diff --git a/flow-server/src/main/java/com/vaadin/flow/router/internal/RouteUtil.java b/flow-server/src/main/java/com/vaadin/flow/router/internal/RouteUtil.java
index 461b6e3695d..f9c25539a8c 100644
--- a/flow-server/src/main/java/com/vaadin/flow/router/internal/RouteUtil.java
+++ b/flow-server/src/main/java/com/vaadin/flow/router/internal/RouteUtil.java
@@ -641,7 +641,9 @@ public static void checkForClientRouteCollisions(VaadinService service,
         List<String> collisions = MenuRegistry
                 .collectClientMenuItems(false,
                         service.getDeploymentConfiguration())
-                .keySet().stream().map(PathUtil::trimPath)
+                .entrySet().stream()
+                .filter(entry -> entry.getValue().children() == null)
+                .map(Map.Entry::getKey).map(PathUtil::trimPath)
                 .filter(clientRoute -> Arrays.stream(flowRouteTemplates)
                         .map(PathUtil::trimPath).anyMatch(clientRoute::equals))
                 .toList();
diff --git a/flow-server/src/test/java/com/vaadin/flow/router/internal/RouteUtilTest.java b/flow-server/src/test/java/com/vaadin/flow/router/internal/RouteUtilTest.java
index 2e9c9597165..319c0583a79 100644
--- a/flow-server/src/test/java/com/vaadin/flow/router/internal/RouteUtilTest.java
+++ b/flow-server/src/test/java/com/vaadin/flow/router/internal/RouteUtilTest.java
@@ -15,7 +15,9 @@
  */
 package com.vaadin.flow.router.internal;
 
+import java.io.File;
 import java.lang.reflect.Field;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -25,22 +27,34 @@
 import org.hamcrest.MatcherAssert;
 import org.hamcrest.collection.IsIterableContainingInOrder;
 import org.junit.Assert;
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.mockito.MockedStatic;
+import org.mockito.Mockito;
 
 import com.vaadin.flow.component.Component;
 import com.vaadin.flow.component.Tag;
+import com.vaadin.flow.function.DeploymentConfiguration;
 import com.vaadin.flow.internal.ReflectTools;
+import com.vaadin.flow.internal.menu.MenuRegistry;
 import com.vaadin.flow.router.Layout;
+import com.vaadin.flow.router.Menu;
 import com.vaadin.flow.router.ParentLayout;
 import com.vaadin.flow.router.Route;
 import com.vaadin.flow.router.RouteAlias;
 import com.vaadin.flow.router.RouteConfiguration;
 import com.vaadin.flow.router.RoutePrefix;
 import com.vaadin.flow.router.RouterLayout;
+import com.vaadin.flow.server.InvalidRouteConfigurationException;
 import com.vaadin.flow.server.MockVaadinContext;
 import com.vaadin.flow.server.MockVaadinServletService;
 import com.vaadin.flow.server.SessionRouteRegistry;
 import com.vaadin.flow.server.VaadinContext;
+import com.vaadin.flow.server.VaadinService;
+import com.vaadin.flow.server.frontend.BundleUtils;
+import com.vaadin.flow.server.frontend.FrontendUtils;
+import com.vaadin.flow.server.menu.AvailableViewInfo;
 import com.vaadin.flow.server.startup.ApplicationRouteRegistry;
 import com.vaadin.tests.util.AlwaysLockedVaadinSession;
 
@@ -50,6 +64,9 @@
  */
 public class RouteUtilTest {
 
+    @Rule
+    public ExpectedException expectedEx = ExpectedException.none();
+
     @Tag(Tag.DIV)
     public static class Parent extends Component implements RouterLayout {
     }
@@ -1017,6 +1034,87 @@ class View extends Component {
                 registry.hasLayout("auto"));
     }
 
+    @Test
+    public void clientHasMappedLayout_validateNoClientRouteCollisions() {
+        Map<String, AvailableViewInfo> clientRoutes = new HashMap<>();
+
+        clientRoutes.put("", new AvailableViewInfo("public", null, false, "",
+                false, false, null, null, null, false));
+        clientRoutes
+                .put("/flow",
+                        new AvailableViewInfo("public", null, false, "", false,
+                                false, null,
+                                Arrays.asList(new AvailableViewInfo("child",
+                                        null, false, "", false, false, null,
+                                        null, null, false)),
+                                null, false));
+        clientRoutes.put("/hilla/components", new AvailableViewInfo("public",
+                null, false, "", false, false, null, null, null, false));
+        clientRoutes.put("/hilla", new AvailableViewInfo("public", null, false,
+                "", false, false, null, null, null, false));
+
+        try (MockedStatic<MenuRegistry> registry = Mockito
+                .mockStatic(MenuRegistry.class, Mockito.CALLS_REAL_METHODS);
+                MockedStatic<FrontendUtils> frontendUtils = Mockito.mockStatic(
+                        FrontendUtils.class, Mockito.CALLS_REAL_METHODS);) {
+            VaadinService service = Mockito.mock(VaadinService.class);
+            DeploymentConfiguration conf = Mockito
+                    .mock(DeploymentConfiguration.class);
+            Mockito.when(service.getDeploymentConfiguration()).thenReturn(conf);
+            Mockito.when(conf.isProductionMode()).thenReturn(false);
+            Mockito.when(conf.getFrontendFolder())
+                    .thenReturn(Mockito.mock(File.class));
+
+            registry.when(
+                    () -> MenuRegistry.collectClientMenuItems(false, conf))
+                    .thenReturn(clientRoutes);
+            frontendUtils.when(() -> FrontendUtils.isHillaUsed(Mockito.any()))
+                    .thenReturn(true);
+
+            RouteUtil.checkForClientRouteCollisions(service, "flow",
+                    "flow/hello-world", "hilla/flow");
+        }
+    }
+
+    @Test
+    public void clientHasOverlappingTarget_validateClientRouteCollision() {
+        expectedEx.expect(InvalidRouteConfigurationException.class);
+        expectedEx.expectMessage(
+                "Invalid route configuration. The following Hilla route(s) conflict with configured Flow routes: flow");
+        Map<String, AvailableViewInfo> clientRoutes = new HashMap<>();
+
+        clientRoutes.put("", new AvailableViewInfo("public", null, false, "",
+                false, false, null, null, null, false));
+        clientRoutes.put("/flow", new AvailableViewInfo("public", null, false,
+                "", false, false, null, null, null, false));
+        clientRoutes.put("/hilla/components", new AvailableViewInfo("public",
+                null, false, "", false, false, null, null, null, false));
+        clientRoutes.put("/hilla", new AvailableViewInfo("public", null, false,
+                "", false, false, null, null, null, false));
+
+        try (MockedStatic<MenuRegistry> registry = Mockito
+                .mockStatic(MenuRegistry.class, Mockito.CALLS_REAL_METHODS);
+                MockedStatic<FrontendUtils> frontendUtils = Mockito.mockStatic(
+                        FrontendUtils.class, Mockito.CALLS_REAL_METHODS);) {
+            VaadinService service = Mockito.mock(VaadinService.class);
+            DeploymentConfiguration conf = Mockito
+                    .mock(DeploymentConfiguration.class);
+            Mockito.when(service.getDeploymentConfiguration()).thenReturn(conf);
+            Mockito.when(conf.isProductionMode()).thenReturn(false);
+            Mockito.when(conf.getFrontendFolder())
+                    .thenReturn(Mockito.mock(File.class));
+
+            registry.when(
+                    () -> MenuRegistry.collectClientMenuItems(false, conf))
+                    .thenReturn(clientRoutes);
+            frontendUtils.when(() -> FrontendUtils.isHillaUsed(Mockito.any()))
+                    .thenReturn(true);
+
+            RouteUtil.checkForClientRouteCollisions(service, "flow",
+                    "flow/hello-world", "hilla/flow");
+        }
+    }
+
     @SuppressWarnings("unchecked")
     private void tamperLayouts(ApplicationRouteRegistry registry,
             Consumer<Map<String, Class<? extends RouterLayout>>> consumer) {
diff --git a/flow-server/src/test/java/com/vaadin/flow/server/menu/MenuRegistryTest.java b/flow-server/src/test/java/com/vaadin/flow/server/menu/MenuRegistryTest.java
index d4f1555f425..409b1b08dea 100644
--- a/flow-server/src/test/java/com/vaadin/flow/server/menu/MenuRegistryTest.java
+++ b/flow-server/src/test/java/com/vaadin/flow/server/menu/MenuRegistryTest.java
@@ -581,8 +581,8 @@ public static class MyInfo extends Component {
     }
 
     @Tag("div")
-    @Route("hilla")
-    @Menu(title = "hilla")
+    @Route("about")
+    @Menu(title = "about")
     public static class ConflictRoute extends Component {
     }