Emails in Newsletter Studio is all based on a theme. The theme contains

  • Default settings for colors, font size and more.
  • HTML-templates (Razor) for rendering the email and controls.

The default theme that is shipped with the package is based on best practices and provides a solid foundation for the rendering.

You can easily create your own themes to override the default behaviour. Themes only need contain the overrides as we'll fall back on values from the default theme if any setting is not found.

You should never make changes to the default theme as these changes might be overwritten when updating the package.

How to create a Theme

Themes lives inside the "App Plugins" folder, the default theme shipped with Newsletter STudio is located here:


Avoid chaning these files directly as they might be overwritten during upgrades. To customize things create your own theme.

To create a new theme you first need a folder inside App_Plugins, let's use "MySite" as an example and let's call the theme "MyTheme", the folder can be named what ever suites your project. We need to create folders with the following structure:


We will look at each folder in "App_Plugins" and look for a sub folder called "NewsletterStudio". So basically a wildcard search like this:


Inside "MyTheme"-folder we need to create the file "theme.json" to declare our theme. Custom themes only override settings from the default theme so the minimun content of this file would be:

  "name": "My New Theme"

A more useful version would be something like this to override the selectable colors:

  "name": "My New Theme",
  "selectableColors": "#ff00ff,#0000ff,#ffff00",

All other properties would be fetched from the theme.json file in for the default theme App_Plugins/NewsletterStudio/Themes/Default/theme.json

It looks something like this:

  "name": "Default",
  "backgroundColor": "#F3F3F3",

  "selectableColors": "#991BAD,#31D843,#8447FF,#0F2947,#0F2947,#ffffff,#000000",

  "rowBackgroundColor": "#ffffff",

  "controlButtonBackgroundColor": "#31D843",
  "controlButtonTextColor": "#FFFFFF",
  "controlButtonFontFamily": "Arial, 'Helvetica Neue', Helvetica, sans-serif",
  "controlButtonSmallPadding" : "12px 25px",
  "controlButtonSmallFontSize" : "16px",
  "controlButtonMediumPadding" : "16px 35px",
  "controlButtonMediumFontSize" : "18px",
  "controlButtonLargePadding" : "20px 50px",
  "controlButtonLargeFontSize" : "20px",

  "controlTextTextColor": "#000000",
  "controlTextLinkColor": "#8447FF",
  "controlTextFontFamily": "Arial, 'Helvetica Neue', Helvetica, sans-serif",
  "controlTextFontSize": "16px",

  "controlTextHeading1FontFamily": "Arial, 'Helvetica Neue', Helvetica, sans-serif",
  "controlTextHeading1FontSize": "32px",

  "controlTextHeading2FontFamily": "Arial, 'Helvetica Neue', Helvetica, sans-serif",
  "controlTextHeading2FontSize": "28px",

  "controlTextHeading3FontFamily": "Arial, 'Helvetica Neue', Helvetica, sans-serif",
  "controlTextHeading3FontSize": "24px"


Overriding rendering views (cshtml)

There are two ways to override the rendering of the email. If you look into App_Plugins/NewsletterStudio/Themes/Default/Views you should see all views that are invloved in the rendering.

It's possible to override:

  • The main "email.csthml" file which renders the "framework" for the email
  • Individual view for each Email Control.

If you need to override one or more of them just mimic the folder structure inside the global NewsletterStudioExtensions-folder or inside the NewsletterStudioExtensions-folder or inside your custom theme-folder.

Global override

A global override would be used for all themes and basically override the default view. Create a NewsletterStudioExtensions-folder in the App_Plugin-folder and create a view folder inside this:


Inside here, place the cshtml-files that you want to override.

Theme-specific overrides

For a theme-specific override just create the view folder inside your theme, ie:


Inside here, place the cshtml-files that you want to override.

Example 1: Global override for button-view

Create the file: App_Plugins/NewsletterStudioExtensions/Views/Controls/button.cshtml

Update the content to reflect what you need, this file will now be used for all rendering except for when a given theme has a override for this file.

Example 2: Theme-specific override for button-view

Create the file: App_Plugins/MySite/NewsletterStudio/Themes/MyTheme/Views/Controls/button.cshtml

This view will now be used for all email rendering when "My Theme" is used.


  • Fonts (custom fonts?)