diff --git a/.changeset/ui-header-breadcrumb-specificity.md b/.changeset/ui-header-breadcrumb-specificity.md
new file mode 100644
index 0000000000..8078a8e459
--- /dev/null
+++ b/.changeset/ui-header-breadcrumb-specificity.md
@@ -0,0 +1,7 @@
+---
+'@backstage/ui': patch
+---
+
+Fixed Header breadcrumb typography so it remains consistent when component styles are loaded in different orders.
+
+**Affected components:** Header
diff --git a/packages/ui/src/components/Header/Header.module.css b/packages/ui/src/components/Header/Header.module.css
index bd41f0e7ec..003f58cf7b 100644
--- a/packages/ui/src/components/Header/Header.module.css
+++ b/packages/ui/src/components/Header/Header.module.css
@@ -128,8 +128,13 @@
     gap: var(--bui-space-1);
   }
 
-  .bui-HeaderBreadcrumbs .bui-HeaderBreadcrumbLink,
-  .bui-HeaderBreadcrumbsSmall .bui-HeaderBreadcrumbLinkSmall {
+  /*
+   * Link variant defaults have the same specificity as these contextual styles.
+   * Repeat the slot class so the Header styles win regardless of stylesheet order.
+   */
+  .bui-HeaderBreadcrumbs .bui-HeaderBreadcrumbLink.bui-HeaderBreadcrumbLink,
+  .bui-HeaderBreadcrumbsSmall
+    .bui-HeaderBreadcrumbLinkSmall.bui-HeaderBreadcrumbLinkSmall {
     max-width: 240px;
     overflow: hidden;
     font-family: var(--bui-font-regular);
@@ -139,11 +144,12 @@
     white-space: nowrap;
   }
 
-  .bui-HeaderBreadcrumbs .bui-HeaderBreadcrumbLink {
+  .bui-HeaderBreadcrumbs .bui-HeaderBreadcrumbLink.bui-HeaderBreadcrumbLink {
     font-size: inherit;
   }
 
-  .bui-HeaderBreadcrumbsSmall .bui-HeaderBreadcrumbLinkSmall {
+  .bui-HeaderBreadcrumbsSmall
+    .bui-HeaderBreadcrumbLinkSmall.bui-HeaderBreadcrumbLinkSmall {
     font-size: var(--bui-font-size-4);
   }