diff --git a/components/o-header/src/scss/_mixins.scss b/components/o-header/src/scss/_mixins.scss
index b29ccf3069..d3f66927f9 100644
--- a/components/o-header/src/scss/_mixins.scss
+++ b/components/o-header/src/scss/_mixins.scss
@@ -129,4 +129,12 @@
 		content: '';
 		margin: -10px; // Undo in-built icon whitespace.
 	}
-}
\ No newline at end of file
+}
+
+@mixin _oHeaderPrimaryLink() {
+	font-weight: 600;
+	text-transform: uppercase;
+	// sass-lint:disable no-vendor-prefixes
+	-webkit-font-smoothing: antialiased;
+	// sass-lint:enable no-vendor-prefixes
+}
diff --git a/components/o-header/src/scss/features/_nav.scss b/components/o-header/src/scss/features/_nav.scss
index 895fa933e2..2ac2038e2e 100644
--- a/components/o-header/src/scss/features/_nav.scss
+++ b/components/o-header/src/scss/features/_nav.scss
@@ -80,10 +80,6 @@
 	}
 
 	.o-header__nav-link--primary {
-		font-weight: 600;
-		text-transform: uppercase;
-		// sass-lint:disable no-vendor-prefixes
-		-webkit-font-smoothing: antialiased;
-		// sass-lint:enable no-vendor-prefixes
+		@include _oHeaderPrimaryLink;
 	}
 }
diff --git a/components/o-header/src/scss/features/_subnav.scss b/components/o-header/src/scss/features/_subnav.scss
index 415e61dee2..fd90d101c8 100644
--- a/components/o-header/src/scss/features/_subnav.scss
+++ b/components/o-header/src/scss/features/_subnav.scss
@@ -5,6 +5,14 @@
 		border-bottom: 1px solid _oHeaderGet('subnav-border');
 	}
 
+	.o-header__subnav--primary {
+		background-color: _oHeaderGet('header-background');
+
+		.o-header__subnav-link {
+			@include _oHeaderPrimaryLink;
+		}
+	}
+
 	.o-header__subnav-wrap-outside {
 		margin-left: -$_o-header-sub-header-focus-margin;
 		margin-right: -$_o-header-sub-header-focus-margin;
@@ -53,21 +61,24 @@
 		// to avoid positioning subnavs relative. This is so absolute children of the subnav are
 		// positioned relative to their closest positioned ancestor `o-header__container`.
 		// An example benefit is o-tooltip support against sub nav items.
-		&+&:not(.o-header__subnav-list--right) .o-header__subnav-item {
+		& + &:not(.o-header__subnav-list--right) .o-header__subnav-item {
 			&:first-child {
 				@include _oHeaderItemSeparatorContent();
-
 			}
 
 			&:first-child:before {
 				top: 50%;
-				margin-top: - $_o-header-subnav-height-base * div($_o-header-item-separator-percentage-height, 2);
-				height: $_o-header-subnav-height-base * $_o-header-item-separator-percentage-height;
+				margin-top: -$_o-header-subnav-height-base *
+					div($_o-header-item-separator-percentage-height, 2);
+				height: $_o-header-subnav-height-base *
+					$_o-header-item-separator-percentage-height;
 
 				@include oGridRespondTo('M') {
 					// stylelint-disable-line max-nesting-depth
-					margin-top: - $_o-header-subnav-height-medium * div($_o-header-item-separator-percentage-height, 2);
-					height: $_o-header-subnav-height-medium * $_o-header-item-separator-percentage-height;
+					margin-top: -$_o-header-subnav-height-medium *
+						div($_o-header-item-separator-percentage-height, 2);
+					height: $_o-header-subnav-height-medium *
+						$_o-header-item-separator-percentage-height;
 				}
 			}
 		}
@@ -86,14 +97,19 @@
 			padding-left: 16px;
 		}
 
-		.o-header__subnav-list--children:not(.o-header__subnav-list--right) &:first-child {
+		.o-header__subnav-list--children:not(.o-header__subnav-list--right)
+			&:first-child {
 			// align left side correctly
 			padding-left: 0;
 		}
 
 		.o-header__subnav-list--breadcrumb & {
 			&:before {
-				@include oIconsContent('arrow-right', _oHeaderGet('link-highlight-text'), $size: $_o-header-icon-size-small);
+				@include oIconsContent(
+					'arrow-right',
+					_oHeaderGet('link-highlight-text'),
+					$size: $_o-header-icon-size-small
+				);
 				content: '';
 				position: relative;
 				top: 0.125em;
@@ -106,12 +122,10 @@
 		}
 	}
 
-
 	.o-header__subnav-list--children.o-header__subnav-list--right {
 		margin-left: auto;
 	}
 
-
 	.o-header__subnav-link {
 		@include _oHeaderLink;
 		@include _oHeaderFancyLink;
@@ -140,7 +154,11 @@
 	}
 
 	.o-header__subnav-button {
-		@include oIconsContent('arrow-left', _oHeaderGet('subnav-button-text'), $size: null);
+		@include oIconsContent(
+			'arrow-left',
+			_oHeaderGet('subnav-button-text'),
+			$size: null
+		);
 		background-color: _oHeaderGet('subnav-button-background');
 		position: absolute;
 		top: 0;
@@ -173,4 +191,4 @@
 		// don't download another icon...
 		transform: rotate(180deg);
 	}
-}
\ No newline at end of file
+}