Suggested readings: Transactional Journeys, Dynamic Content in Transactional Journeys, Transactional Email Channel Analytics
Email Channel allows you to send real-time transactional emails to users who enter a journey through an On API Call starter.
Transactional Email is designed for time-sensitive, informational messages such as order confirmations, password resets, account alerts, or appointment notifications. Messages are sent immediately when a user reaches the Email element in the journey.
When you must deliver the messages immediately, content is operational or informational, users expect a message as part of a system action, or delivery speed is critical, you can use Transactional Email. It is not designed for promotional or engagement-driven use cases.
In Transactional Journeys, Email messages are sent as a single, immediate operation.
When a user reaches the Email element:
The message is generated using the design and dynamic content.
The Email is sent immediately.
The journey continues without waiting for user interaction.
Each user receives an individual Email message. Messages are not batched or scheduled.
Transactional Email does not evaluate user consent, opt-in status, or silent hours before sending.
Step 1: Add an Email element on the canvas
To send an Email message in a transactional journey, add an Email element from the channel list on the canvas.
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Step 2: Select sender address
Select the From Email Address to be shown to recipients as the sender and the Reply-To Email Address to receive responses from recipients.
Only pre-configured sender addresses can be used. You can manage your sender addresses in Sender Management.
Step 3: Add subject and preheader
Define the email subject and optional preheader text. You can use dynamic content in both fields.
Fallback values are applied if dynamic values are missing. Dynamic placeholders do not count toward character limits
Enable the Add White Space After Preheader toggle to add white space after the preheader and prevent the email HTML text from appearing in the preheader field.
Step 4: Select dynamic content
Dynamic content allows you to personalize Email messages using data sent with the API request that triggers the journey.
Dynamic content in Email:
Uses only dynamic attributes whitelisted on the On API Call starter.
Does not support CDP attributes, event parameters, coupons, recommendations, or product catalog items.
Can be used in the Subject, Preheader, and Email message.
If a dynamic attribute is not whitelisted on the starter, it cannot be used in the Email content.
Step 5: Design the email
To create your email content, use the Drag and Drop editor or HTML editor, or select a predesigned template.
In the Transactional Email Drag and Drop Editor, the following modules are not supported due to transactional use case requirements:
Unsubscribe modules
Coupon dynamic content
Recommendation Module
In Transactional Email HTML Editor, the following modules are not supported:
Unsubscribe logic or unsubscribe links
Coupon dynamic content
Step 6: Configure tracking parameters
You can enable Tracking Parameters for links in your Email message.
When enabled, UTM parameters are automatically appended to URLs, allowing clicks to be tracked in external analytics tools.
The utm_source, utm_medium, and utm_campaign default parameters are populated automatically. You can optionally define the utm_term and utm_content additional parameters, as well as custom tracking parameters.
UTM parameters are applied only to URLs inside the Email content.
You can add the custom tracking parameters with static values or API-provided dynamic attributes. They support both UTM-prefixed and non-UTM-prefixed labels and are applied to all links in the email, similar to default UTM parameters.
For custom tracking parameters, the label and value cannot exceed 150 characters each.
Step 7: Preview
The Preview section allows you to review how your Email message will appear in the inbox or as a message on a device.
Preview shows the email message and design, dynamic content placeholders, and inbox preview.
Step 8: Preview and test message
Preview and Test Message allows you to render and send test emails without triggering a real journey entry.
You can preview dynamic content values entered manually or click the Use Random Values button for randomly generated values. Dynamic content values used in preview and test messages are for testing purposes only and do not reflect real user data.
This process does not require a real user journey entry, but uses dynamic content values for testing purposes to validate personalization before activating the journey.
You can:
Preview with empty dynamic content.
Preview with randomly generated values.
Preview with manually entered values.
Send test messages immediately.
Send test emails to up to 15 email addresses.
Step 9: Save the Email element
After configuring the Email content and settings, click the Save button to apply the changes. Email elements do not auto-save. Unsaved changes are lost if you leave the page.
Limitations of Transactional Email
The following capabilities are not supported:
Unsubscription modules and links, because transactional use cases bypass opt-in checks and do not include opt-out mechanisms within message content.
Silent hours, as transactional messages are time-critical and must be delivered immediately when triggered.
Send Time Optimization, since delaying delivery conflicts with the real-time nature of transactional communication.
Frequency capping, because transactional messages are informational or operational and are expected to be sent whenever the triggering action occurs.
Coupons, recommendations, or promotional content, due to strict content restrictions that limit transactional messages to purely informational communication.
These constraints ensure fast, deterministic, and reliable message delivery for transactional use cases.