📌 Note: A/B Testing availability differs per plan. For more information on plan types please see the add-ons page in your nation.

You are able to perform simple A/B testing for your NationBuilder email campaigns. In this example, you will test which subject line gets the most people to engage with your email.

Note that A/B testing is most valuable for organizations with lists of tens of thousands of people. There are calculators online to determine the ideal sample size and statistical significance of your results. Generally, with smaller lists, you're going to get the best results by understanding who you're reaching out to and simply matching your messaging to them.

If you're doing a split test start by creating a new list. You may also pick an existing list by going to People > Lists. Select a list from the dropdown by hovering over it and clicking Edit.
Once you have selected a list, click on Split. 

1. You may segment the list either by percentages or by equal parts. For A/B testing it is best to split via percentages.

A popular split for subject line testing is dividing your list into percentages of 10%, 10%, and 80%. This allows you to test different subject lines with two small groups of 10%. After observing which test receives the best response you then can send the better subject line to the larger 80%. You can also use this method to test different send times as well as other criteria. 

2. Enter the correct percentage amounts and click Start split to begin the split.

When the split is completed you will see three links to the separate lists next to a count of how many people are in each list. Please note that the people in your original list will be randomly divided only the first time you split the list. Subsequently, every time you split the original list it will split in the same pattern as before.

You can open a list by clicking on the blue names of the newly split lists, or you can locate them at any time under People > Lists.

Once the lists are finished splitting, create a new email. Under Recipients select the List radio button and then use the provided drop down menu to select one of the 10% lists you created. 

After setting up your blast, you will want to clone the email to duplicate the content for your A/B testing.

You can clone emails from two places:

After entering a slug and description for your new mailing, you will automatically be taken to the settings of the new blast you just created. Under Recipients select the second 10% list you created in the split by typing the name of the list into the dropdown menu. Click Save recipients.

Edit the criteria you would like to test under Content. In this case the subject line is being tested.  

Click Save content to save your changes. 

When you are ready, send both of your test emails. Examine the statistics of your emails to determine whether subject line A or B was more effective before moving forward with sending the email to the 80% segment of your list.

How to use lists and batch actions
​How to set up email blasts
​Understanding the results of your email blast
​How to optimize your email deliverability