Creating Transactional Templates
This guide explains how to create a new transactional email template in Sender, from configuring settings to designing the layout and connecting it to your API sends.
Where to Find This Feature
In the Sender dashboard, go to: Transactional emails → Templates.
You will see a list of your saved transactional email templates with a search bar and a Sort option. If no templates exist yet, the page displays an empty state. Click New email in the top-right corner to start creating a new template.
Steps to Create a Transactional Template
Step 1 — Configure Template Settings
Click New email on the Templates page. This opens the Create transactional email screen, starting on the Settings stage. You will see a progress bar at the top showing three stages: Settings → Design → API.
Fill in the following fields under Details: enter a Campaign name to identify this template internally, an Email subject line, and optionally an Email Preview text. Then provide a From name and Sender’s email address.
To insert personalization variables into the subject or preview text, click the Custom fields dropdown next to each field and select a variable such as firstname or email.
Under Campaign design, select one of three editor types: Drag and drop builder, Plain text, or Custom HTML. Toggle Enable click tracking on or off based on your needs. Click Save and continue to proceed to the Design stage.
Step 2 — Design the Template Content
On the Design stage, click Edit design to open the email editor. If you selected Drag and drop builder, a visual editor loads with a Building blocks panel on the left. Drag blocks such as Headline, Paragraph, Image, Button, Logo, or Social onto the canvas to build your layout.
To insert a personalization variable in a text block, double-click the text to enter editing mode, then click the Custom fields icon in the inline toolbar. Select a variable like firstname, lastname, or email from the dropdown — it inserts as a merge tag (e.g., {{ firstname }}).
Use the right-side panel to adjust Paragraph settings, Block settings, or Column settings for the selected element.
Click the Preview icon (eye) in the top bar to see desktop and mobile previews of your template. Use Send test email to send a test to your inbox. When you are satisfied, click Save & continue to advance to the API stage.
Step 3 — Retrieve the Template ID for API Use
On the API stage, Sender displays the template’s unique id. Copy this value — you will need it to reference this template when sending transactional emails via the API.
The template ID is a short alphanumeric string (e.g., dN0ol8). Once you have noted the ID, your template is saved and ready to use. You can return to Transactional emails → Templates at any time to find it in your list.
How to Use the Template
To send a transactional email using your template, make a POST request to https://api.sender.net/v2/message/{id}/send, replacing {id} with your template’s ID.
Include a to object in the request body with the recipient’s email and optionally their name. To populate personalization variables in the template, pass a variables object containing key-value pairs that match the custom fields you inserted (e.g., “firstname”: “Jane”).
You can optionally override the template content at send time by including text or html parameters in the request body. Add custom email headers using the headers object if needed.
For SMTP sending, reference the template by including its ID as configured in your SMTP integration settings.
Common Issues
Template not saving when clicking Save and continue → The sender domain has not been verified. Sender requires domain verification before you can save a template. Go to your domain settings and complete the verification process, then return to finish creating the template.
Custom fields not appearing in the editor toolbar → You are not in text editing mode. Double-click a text block to enter inline editing mode, then look for the Custom fields icon in the toolbar that appears above the text area.
Merge tags showing raw syntax in test emails → The variables object was not passed in the API request, or the variable names do not match the custom fields used in the template. Verify that each key in your variables object matches the field name exactly (e.g., firstname, not first_name).
Preview does not match the final email → Some email clients render HTML differently. Use Send test email to verify the output in your actual inbox and check both desktop and mobile previews using the Preview button in the editor.
FAQs
Can I edit a template that is already in use?
Yes. Open the template from the Templates list, make your changes through the Settings or Design stages, and save. Updated content applies to all future sends that reference this template.
How do I add dynamic content to a transactional template?
Use the Custom fields dropdown in the subject line fields during the Settings stage, or click the Custom fields icon in the editor toolbar during the Design stage. When sending via API, pass the corresponding values in the variables object in the request body.
Can I use HTML in my transactional email template?
Yes. Select Custom HTML under Campaign design during the Settings stage to write or paste your own HTML. If you started with the Drag and drop builder, you can also add a Custom HTML block from the Building blocks panel.
What editor types are available for transactional templates?
Sender offers three editor types when creating a transactional template: Drag and drop builder for visual layout editing, Plain text for simple text-only emails, and Custom HTML for full control over the email markup.
Can I override the template content when sending via API?
Yes. Include the text or html parameter in your API request body to override the template’s saved content for that specific send. The original template remains unchanged.