diff --git a/.changeset/light-jokes-sleep.md b/.changeset/light-jokes-sleep.md
new file mode 100644
index 0000000000..bd5d728b69
--- /dev/null
+++ b/.changeset/light-jokes-sleep.md
@@ -0,0 +1,5 @@
+---
+'@openproject/primer-view-components': patch
+---
+
+Make the large header variant the default for OpenProject::PageHeader
diff --git a/app/components/primer/open_project/page_header.rb b/app/components/primer/open_project/page_header.rb
index 9dbbff1012..51bf6fbebb 100644
--- a/app/components/primer/open_project/page_header.rb
+++ b/app/components/primer/open_project/page_header.rb
@@ -7,16 +7,16 @@ class PageHeader < Primer::Component
       HEADING_TAG_OPTIONS = [:h1, :h2, :h3, :h4, :h5, :h6].freeze
       HEADING_TAG_FALLBACK = :h2
 
-      DEFAULT_HEADER_VARIANT = :medium
+      DEFAULT_HEADER_VARIANT = :large
       HEADER_VARIANT_OPTIONS = [
-        :large,
+        :medium,
         DEFAULT_HEADER_VARIANT
       ].freeze
 
       DEFAULT_BACK_BUTTON_SIZE = :medium
       BACK_BUTTON_SIZE_OPTIONS = [
         :small,
-        DEFAULT_HEADER_VARIANT,
+        DEFAULT_BACK_BUTTON_SIZE,
         :large
       ].freeze
 
diff --git a/previews/primer/open_project/page_header_preview.rb b/previews/primer/open_project/page_header_preview.rb
index 258a17a872..e0ff8f8968 100644
--- a/previews/primer/open_project/page_header_preview.rb
+++ b/previews/primer/open_project/page_header_preview.rb
@@ -25,7 +25,7 @@ def default
       # @param with_context_bar_actions [Boolean]
       # @param with_parent_link [Boolean]
       def playground(
-        variant: :medium,
+        variant: :large,
         title: "Hello",
         description: "Last updated 5 minutes ago by XYZ.",
         with_back_button: false,
@@ -49,10 +49,10 @@ def playground(
                                        breadcrumb_items: breadcrumb_items })
       end
 
-      # @label Large
-      def large_title
+      # @label Medium title
+      def medium_title
         render(Primer::OpenProject::PageHeader.new) do |header|
-          header.with_title(variant: :large) { "Hello" }
+          header.with_title(variant: :medium) { "Hello" }
           header.with_description { "Last updated 5 minutes ago by XYZ." }
         end
       end
diff --git a/test/components/primer/open_project/page_header_test.rb b/test/components/primer/open_project/page_header_test.rb
index 06cab5fb3a..58a906f432 100644
--- a/test/components/primer/open_project/page_header_test.rb
+++ b/test/components/primer/open_project/page_header_test.rb
@@ -16,14 +16,15 @@ def test_renders_title
 
     assert_text("Hello")
     assert_selector(".PageHeader-title")
+    assert_selector(".PageHeader-title--large")
   end
 
-  def test_renders_large_title
-    render_inline(Primer::OpenProject::PageHeader.new) { |header| header.with_title(variant: :large) { "Hello" } }
+  def test_renders_medium_title
+    render_inline(Primer::OpenProject::PageHeader.new) { |header| header.with_title(variant: :medium) { "Hello" } }
 
     assert_text("Hello")
     assert_selector(".PageHeader-title")
-    assert_selector(".PageHeader-title--large")
+    assert_selector(".PageHeader-title--medium")
   end
 
   def test_renders_description