diff --git a/superset-frontend/src/features/databases/DatabaseModal/index.tsx b/superset-frontend/src/features/databases/DatabaseModal/index.tsx
index 0919941938a..1fa38c5e152 100644
--- a/superset-frontend/src/features/databases/DatabaseModal/index.tsx
+++ b/superset-frontend/src/features/databases/DatabaseModal/index.tsx
@@ -35,7 +35,6 @@ import { CheckboxChangeEvent } from '@superset-ui/core/components/Checkbox/types
 
 import { useHistory } from 'react-router-dom';
 import { setItem, LocalStorageKeys } from 'src/utils/localStorageHelpers';
-import { makeUrl } from 'src/utils/pathUtils';
 import Tabs from '@superset-ui/core/components/Tabs';
 import {
   Button,
@@ -1824,7 +1823,9 @@ const DatabaseModal: FunctionComponent<DatabaseModalProps> = ({
         onClick={() => {
           setLoading(true);
           fetchAndSetDB();
-          redirectURL(makeUrl(`/sqllab?db=true`));
+          // redirectURL() delegates to history.push; React Router's basename
+          // already prefixes the application root, so pass a relative path.
+          redirectURL('/sqllab?db=true');
         }}
       >
         {t('Query data in SQL Lab')}
diff --git a/superset-frontend/src/features/home/EmptyState.tsx b/superset-frontend/src/features/home/EmptyState.tsx
index 119fd6596ce..436f8181f5b 100644
--- a/superset-frontend/src/features/home/EmptyState.tsx
+++ b/superset-frontend/src/features/home/EmptyState.tsx
@@ -24,7 +24,6 @@ import { TableTab } from 'src/views/CRUD/types';
 import { t } from '@apache-superset/core/translation';
 import { styled } from '@apache-superset/core/theme';
 import { navigateTo } from 'src/utils/navigationUtils';
-import { makeUrl } from 'src/utils/pathUtils';
 import { WelcomeTable } from './types';
 
 const EmptyContainer = styled.div`
@@ -59,7 +58,9 @@ const REDIRECTS = {
   create: {
     [WelcomeTable.Charts]: '/chart/add',
     [WelcomeTable.Dashboards]: '/dashboard/new',
-    [WelcomeTable.SavedQueries]: makeUrl('/sqllab?new=true'),
+    // navigateTo() applies the application root internally; keep this
+    // relative so the prefix isn't added twice.
+    [WelcomeTable.SavedQueries]: '/sqllab?new=true',
   },
   viewAll: {
     [WelcomeTable.Charts]: '/chart/list',
diff --git a/superset-frontend/src/features/home/RightMenu.tsx b/superset-frontend/src/features/home/RightMenu.tsx
index 28c25498642..6462c1c588b 100644
--- a/superset-frontend/src/features/home/RightMenu.tsx
+++ b/superset-frontend/src/features/home/RightMenu.tsx
@@ -44,7 +44,7 @@ import {
   TelemetryPixel,
 } from '@superset-ui/core/components';
 import type { ItemType, MenuItem } from '@superset-ui/core/components/Menu';
-import { ensureAppRoot, makeUrl } from 'src/utils/pathUtils';
+import { ensureAppRoot } from 'src/utils/pathUtils';
 import { isEmbedded } from 'src/dashboard/util/isEmbedded';
 import { findPermission } from 'src/utils/findPermission';
 import { isUserAdmin } from 'src/dashboard/util/permissionUtils';
@@ -213,7 +213,10 @@ const RightMenu = ({
     },
     {
       label: t('SQL query'),
-      url: makeUrl('/sqllab?new=true'),
+      // Keep the URL relative so isFrontendRoute() matches and Link navigates
+      // via React Router; the <Typography.Link> fallback applies ensureAppRoot
+      // exactly once for non-frontend routes.
+      url: '/sqllab?new=true',
       icon: <Icons.SearchOutlined data-test={`menu-item-${t('SQL query')}`} />,
       perm: 'can_sqllab',
       view: 'Superset',
diff --git a/superset-frontend/src/pages/SavedQueryList/SavedQueryList.test.tsx b/superset-frontend/src/pages/SavedQueryList/SavedQueryList.test.tsx
index 12cf7e6aba7..9fcb399e7e2 100644
--- a/superset-frontend/src/pages/SavedQueryList/SavedQueryList.test.tsx
+++ b/superset-frontend/src/pages/SavedQueryList/SavedQueryList.test.tsx
@@ -25,11 +25,20 @@ import {
   fireEvent,
   waitFor,
 } from 'spec/helpers/testing-library';
-import { MemoryRouter } from 'react-router-dom';
+import { MemoryRouter, useLocation } from 'react-router-dom';
 import { QueryParamProvider } from 'use-query-params';
 import { ReactRouter5Adapter } from 'use-query-params/adapters/react-router-5';
+import * as getBootstrapData from 'src/utils/getBootstrapData';
 import SavedQueryList from '.';
 
+// Renders the current router pathname+search so tests can assert navigation.
+function LocationDisplay() {
+  const location = useLocation();
+  return (
+    <div data-test="location-display">{`${location.pathname}${location.search}`}</div>
+  );
+}
+
 // Increase default timeout
 jest.setTimeout(30000);
 
@@ -88,6 +97,7 @@ const renderList = (props = {}, storeOverrides = {}) =>
     <MemoryRouter>
       <QueryParamProvider adapter={ReactRouter5Adapter}>
         <SavedQueryList user={mockUser} {...props} />
+        <LocationDisplay />
       </QueryParamProvider>
     </MemoryRouter>,
     {
@@ -242,4 +252,39 @@ describe('SavedQueryList', () => {
     // Verify delete buttons are not shown
     expect(screen.queryByTestId('delete-action')).not.toBeInTheDocument();
   });
+
+  test('"+ Query" button pushes a router-relative path (subdirectory deployment)', async () => {
+    // Simulate SUPERSET_APP_ROOT=/superset. ensureAppRoot/makeUrl read
+    // applicationRoot() dynamically, so mocking it here makes the buggy code
+    // path (makeUrl() around history.push) produce '/superset/sqllab?new=true'
+    // instead of being a no-op. React Router's <Router basename> prefixes the
+    // app root on its own, so history.push MUST receive a path without the
+    // app-root prefix — otherwise navigation lands at /superset/superset/sqllab
+    // and shows a blank page (sc-103661).
+    const applicationRootSpy = jest
+      .spyOn(getBootstrapData, 'applicationRoot')
+      .mockReturnValue('/superset');
+
+    try {
+      renderList();
+
+      await screen.findByTestId('saved_query-list-view');
+
+      const queryButton = await screen.findByRole('button', {
+        name: /query/i,
+      });
+      fireEvent.click(queryButton);
+
+      await waitFor(() => {
+        // The MemoryRouter in renderList uses the default ('/') basename, so
+        // useLocation reflects exactly what history.push received. A correct
+        // router-relative push produces '/sqllab?new=true'; a buggy push that
+        // re-applied the app root would produce '/superset/sqllab?new=true'.
+        const location = screen.getByTestId('location-display').textContent;
+        expect(location).toBe('/sqllab?new=true');
+      });
+    } finally {
+      applicationRootSpy.mockRestore();
+    }
+  });
 });
diff --git a/superset-frontend/src/pages/SavedQueryList/index.tsx b/superset-frontend/src/pages/SavedQueryList/index.tsx
index 65797e69b96..1010585eb37 100644
--- a/superset-frontend/src/pages/SavedQueryList/index.tsx
+++ b/superset-frontend/src/pages/SavedQueryList/index.tsx
@@ -223,7 +223,9 @@ function SavedQueryList({
     name: t('Query'),
     buttonStyle: 'primary',
     onClick: () => {
-      history.push(makeUrl('/sqllab?new=true'));
+      // React Router's basename already includes the application root; passing
+      // a relative path ensures correct navigation under subdirectory deployments.
+      history.push('/sqllab?new=true');
     },
   });
 
@@ -245,7 +247,9 @@ function SavedQueryList({
     if (openInNewWindow) {
       window.open(makeUrl(`/sqllab?savedQueryId=${id}`));
     } else {
-      history.push(makeUrl(`/sqllab?savedQueryId=${id}`));
+      // React Router's basename already includes the application root; passing
+      // a relative path ensures correct navigation under subdirectory deployments.
+      history.push(`/sqllab?savedQueryId=${id}`);
     }
   };
 
@@ -338,9 +342,7 @@ function SavedQueryList({
           row: {
             original: { id, label },
           },
-        }: any) => (
-          <Link to={makeUrl(`/sqllab?savedQueryId=${id}`)}>{label}</Link>
-        ),
+        }: any) => <Link to={`/sqllab?savedQueryId=${id}`}>{label}</Link>,
         id: 'label',
       },
       {