SendPost gives you visibility into what mailbox providers are doing, control over how traffic flows, and an AI layer that spots risk early, before deliverability drops.
SendPost is proud to be recognized as a leader in email deliverability and transactional email software.
SendPost was built by the team of engineers and deliverability experts at SendX, which processes over 300 million emails/month. They've lived inside multi-tenant chaos, warmed IPs at 3 a.m., and debugged inbox drops with zero real signals to work with.
That’s why you’ll find things here you’ve never had before, but need to get full control and visibility into your email deliverability.
"Most MTAs hide the signals that matter. SendPost surfaces them.
LoriBeth Blair
Email Deliverability Consultant
Most MTAs abstract this away. SendPost gives you the full picture so you can actually act on it.
SendPost’s Deliverability AI watches sending patterns and mailbox provider responses in real time, compares them against historical baselines, and flags issues the moment behavior starts to drift.
Stop relying on fixed, one-size-fits-all sending rules. Shape traffic by ISP, adjust queues in real time, and keep risky senders from dragging down your reputation.
You could take a longer lunch break because everything you do manually will be handled automatically by SendPost
You don’t need to overhaul your stack. You add SendPost today, and gain visibility. Route traffic when you’re ready.
A central place to track issues, connect the dots, and stop repeated failures.
What customers are saying...
“I’ve worked with SendGrid, Mailgun, SparkPost — none of them come close to this level of visibility that SendPost offers. It finally gives email deliverability professionals the data we’ve been begging for.”
Email Deliverability Consultant
As monthly volume grew from 100M to 300M+ emails, SendX maintained 95–98% delivery rates and maintained its deliverability team size at only 3 people. All because it moved from legacy sending engines to an AI-driven sending engine — SendPost.
inbox placement even as volume scaled from 100M to 300M emails per month
more sending capacity without adding headcount
saved per week per engineer by removing manual warmups
Issues caught earlier with real-time ISP signals
fewer customer escalations as risky senders surface early
visibility into IPs + domains vs 10–20% most MTAs expose
I've worked with nearly every email API out there, SendGrid, Mailgun, AmazonSES, Sparkpost, SMTP.com, Postmark, Mandrill, and this one takes the cake.
Deliverability Specialist
SendPost gives us the control we lacked with Sendgrid, especially around sending speeds, IPs, and error handling. After two years of use, it’s been consistently reliable with no major downsides.
Free Trial Conversion Specialist, Marketing and Advertising
Everything you need to know about SendPost and transactional email delivery
SendPost is a powerful sending engine, email delivery service, email deliverability platform and cloud MTA built for deliverability specialists, developers and businesses of all sizes. We provide a highly reliable Email API and SMTP Relay service with advanced analytics layer with MTA level controls designed to send your crucial transactional and marketing emails at scale, with a strong focus on ensuring they reach the inbox every time.
Absolutely. SendPost is designed for developers. We offer a robust Email API, SMTP relay service, and SDKs in over 14 programming languages. Additionally, our Email Webhooks allow you to receive real-time event data directly in your application for seamless integration and workflow automation.
No, at the moment we require a demo and up front financial commitment to use SendPost.
SendPost is significantly more cost-effective for transactional and high-volume email at scale. Our pay-as-you-go pricing is tied directly to your usage, not your subscriber count. This means you don't overpay for storing contacts and only get charged for the emails you actually send, making it a more economical and scalable solution for applications.
SendPost provides a powerful dashboard with real-time analytics to track your email performance. You can monitor key metrics like delivery rates, bounces, opens, clicks, and unsubscribes. These detailed insights help you optimize your email program and quickly diagnose any potential deliverability issues.
Still have questions? We're here to help.
Join thousands of developers and businesses who trust SendPost's powerful API and infrastructure to deliver their most important emails.
