To create a Custom Field in MailBluster, go to Fields section and then click on Add new.

Enter Field label and then Field merge tag will be auto generated.

Here we used the Field label “State” and Field merge tag “state” is auto generated instantly.

Now we can use this custom field “State” in Leads, Standard Segment, Forms and Campaigns quite easily. Here are some examples:
In Add Lead:

In Standard Segment:

In Forms:

In Subject of Campaigns:

In Edit Content>Compose email under Campaigns:

Using custom fields helps you organize subscriber data beyond basic information like name and email. It also allows you to tailor content based on preferences, locations, or other unique attributes.