How do I create and use custom fields?

Custom fields can be used to store additional contact information such as a subscriber's address, city, country, or phone number. They're also great for collecting unique information about subscribers to help you plan more relevant and personalized email content.

Every subscriber list you create has two default fields: name and email address. Any extra fields added to a list are called custom fields. You can add up to 50 custom fields to each list.

Note: Each custom field value has a data limit of 250 characters.

On this page

Creating a new custom field

Navigate to the subscriber list you want to add a custom field to. On the list details page, click Custom fields in the right sidebar. The "Manage custom fields" page will open.

Enter a name for the field and use the Data Type drop-down menu to select what type of field it will be, as shown here:

After you click Add custom field it will appear below, in the list of "Your existing fields". To make any changes, click edit next to the custom field name, as shown here:

Tags in the "Personalization Tag" column can be used in email content and subject lines. See more detail on this below.

The "Preference Center" column is where you can control which fields are visible in the subscriber preference center, if you use one, and which of those are "required" fields.

To delete a custom field, hover your mouse over the field row and click the trash can icon that displays on your right.

Important: Please be aware that deleting a custom field will also delete any data already stored in that field for all of the subscribers on your list.

Viewing and editing custom field data

Now that your custom fields are set up, you can start populating them with data. There are two ways you can do this:

Option 1. Fill in the fields yourself

If you already have the data recorded, you can either import it as a file or enter it manually. Both methods are explained below.

Import the data

You can import a file which includes custom field data, using the Add new subscribers function. See instructions here. If the field values are for email addresses already on your list, the subscriber's profile will simply be updated with the new custom field information.

Tip: If you have existing data for multiple value custom fields, this can also be imported as a file. Check out our guide on how to format your file correctly.

Manual entry

When you are viewing subscriber lists in your account, only the email address and name fields are shown. To see or edit the custom field values for a specific subscriber, click their email address to open the subscriber snapshot:

On the snapshot page, click the Edit <Name> button to add or edit field data, then click Save changes.

Option 2. Allow subscribers to update fields

Any custom fields created for a list can be included on your list's sign up form. The help topics below contain instructions for adding custom fields to forms:

Your custom fields can also be added to the subscriber preference center form, if you use one, for existing subscribers to access and edit when they like.

Smart ways to use custom fields

By using custom fields to capture and store additional information about subscribers you can, over time, build subscriber profiles to help inform the content you send. Custom field data allows you to personalize individual campaigns and specifically target content to suit your reader's preferences and interests:

Personalize email campaigns

Every custom field you create for a list has its own personalization tag that can be used in your campaign content. For example, you could personally greet a subscriber by name, or reference their shipping address, or upcoming birthday. When the campaign is sent the custom field information is merged into the email so every subscriber receives a message personalized for them.

Check out our help topic on personalizing your campaigns to learn more.

Segment your audience

You can also use custom field information to segment subscriber lists, making it easier to send targeted campaign content. For example, you could create a campaign all about small business management and send it only to subscribers who own or manage a small business.

Some other ideas for segments are grouping subscribers who have purchased a house in the last year, or targeting people with a birthday in August. To learn more, see our guide for creating and using segments.