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Confused by missing emails

Tired of missing or delayed emails?

Save yourself the hassle. Postmark makes it easy to send time-sensitive transactional email to your customers.

Reaching the inbox isn’t enough

Your customers expect application emails to arrive immediately—not eventually.
We don't just claim great deliverability. We share live delivery data so you can judge for yourself.

  • Gmail

  • Apple

  • Hotmail

  • AOL

  • Yahoo

Time to Inbox data updated every 5 minutes

Switch to Postmark and get...

  • Immediate email delivery
  • 45 days of full content history
  • Detailed delivery, open and link tracking
  • Inbound email processing
  • Webhook notifications for open, bounce, and delivery events
  • Responsive email templates

and no more...

  • Upset customers demanding missing or delayed emails
  • Being left in the dark about whether your emails are reaching customers
  • Unexplained outages or delays
  • Complicated infrastructure and APIs

Transactional email for web applications

We provide the pipe to send emails between your web application and your customers. All those newsletters and promotional emails need to go elsewhere.

This means emails from our IP addresses see higher levels of engagement than those who send both transactional and bulk promotional emails together. As a result, our reputation—and by extension your reputation—with providers is better and ensures speedier delivery of your emails.

“Postmark really impressed us with their focus on transactional emails, instead of just broadcasting.”

Cliff Chang

Cliff Chang

Product Engineer at Asana

Asana has been sending with Postmark since 2014.

The industry’s fastest and most reliable delivery

We manually review every new account to help us maintain the industry’s fastest delivery and highest reputation. This usually takes no more than 24 hours (a little longer on weekends) and in the meantime, you can test the entire service by sending to anyone in your company.

“Our experience with the Postmark team has been fantastic. Our emails are sent on time and deliverability is high. We know we can rely on Postmark.”

Claire Schlafly

Claire Schlafly

VP of Operations at Yapmo

Yapmo has been sending with Postmark since 2012.

Everything you need to build applications that rely on email

Since we don’t allow promotional emails, Postmark is able to focus exclusively on building reliable, developer-friendly email infrastructure for web applications.

// Send an email with the Postmark.js library
// Learn more -> https://postmarkapp.com/developer/integration/official-libraries#node-js

// Install with npm
npm install postmark --save

// Require
var postmark = require("postmark");

// Example request
var client = new postmark.Client("server token");

    "From": "sender@example.com",
    "To": "receiver@example.com",
    "Subject": "Test",
    "TextBody": "Hello from Postmark!"

// Require Postmark
var postmark = require("postmark");

// Example request
var client = new postmark.Client("server token");

    "From": "sender@example.com",
    "TemplateId": 120,
    "To": "receiver@example.com",
    "TemplateModel": {
        "Property1" : 1,
        "Property2" : "hello"

  "From": "sender@example.com",
  "To": "451d9b70cf9364d23ff6f9d51d870251569e+ahoy@inbound.postmarkapp.com",
  "Cc": "copied@example.com",
  "Subject": "Test",
  "HtmlBody": "Lorem ipsum",
  "TextBody": "Lorem ipsum",
  "ReplyTo": "reply@example.com",
  "Attachments": [
      "Name": "image.png",
      "Content": "[BASE64-ENCODED CONTENT]",
      "ContentType": "image/png",
      "ContentLength": 4096,
      "ContentID": "myimage.png@01CE7342.75E71F80"

  "FirstOpen": true,
  "Client": {
    "Name": "Chrome 35.0.1916.153",
    "Company": "Google",
    "Family": "Chrome"
  "OS": {
    "Name": "OS X 10.7 Lion",
    "Company": "Apple Computer, Inc.",
    "Family": "OS X 10"
  "Platform": "WebMail",
  "UserAgent": "Mozilla\/5.0 (Macintosh; Intel Mac OS X 10_7_5) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/35.0.1916.153 Safari\/537.36",
  "ReadSeconds": 5,
  "Geo": {
    "CountryISOCode": "RS",
    "Country": "Serbia",
    "RegionISOCode": "VO",
    "Region": "Autonomna Pokrajina Vojvodina",
    "City": "Novi Sad",
    "Zip": "21000",
    "Coords": "45.2517,19.8369",
    "IP": ""
  "MessageID": "883953f4-6105-42a2-a16a-77a8eac79483",
  "ReceivedAt": "2014-06-01T12:00:00",
  "Tag": "welcome-email",
  "Recipient": "john@example.com"

  "ID": 42,
  "Type": "HardBounce",
  "TypeCode": 1,
  "Name": "Hard bounce",
  "Tag": "Test",
  "MessageID": "883953f4-6105-42a2-a16a-77a8eac79483",
  "Description": "The server was unable to deliver your message (ex: unknown user, mailbox not found).",
  "Details": "Test bounce details",
  "Email": "john@example.com",
  "BouncedAt": "2014-08-01T13:28:10.2735393-04:00",
  "DumpAvailable": true,
  "Inactive": true,
  "CanActivate": true,
  "Subject": "Test subject"

Switching to Postmark?

Check out our handy migration guides

Official API libraries for all your favorite languages and frameworks.

“When you step back and look at everything Postmark provides, it has everything you’d want if you were building out your own email infrastructure. Instead of it being one part of our stack we have to fight with and maintain, Postmark takes care of everything for us.”

Joel Flory

Joel Flory


VSCO has been sending with Postmark since 2011.

Built by people who *really* care about email delivery

Postmark is run by Wildbit, a software company founded in 1999 in Philadelphia. We built Postmark while running Beanstalk, and we felt completely blind for emails being sent from our web app.

We’re profitable, debt-free and privately owned. Since 2010 we’ve sent billions of emails for customers, bringing better visibility and inbox rates for transactional email.

  • Ashley Harpp Ashley
  • Dana Chaby Dana
  • Marek Loder Marek
  • Patrick Graham Patrick
  • Chris Nagele Chris
  • Natalie Nagele Natalie
  • Rian Van Der Merwe Rian
  • Artem Chistyakov Artem
  • Andrew Theken Andrew
  • Jake Huggart Jake
  • Mike Elkins Mike
  • Igor Balos Igor
  • Alex Phillip Alex
  • Dave Martin Dave
  • Derek Rushforth Derek
  • Eugene Fedorenko Eugene
  • Matt West Matt
  • Garrett Dimon Garrett
  • Manya Susoev Manya
  • Anna Ward Anna

Still have questions?

Drop a message to one of these fine folks, or call us at 1-855-286-7373.

Send us an email →

  • Ashley Harpp Ashley
  • Dana Chaby Dana
  • Marek Loder Marek
  • Patrick Graham Patrick

Try Postmark today

Start on our free developer plan with 100 emails per month.