Sprout Forms - Notification Based on Checkbox Value
You're on the right track.

The first thing to note is that the Send Rule field does support shorthand syntax like in your question, however, if you are using compound logic, you will want to use the full object syntax for that logic.

So, instead of (with no reference to object. and single curly braces):

{ checkBoxFieldHandle == 'value' }


You'll want to use the full object syntax to get the expression to evaluate:

{{ object.checkBoxFieldHandle == 'value' }}




The next thing to note is that the checkbox field is a multi-select input, meaning more than one value can be selected. This could be present additional logic challenges for what you are trying to do but assuming you have a checkboxes field with a single checkbox or an opt-in field the logic is more predictable.

Checkboxes are submitted as arrays, so you'll need to make sure you are targeting the correct node in the array. In the case of a single checkbox, we know the first checkbox will be index 0 in the array. Once we have the target checkbox, we can see if it's selected by checking the selected attribute:

{{ object.checkboxFieldHandle.getOptions()[0].selected == true }}


And we can update the same statement to check for false if we want to only send if the checkbox is unchecked:

{{ object.checkboxFieldHandle.getOptions()[0].selected == false }}