraries for Ruby, Python, PHP, Node.js, .NET, Java, and more. You can send up to 100 emails per month for free, then pay per email beyond that. Features include real-time bounce and complaint processing, message streams to separate different types of mail, and a webhook system for delivery events. The service also offers a dedicated IP option for high-volume senders. Postmark's dashboard gives you granular analytics on opens, clicks, and delivery status. It integrates with platforms like Shopify, GitHub, and Zendesk. If you run a web app that needs to send critical emails without hassle, Postmark is a solid choice. The company has been around since 2009 and maintains a strong reputation for uptime and support.