diff --git a/internal/ingress/controller/controller.go b/internal/ingress/controller/controller.go
index 27cd2ffe43..70a075a534 100644
--- a/internal/ingress/controller/controller.go
+++ b/internal/ingress/controller/controller.go
@@ -727,7 +727,7 @@ func (n *NGINXController) getBackendServers(ingresses []*ingress.Ingress) ([]*in
 				endps := getEndpoints(location.DefaultBackend, &sp, apiv1.ProtocolTCP, n.store.GetServiceEndpoints)
 				// custom backend is valid only if contains at least one endpoint
 				if len(endps) > 0 {
-					name := fmt.Sprintf("custom-default-backend-%v", location.DefaultBackend.GetName())
+					name := fmt.Sprintf("custom-default-backend-%v-%v", location.DefaultBackend.GetNamespace(), location.DefaultBackend.GetName())
 					klog.V(3).Infof("Creating \"%v\" upstream based on default backend annotation", name)
 
 					nb := upstream.DeepCopy()
diff --git a/test/e2e/annotations/customhttperrors.go b/test/e2e/annotations/customhttperrors.go
index 6f7c26b3c6..c0115cb524 100644
--- a/test/e2e/annotations/customhttperrors.go
+++ b/test/e2e/annotations/customhttperrors.go
@@ -116,7 +116,7 @@ var _ = framework.DescribeAnnotation("custom-http-errors", func() {
 			}
 			return false
 		})
-		assert.Contains(ginkgo.GinkgoT(), serverConfig, errorBlockName(fmt.Sprintf("custom-default-backend-%s", customDefaultBackend), "503"))
-		assert.Contains(ginkgo.GinkgoT(), serverConfig, fmt.Sprintf("error_page %s = %s", "503", errorBlockName(fmt.Sprintf("custom-default-backend-%s", customDefaultBackend), "503")))
+		assert.Contains(ginkgo.GinkgoT(), serverConfig, errorBlockName(fmt.Sprintf("custom-default-backend-%s-%s", f.Namespace, customDefaultBackend), "503"))
+		assert.Contains(ginkgo.GinkgoT(), serverConfig, fmt.Sprintf("error_page %s = %s", "503", errorBlockName(fmt.Sprintf("custom-default-backend-%s-%s", f.Namespace, customDefaultBackend), "503")))
 	})
 })