First, you want to create a new campaign. For this example, we’re going to choose “Regular Ol’ Campaign”.

Next, you’ll be asked to select the list you want to send to. In this case, we’ll select the “MonkeyWrench Newsletter”, and then click “send to segment of list”.

When the drop-down menu appears, select “Email Address” on the left, then “contains” and then the domain that you’d like to send to.

Based on our list and the segmentation parameters we’ve selected, our campaign will go to everyone on the MonkeyWrench Newsletter list who has an aol.com email address. When you click the “refresh count” button, you’ll be able to see how many addresses are in the segment. In this case, the newsletter will go out to about 100 people.

Then, just select “use this segment” and build your campaign as your normally would.

You can use segmentation to combine parameters (like sending to anyone with an aol.com or a gmail.com email address) or to exclude certain domains.

To exclude domains, all you have to do is select “Email Address” from the left column > “does not contain” > aol.com (or whichever domain you are trying to exclude).

When segmented as shown above, the email will not go to anyone with a gmail.com or aol.com email address.

So know that I’ve shown you how to segment, you might be wondering why you would ever use it.

When you go to the Reports page for a given campaign, at the bottom of the page you’ll see “Email Domain Performance”. This list will show you emails, bounces, clicks, opens and unsubscribes based on your recipients’ email domain.

If you notice that emails were sent to gmail.com, but received no opens or clicks (a value of 0%) in addition to few or no bounces, you can conclude that there is an issue with sending to that domain. This will allow you to take corrective action for a problem you may not have otherwise been aware of.

For more detailed information about segmenting your list by domain, as well as some caveats and general food for thought on the subject, be sure to check out Mark Brownlow’s excellent post.

Back in June, when we launched MailChimp v3, we totally rewrote every single line of code and re-structured our database to make the system more scalable and efficient. One side effect of that effort is that we can now  collect and analyze stats across our entire system really easy. We’ve put these stats to good use with our industry comparison metrics, and Chimp Charts. On that note, we’ve posted an interesting new study on list segmentation.

We recently scanned our system for MailChimp users who have used our list segmentation feature. We found 1,988 MailChimp users who sent 10,691 segmented campaigns to 8,762,207 recipients. We compared the email marketing results of those users’ segmented campaigns to the results of their non-segmented campaigns. We actually uncovered some counter-intuitive results in a few places.

Report:  Effects of Segmenting Your Email Marketing Lists