Mini Tutorial: How to Segment Email Lists in Listrak

Email campaigns are one of the necessities of having a successful online store. Announcing promotions to your followers is the surest way to create sales, and have repeat customers. Email campaigns, however, can be a danger to your site, if not wielded with caution.

Recently, we experienced an issue where a site was advertising a large sale on their site. This was done by sending an email campaign to a rather large list of email addresses. This turned out to be a mistake, as it resulted in a large amount of customers requesting pages from the site at once, which in turn killed the server. This happens even when caching is on, due to the tracking parameters that campaign managers add to the links in the emails sent.

So instead of the link being:, it becomes

Magento cache doesn’t know not to pay attention to these parameters, so instead it requests a new page for every customer, since the parameter will differ from customer to customer.

One good way to get around this is by creating segments of the list, and then sending the email to a segment every half hour. This will lower the amount of customers attempting to access the site at once. Most, if not all campaign monitors support this functionality, but since we use Listrak here at Demac Media, I’ll explain how to set this up in Listrak.


Lets say we have a list of 100,000 subscribers and we want to send to the safer number of 20,000 every half hour. This means we would need to split the list into 5 segments. This can be done by first going to Contacts > Segmentation > Split Test Segmentation.

On this page there are two fields: “Percentage to Test” and “Number of Segments“. In the first field, we’ll enter “100“, and in the second “5“. This means that 100% of the list is being split into 5 segments.

Now for each message/campaign we want to send, we would need to create it 5 times and schedule them all a half hour apart. Also, each message needs to be associated to a segment. This can be done by clicking, “Edit Filter” then choosing “Split Test Segment” from the dropdown, and then selecting the segment from the next dropdown that appears.

Once you have these messages saved and scheduled, your campaign will be sent to your entire list over a 2.5 hour time frame, saving your server from being bombarded into submission by page requests all at once.