diff --git a/packages/eui/changelogs/upcoming/8445.md b/packages/eui/changelogs/upcoming/8445.md
new file mode 100644
index 00000000000..7525bfaf855
--- /dev/null
+++ b/packages/eui/changelogs/upcoming/8445.md
@@ -0,0 +1 @@
+- Updated title, description, and tab sizes in `EuiPageHeader`
\ No newline at end of file
diff --git a/packages/eui/src-docs/src/components/guide_section/_guide_section.scss b/packages/eui/src-docs/src/components/guide_section/_guide_section.scss
index c32e9570840..2f6d429bcaa 100644
--- a/packages/eui/src-docs/src/components/guide_section/_guide_section.scss
+++ b/packages/eui/src-docs/src/components/guide_section/_guide_section.scss
@@ -1,3 +1,7 @@
+.guideSectionTabs__pageHeader h1 {
+  @include euiFontSizeXXL;
+}
+
 .guideSection__tableCodeBlock {
   padding-left: $euiSizeXS;
   padding-right: $euiSizeXS;
diff --git a/packages/eui/src-docs/src/components/guide_tabbed_page/guide_tabbed_page.tsx b/packages/eui/src-docs/src/components/guide_tabbed_page/guide_tabbed_page.tsx
index 78116df1354..65abb1cbad7 100644
--- a/packages/eui/src-docs/src/components/guide_tabbed_page/guide_tabbed_page.tsx
+++ b/packages/eui/src-docs/src/components/guide_tabbed_page/guide_tabbed_page.tsx
@@ -209,6 +209,7 @@ export const GuideTabbedPage: FunctionComponent<GuideTabbedPageProps> = ({
     <>
       {renderNotice()}
       <EuiPageHeader
+        className="guideSectionTabs__pageHeader"
         restrictWidth
         paddingSize="l"
         pageTitle={
diff --git a/packages/eui/src/components/page/page_header/__snapshots__/page_header.test.tsx.snap b/packages/eui/src/components/page/page_header/__snapshots__/page_header.test.tsx.snap
index 9718252d55a..e8954d5ed79 100644
--- a/packages/eui/src/components/page/page_header/__snapshots__/page_header.test.tsx.snap
+++ b/packages/eui/src/components/page/page_header/__snapshots__/page_header.test.tsx.snap
@@ -32,13 +32,13 @@ exports[`EuiPageHeader props alignItems bottom is rendered 1`] = `
         class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
       >
         <h1
-          class="euiTitle emotion-euiTitle-l"
+          class="euiTitle emotion-euiTitle-m"
         >
           Page title
         </h1>
       </div>
       <div
-        class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+        class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
       >
         <div
           class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -74,13 +74,13 @@ exports[`EuiPageHeader props alignItems center is rendered 1`] = `
         class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
       >
         <h1
-          class="euiTitle emotion-euiTitle-l"
+          class="euiTitle emotion-euiTitle-m"
         >
           Page title
         </h1>
       </div>
       <div
-        class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+        class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
       >
         <div
           class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -116,13 +116,13 @@ exports[`EuiPageHeader props alignItems stretch is rendered 1`] = `
         class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
       >
         <h1
-          class="euiTitle emotion-euiTitle-l"
+          class="euiTitle emotion-euiTitle-m"
         >
           Page title
         </h1>
       </div>
       <div
-        class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+        class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
       >
         <div
           class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -158,13 +158,13 @@ exports[`EuiPageHeader props alignItems top is rendered 1`] = `
         class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
       >
         <h1
-          class="euiTitle emotion-euiTitle-l"
+          class="euiTitle emotion-euiTitle-m"
         >
           Page title
         </h1>
       </div>
       <div
-        class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+        class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
       >
         <div
           class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -276,7 +276,7 @@ exports[`EuiPageHeader props page content props are passed down is rendered 1`]
       >
         <h1
           aria-label="aria-label"
-          class="euiTitle testClass1 testClass2 emotion-euiTitle-l-euiTestCss"
+          class="euiTitle testClass1 testClass2 emotion-euiTitle-m-euiTestCss"
           data-test-subj="test subject string"
         >
           <span
@@ -292,7 +292,7 @@ exports[`EuiPageHeader props page content props are passed down is rendered 1`]
           class="euiSpacer euiSpacer--l emotion-euiSpacer-l"
         />
         <div
-          class="euiText emotion-euiText-constrainedWidth-m"
+          class="euiText emotion-euiText-constrainedWidth-s"
         >
           <p>
             Description
@@ -307,7 +307,7 @@ exports[`EuiPageHeader props page content props are passed down is rendered 1`]
       </div>
       <div
         aria-label="aria-label"
-        class="euiFlexGroup testClass1 testClass2 emotion-euiFlexGroup-responsive-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems-euiTestCss"
+        class="euiFlexGroup testClass1 testClass2 emotion-euiFlexGroup-responsive-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems-euiTestCss"
         data-test-subj="test subject string"
       >
         <div
@@ -334,7 +334,7 @@ exports[`EuiPageHeader props page content props are passed down is rendered 1`]
       />
       <div
         aria-label="aria-label"
-        class="euiTabs testClass1 testClass2 emotion-euiTabs-l-euiTestCss"
+        class="euiTabs testClass1 testClass2 emotion-euiTabs-m-euiTestCss"
         data-test-subj="test subject string"
         role="tablist"
       >
@@ -346,7 +346,7 @@ exports[`EuiPageHeader props page content props are passed down is rendered 1`]
           type="button"
         >
           <span
-            class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
+            class="euiTab__content eui-textTruncate emotion-euiTab__content-m"
           >
             Tab 1
           </span>
@@ -359,7 +359,7 @@ exports[`EuiPageHeader props page content props are passed down is rendered 1`]
           type="button"
         >
           <span
-            class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
+            class="euiTab__content eui-textTruncate emotion-euiTab__content-m"
           >
             Tab 2
           </span>
diff --git a/packages/eui/src/components/page/page_header/__snapshots__/page_header_content.test.tsx.snap b/packages/eui/src/components/page/page_header/__snapshots__/page_header_content.test.tsx.snap
index dd1822a4b07..c7c4b872ef0 100644
--- a/packages/eui/src/components/page/page_header/__snapshots__/page_header_content.test.tsx.snap
+++ b/packages/eui/src/components/page/page_header/__snapshots__/page_header_content.test.tsx.snap
@@ -27,13 +27,13 @@ exports[`EuiPageHeaderContent props alignItems bottom is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         Page title
       </h1>
     </div>
     <div
-      class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+      class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
     >
       <div
         class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -65,13 +65,13 @@ exports[`EuiPageHeaderContent props alignItems center is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         Page title
       </h1>
     </div>
     <div
-      class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+      class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
     >
       <div
         class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -103,13 +103,13 @@ exports[`EuiPageHeaderContent props alignItems stretch is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         Page title
       </h1>
     </div>
     <div
-      class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+      class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
     >
       <div
         class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -141,13 +141,13 @@ exports[`EuiPageHeaderContent props alignItems top is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         Page title
       </h1>
     </div>
     <div
-      class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+      class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
     >
       <div
         class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -258,7 +258,7 @@ exports[`EuiPageHeaderContent props children is rendered even if content props a
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         Page title
       </h1>
@@ -268,7 +268,7 @@ exports[`EuiPageHeaderContent props children is rendered even if content props a
       Child
     </div>
     <div
-      class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+      class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
     >
       <div
         class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -293,7 +293,7 @@ exports[`EuiPageHeaderContent props children is rendered even if content props a
       class="euiSpacer euiSpacer--l emotion-euiSpacer-l"
     />
     <div
-      class="euiTabs emotion-euiTabs-l"
+      class="euiTabs emotion-euiTabs-m"
       role="tablist"
     >
       <button
@@ -304,7 +304,7 @@ exports[`EuiPageHeaderContent props children is rendered even if content props a
         type="button"
       >
         <span
-          class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
+          class="euiTab__content eui-textTruncate emotion-euiTab__content-m"
         >
           Tab 1
         </span>
@@ -317,7 +317,7 @@ exports[`EuiPageHeaderContent props children is rendered even if content props a
         type="button"
       >
         <span
-          class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
+          class="euiTab__content eui-textTruncate emotion-euiTab__content-m"
         >
           Tab 2
         </span>
@@ -338,7 +338,7 @@ exports[`EuiPageHeaderContent props description is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <div
-        class="euiText emotion-euiText-constrainedWidth-m"
+        class="euiText emotion-euiText-constrainedWidth-s"
       >
         <p>
           Description
@@ -360,7 +360,7 @@ exports[`EuiPageHeaderContent props pageTitle is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         Page title
       </h1>
@@ -380,7 +380,7 @@ exports[`EuiPageHeaderContent props pageTitle is rendered with icon 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         <span
           class="emotion-euiPageHeaderContent__titleIcon"
@@ -404,7 +404,7 @@ exports[`EuiPageHeaderContent props pageTitle is rendered with icon and iconProp
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     >
       <h1
-        class="euiTitle emotion-euiTitle-l"
+        class="euiTitle emotion-euiTitle-m"
       >
         <span
           class="testClass1 testClass2 emotion-euiPageHeaderContent__titleIcon-euiTestCss"
@@ -432,7 +432,7 @@ exports[`EuiPageHeaderContent props pageTitle is rendered with pageTitleProps 1`
     >
       <h1
         aria-label="aria-label"
-        class="euiTitle testClass1 testClass2 emotion-euiTitle-l-euiTestCss"
+        class="euiTitle testClass1 testClass2 emotion-euiTitle-m-euiTestCss"
         data-test-subj="test subject string"
       >
         Page title
@@ -481,7 +481,7 @@ exports[`EuiPageHeaderContent props rightSideItems is rendered 1`] = `
       class="euiFlexItem emotion-euiFlexItem-grow-2-euiPageHeaderContent__leftSideItems"
     />
     <div
-      class="euiFlexGroup emotion-euiFlexGroup-wrap-l-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
+      class="euiFlexGroup emotion-euiFlexGroup-wrap-m-flexStart-stretch-row-euiPageHeaderContent__rightSideItems"
     >
       <div
         class="euiFlexItem emotion-euiFlexItem-growZero-euiPageHeaderContent__rightSideItem"
@@ -514,7 +514,7 @@ exports[`EuiPageHeaderContent props rightSideItems is rendered with rightSideGro
     />
     <div
       aria-label="aria-label"
-      class="euiFlexGroup testClass1 testClass2 emotion-euiFlexGroup-wrap-l-flexStart-stretch-column-euiPageHeaderContent__rightSideItems-euiTestCss"
+      class="euiFlexGroup testClass1 testClass2 emotion-euiFlexGroup-wrap-m-flexStart-stretch-column-euiPageHeaderContent__rightSideItems-euiTestCss"
       data-test-subj="test subject string"
     >
       <div
@@ -552,7 +552,7 @@ exports[`EuiPageHeaderContent props tabs is rendered 1`] = `
         Tab 1
       </h1>
       <div
-        class="euiTabs emotion-euiTabs-xl"
+        class="euiTabs emotion-euiTabs-l"
         role="tablist"
       >
         <button
@@ -563,7 +563,7 @@ exports[`EuiPageHeaderContent props tabs is rendered 1`] = `
           type="button"
         >
           <span
-            class="euiTab__content eui-textTruncate emotion-euiTab__content-xl"
+            class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
           >
             Tab 1
           </span>
@@ -576,7 +576,7 @@ exports[`EuiPageHeaderContent props tabs is rendered 1`] = `
           type="button"
         >
           <span
-            class="euiTab__content eui-textTruncate emotion-euiTab__content-xl"
+            class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
           >
             Tab 2
           </span>
@@ -604,7 +604,7 @@ exports[`EuiPageHeaderContent props tabs is rendered with tabsProps 1`] = `
       </h1>
       <div
         aria-label="aria-label"
-        class="euiTabs testClass1 testClass2 emotion-euiTabs-xl-euiTestCss"
+        class="euiTabs testClass1 testClass2 emotion-euiTabs-l-euiTestCss"
         data-test-subj="test subject string"
         role="tablist"
       >
@@ -616,7 +616,7 @@ exports[`EuiPageHeaderContent props tabs is rendered with tabsProps 1`] = `
           type="button"
         >
           <span
-            class="euiTab__content eui-textTruncate emotion-euiTab__content-xl"
+            class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
           >
             Tab 1
           </span>
@@ -629,7 +629,7 @@ exports[`EuiPageHeaderContent props tabs is rendered with tabsProps 1`] = `
           type="button"
         >
           <span
-            class="euiTab__content eui-textTruncate emotion-euiTab__content-xl"
+            class="euiTab__content eui-textTruncate emotion-euiTab__content-l"
           >
             Tab 2
           </span>
diff --git a/packages/eui/src/components/page/page_header/page_header_content.tsx b/packages/eui/src/components/page/page_header/page_header_content.tsx
index d99a0e058ef..ef59217e695 100644
--- a/packages/eui/src/components/page/page_header/page_header_content.tsx
+++ b/packages/eui/src/components/page/page_header/page_header_content.tsx
@@ -236,7 +236,7 @@ export const EuiPageHeaderContent: FunctionComponent<
     descriptionNode = (
       <>
         {(pageTitle || tabs) && <EuiSpacer />}
-        <EuiText grow={false}>
+        <EuiText grow={false} size="s">
           <p>{description}</p>
         </EuiText>
       </>
@@ -257,11 +257,11 @@ export const EuiPageHeaderContent: FunctionComponent<
       iconProps?.css,
     ];
     const icon = iconType ? (
-      <EuiIcon size="xl" {...iconProps} css={iconCssStyles} type={iconType} />
+      <EuiIcon size="l" {...iconProps} css={iconCssStyles} type={iconType} />
     ) : undefined;
 
     pageTitleNode = (
-      <EuiTitle {...pageTitleProps} size="l">
+      <EuiTitle {...pageTitleProps} size="m">
         <h1>
           {icon}
           {pageTitle}
@@ -272,7 +272,7 @@ export const EuiPageHeaderContent: FunctionComponent<
 
   let tabsNode;
   if (tabs) {
-    const tabsSize: EuiTabsProps['size'] = pageTitle ? 'l' : 'xl';
+    const tabsSize: EuiTabsProps['size'] = pageTitle ? 'm' : 'l';
 
     const renderTabs = () => {
       return tabs.map((tab, index) => {
@@ -379,7 +379,7 @@ export const EuiPageHeaderContent: FunctionComponent<
 
     rightSideFlexItem = (
       <EuiFlexGroup
-        gutterSize="l"
+        gutterSize="m"
         responsive={false}
         wrap
         {...rightSideGroupProps}