Frequently Asked Questions


The following is a list of frequently asked questions about the MailUp API



Do you charge for use of the MailUp API?

No, there is no charge at this time. You must have a valid MailUp account, however, to send messages through MailUp (except when testing via a MailUp Developer Account or while using a MailUp Free Trial account).

Do I always need a Developer Account?

No, only in some specific cases described on this page.

What is my List's GUID?

It's a unique identifier for your List. The number identifier (e.g. List 4) is unique to your MailUp account, but not within the MailUp system. The GUID, instead, is unique within the entire MailUp system. You can find the GUID for your lists in the "Codes Table" within your MailUp admin console.

Can I use MailUp to send messages from an external application, without logging into the MailUp admin console?

Yes, see the section on sending messages through MailUp from another system (e.g. a Web site or other SaaS application).

I need to integrate my CRM with MailUp. How should I do?

There are many ways to do so.

  • You can use one of the existing plugins (e.g. Salesforce) or an integration "hub" like Zapier
  • You can use the MailUp Rest API and develop a full-featured integration between the two systems
  • You can use MailUp Webhooks to update the CRM in quasi-real-time when something happens on the MailUp side.
  • You can request an automated FTP export and import data into your CRM.

My system requires a type of integration not included in this document. Can it be developed anyway?

Our technicians can analyze and evaluate any custom integration between MailUp and other external systems. We may be able to work with you to add features to MailUp that allow integration with another system. If the requested development can be used by other customers, you may be eligible for a discount on the cost of such development.

Can I install MailUp in my server farm and personalize it?

Unfortunately, this is not possible. Here are the two main reasons:

  1. MailUp's architecture consists of several frontends, backend, SQL, and sending servers, with redundant connections, to ensure the highest level of performance and reliability.
  2. The sending infrastructure is configured so that the sendings are distributed across several IPs, according to constantly changing rules and to the agreements with ISPs, which often also provide guidelines to be followed. We have also signed agreements with many important ISPs, so to allow whitelisting and to prevent messages from being blocked by antispam filters, even with high volumes of emails being sent. MailUp has also agreements in place with ISPs to handle feedback loops. This infrastructure, also connected to a domain and DNS management (e.g. DKIM signatures) is hardly replicable externally, both because of its complexity and because it has to be constantly monitored and updated.

How do I create a subscription form that allows subscriptions to more than one list at the same time?

You can use our HTTP Get/Post API. See Subscribe.aspx.

XMLSubscribe.aspx can be also used, but in this case, a confirmation email will be sent for each selected list. As an alternative, it is possible not to send the email, though we would not suggest this practice.

Is there a way to unsubscribe a user from all lists when he unsubscribes from one of them?

You can do so by using the MailUp Webhooks.