Introducing the MailUp API


This document contains all the information you need to connect MailUp to external systems such as Web sites, ecommerce applications, CRM, ERP and CMS systems, and so on. Use of the MailUp API is free of charge, except for data synchronization via Batch FTP. The FTP space used for the integrations is never included in the MailUp service, and is usually provided by the customer.

In a nutshell, the MailUp API allows you to send a message from an external Web site or other application:

Typical Workflow

In a typical workflow, the MailUp database is automatically fed with data from the external system, so that manual imports can be avoided. MailUp then returns important information such as unsubscribed users, invalid email addresses and marketing statistics. In order to understand which solution better suits your needs, let's look at your scenario.

  • Is the database managed inside or outside MailUp? 
  • Is the email message composed inside or outside MailUp?

Here you can find recommended MailUp API methods to execute specific tasks.

For sending transactional emails, you have a choice of using our SMTP relay or transactional messaging APIs.

Plugins, extensions, etc.

Many systems can be integrated with MailUp via our APIs. In some cases, the integration has already been performed and available as a plugin, extension or connector to another application. Learn more about existing MailUp integrations.

Let's Get Started

So, let's get started with the MailUp API: first, let's look at a few terms that are used throughout this documentation.


Peace of Mind

When you integrate your application with MailUp, you have the peace of mind of knowing that MailUp will always ensure that messages are never sent to:

  1. Duplicate email addresses;
  2. Recipients that unsubscribed;
  3. Recipients that reported SPAM (feedback loop management);
  4. Recipients that used the List-Unsubscribe system to unsubscribe;
  5. Recipients that reported a Hard Bounce 550 5.1.1 (invalid address, mailbox not found).