diff --git a/.changeset/fix-tab-match-query-params.md b/.changeset/fix-tab-match-query-params.md
new file mode 100644
index 0000000000..6e01a202f5
--- /dev/null
+++ b/.changeset/fix-tab-match-query-params.md
@@ -0,0 +1,7 @@
+---
+'@backstage/ui': patch
+---
+
+Fixed tab `matchStrategy` matching to ignore query parameters and hash fragments in tab `href` values. Previously, tabs with query params in their `href` (e.g., `/page?group=foo`) would never show as active since matching compared the full `href` string against `location.pathname` which never includes query params.
+
+**Affected components:** Tabs, PluginHeader
diff --git a/packages/ui/src/components/Tabs/Tabs.stories.tsx b/packages/ui/src/components/Tabs/Tabs.stories.tsx
index 2a02bedc8c..fcc919f294 100644
--- a/packages/ui/src/components/Tabs/Tabs.stories.tsx
+++ b/packages/ui/src/components/Tabs/Tabs.stories.tsx
@@ -454,6 +454,51 @@ export const RootPathMatching = meta.story({
   ),
 });
 
+export const HrefWithQueryParams = meta.story({
+  args: {
+    children: '',
+  },
+  render: () => (
+    <MemoryRouter initialEntries={['/cost-insights/dashboard?group=bar']}>
+      <Tabs>
+        <TabList>
+          <Tab
+            id="dashboard"
+            href="/cost-insights/dashboard?group=foo"
+            matchStrategy="prefix"
+          >
+            Dashboard
+          </Tab>
+          <Tab
+            id="alerts"
+            href="/cost-insights/alerts?group=foo"
+            matchStrategy="prefix"
+          >
+            Alerts
+          </Tab>
+        </TabList>
+      </Tabs>
+      <Box mt="6" pl="2">
+        <Text as="p">
+          Current URL: <strong>/cost-insights/dashboard?group=bar</strong>
+        </Text>
+        <Text as="p">
+          Tab hrefs include query params (e.g., ?group=foo) but the current URL
+          has different query params (?group=bar).
+        </Text>
+        <Text as="p">
+          • "Dashboard" tab: IS active — matching ignores query params and
+          compares only the pathname.
+        </Text>
+        <Text as="p">
+          • "Alerts" tab: NOT active — pathname /cost-insights/alerts doesn't
+          match /cost-insights/dashboard.
+        </Text>
+      </Box>
+    </MemoryRouter>
+  ),
+});
+
 export const AutoSelectionOfTabs = meta.story({
   args: {
     children: '',
diff --git a/packages/ui/src/components/Tabs/Tabs.tsx b/packages/ui/src/components/Tabs/Tabs.tsx
index cf6263b9a4..d625d2abf0 100644
--- a/packages/ui/src/components/Tabs/Tabs.tsx
+++ b/packages/ui/src/components/Tabs/Tabs.tsx
@@ -79,6 +79,12 @@ const TabSelectionContext = createContext<TabSelectionContextValue | null>(
   null,
 );
 
+/**
+ * Strips query params and hash from a href, leaving only the pathname.
+ * Tab matching always compares against location.pathname which never includes them.
+ */
+const hrefPathname = (href: string) => href.split('?')[0].split('#')[0];
+
 /**
  * Utility function to determine if a tab should be active based on the matching strategy.
  * This follows the pattern used in WorkaroundNavLink from the sidebar.
@@ -88,18 +94,20 @@ const isTabActive = (
   currentPathname: string,
   matchStrategy: 'exact' | 'prefix',
 ): boolean => {
+  const pathname = hrefPathname(tabHref);
+
   if (matchStrategy === 'exact') {
-    return tabHref === currentPathname;
+    return pathname === currentPathname;
   }
 
   // Prefix matching - similar to WorkaroundNavLink behavior
-  if (tabHref === currentPathname) {
+  if (pathname === currentPathname) {
     return true;
   }
 
   // Check if current path starts with tab href followed by a slash
   // This prevents /foo matching /foobar
-  return currentPathname.startsWith(`${tabHref}/`);
+  return currentPathname.startsWith(`${pathname}/`);
 };
 
 /**
@@ -304,7 +312,7 @@ function RoutedTabEffects({
 
   // Register as active tab when URL matches (for tab selection)
   const isActive = isTabActive(href, location.pathname, matchStrategy);
-  const segmentCount = href.split('/').filter(Boolean).length;
+  const segmentCount = hrefPathname(href).split('/').filter(Boolean).length;
 
   useEffect(() => {
     if (isActive && selectionCtx) {