How Sailthru deploys hundreds of millions of personalized emails every day using PowerMTA

How Sailthru deploys hundreds of millions of personalized emails every day using PowerMTA

Ranked #6 in Inc. 500’s Top 100 Advertising and Marketing companies, Sailthru improves customer engagement and retention with today’s leading ecommerce and media brands. Sailthru is an omnichannel marketing technology company with an international client base.



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• Ability to manage large volumes of email traffic

• Capacity to transfer messages from queue to queue under heavy volume

• Legendary stability at a reasonable price point

• Ability to maintain large clusters of servers effortlessly

• Ease of configuration and customized deliverability data


Sailthru deploys hundreds of millions of automated outbound messages daily. Prior to selecting PowerMTA, Sailthru utilized an open source solution, Postfix. While most US-based ESPs and marketing automation technologies experience a digital messaging rush in the morning and early afternoon, Sailthru personalizes delivery time for each individual user based on when they are most likely to open email and convert. This results in high volumes of messages sent around the clock. Therefore, Sailthru demanded industrial-strength messaging infrastructure that would manage its rising email volume and, above all, required stability and dependability in its deliverability platform.


By selecting PowerMTA, Sailthru radically enhanced its messaging performance and dependability, focusing on the ease of configuration and traffic management patterns. PowerMTA impressed Sailthru with its ability to view queues in real-time, and the flexibility to transfer messages from queue to queue under heavy volume, while load times rapidly diminished. Another important feature was the responsiveness of the reporting interface during peak times—it would load immediately and give Sailthru direct views into the responses from the receivers. Additionally, tracking campaigns by JOBID also improved visibility into their client stream.


Sailthru closely analyzed the 2 leading commercial offerings in the space and after thorough review and evaluation, selected Port25’s PowerMTA to be their mission critical email delivery solution. There is much to consider before choosing a commercial grade MTA. But, collectively, Sailthru felt that ease of use, along with performance and legendary stability, a rich feature set, and a reasonable price point made PowerMTA a sound investment for their sending environment.


“PowerMTA has provided Sailthru with a rock solid application that we can push to the limits—and we never have to worry about missing a beat.”

— Director of Global Delivery, Ken Pfeiffer