diff --git a/.bundlewatch.config.json b/.bundlewatch.config.json
index b23d95f343..ed72da161e 100644
--- a/.bundlewatch.config.json
+++ b/.bundlewatch.config.json
@@ -18,7 +18,7 @@
     },
     {
       "path": "./dist/css/ouds-web-utilities.css",
-      "maxSize": "12.75 kB"
+      "maxSize": "13.0 kB"
     },
     {
       "path": "./dist/css/ouds-web-utilities.min.css",
diff --git a/scss/_root.scss b/scss/_root.scss
index 38c36191f6..79fb96f02b 100644
--- a/scss/_root.scss
+++ b/scss/_root.scss
@@ -158,6 +158,7 @@
   --#{$prefix}form-select-indicator: #{$form-select-indicator}; // OUDS mod
   --#{$prefix}form-select-disabled-indicator: #{$form-select-disabled-indicator}; // OUDS mod
   --#{$prefix}form-switch-square-bg: #{$form-switch-square-bg}; // OUDS mod
+  --#{$prefix}form-switch-unchecked-invalid-border-color: #{$form-switch-unchecked-invalid-border-color}; // OUDS mod
 
   // OUDS mod
   // Table-specific styles
@@ -253,6 +254,7 @@
     --#{$prefix}form-select-disabled-indicator: #{$form-select-disabled-indicator-dark}; // OUDS mod
     --#{$prefix}form-color-disabled-filter: #{$form-color-disabled-filter-dark};
     --#{$prefix}form-switch-square-bg: #{$form-switch-square-bg-dark}; // OUDS mod
+    --#{$prefix}form-switch-unchecked-invalid-border-color: #{$form-switch-unchecked-invalid-border-color-dark}; // OUDS mod
 
     // OUDS mod
     // Table-specific styles
diff --git a/scss/_variables-dark.scss b/scss/_variables-dark.scss
index 15c2c32105..8f21cc8762 100644
--- a/scss/_variables-dark.scss
+++ b/scss/_variables-dark.scss
@@ -124,10 +124,11 @@ $form-select-disabled-indicator-dark:   escape-svg(url("data:image/svg+xml,<svg
 // OUDS mod: no $form-switch-bg-image-dark
 
 // scss-docs-start form-validation-colors-dark
-$form-valid-color-dark:                 var(--#{$prefix}success-text-emphasis) !default; // OUDS mod: instead of `$green-300`
-$form-valid-border-color-dark:          var(--#{$prefix}success) !default; // OUDS mod: instead of `$green-300`
-$form-invalid-color-dark:               var(--#{$prefix}danger-text-emphasis) !default; // OUDS mod: instead of `$red-300`
-$form-invalid-border-color-dark:        var(--#{$prefix}danger) !default; // OUDS mod: instead of `$red-300`
+$form-valid-color-dark:                           var(--#{$prefix}success-text-emphasis) !default; // OUDS mod: instead of `$green-300`
+$form-valid-border-color-dark:                    var(--#{$prefix}success) !default; // OUDS mod: instead of `$green-300`
+$form-invalid-color-dark:                         var(--#{$prefix}danger-text-emphasis) !default; // OUDS mod: instead of `$red-300`
+$form-invalid-border-color-dark:                  var(--#{$prefix}danger) !default; // OUDS mod: instead of `$red-300`
+$form-switch-unchecked-invalid-border-color-dark: $form-invalid-border-color-dark !default; // OUDS mod
 // scss-docs-end form-validation-colors-dark
 
 //
diff --git a/scss/_variables.scss b/scss/_variables.scss
index 2079ce3731..3f0d0b79a2 100644
--- a/scss/_variables.scss
+++ b/scss/_variables.scss
@@ -1266,12 +1266,13 @@ $form-switch-checked-bg-size:     add(map-get($spacers, 2), map-get($spacers, 1)
 // stylelint-disable-next-line function-disallowed-list
 $form-switch-checked-bg-position: calc(var(--#{$prefix}border-width) * 3) 50% !default; // OUDS mod
 
-$form-switch-checked-square-bg:     var(--#{$prefix}body-bg) !default; // OUDS mod
-$form-switch-checked-bg:            $supporting-orange !default; // OUDS mod
-$form-switch-checked-border-color:  $supporting-orange !default; // OUDS mod
-$form-switch-checked-filter:        none !default; // OUDS mod
-$form-switch-checked-focus-inner:   var(--#{$prefix}focus-visible-inner-color) !default; // OUDS mod
-$form-switch-checked-focus-outer:   var(--#{$prefix}focus-visible-outer-color) !default; // OUDS mod
+$form-switch-checked-square-bg:                 var(--#{$prefix}body-bg) !default; // OUDS mod
+$form-switch-checked-bg:                        $supporting-orange !default; // OUDS mod
+$form-switch-checked-border-color:              $supporting-orange !default; // OUDS mod
+$form-switch-checked-filter:                    none !default; // OUDS mod
+$form-switch-checked-focus-inner:               var(--#{$prefix}focus-visible-inner-color) !default; // OUDS mod
+$form-switch-checked-focus-outer:               var(--#{$prefix}focus-visible-outer-color) !default; // OUDS mod
+$form-switch-unchecked-invalid-border-color:    #31c3eb !default; // OUDS mod: will be rendered red when mixed with the filter
 // scss-docs-end form-switch-variables
 
 // scss-docs-start input-group-variables
diff --git a/scss/mixins/_forms.scss b/scss/mixins/_forms.scss
index 9521cb8ee6..d63ed307f7 100644
--- a/scss/mixins/_forms.scss
+++ b/scss/mixins/_forms.scss
@@ -154,6 +154,16 @@
         // OUDS mod: label's color doesn't change
       }
     }
+
+    // OUDS mod
+    .form-switch .form-check-input:not(:checked) {
+      @include form-validation-state-selector($state) {
+        filter: $form-switch-filter;
+        border-color: var(--#{$prefix}form-switch-unchecked-invalid-border-color);
+      }
+    }
+    // End mod
+
     .form-check-inline .form-check-input {
       ~ .#{$state}-feedback {
         margin-left: .5em;