diff --git a/kcms/notifications/package/contents/ui/main.qml b/kcms/notifications/package/contents/ui/main.qml
--- a/kcms/notifications/package/contents/ui/main.qml
+++ b/kcms/notifications/package/contents/ui/main.qml
@@ -33,6 +33,8 @@
     // Sidebar on SourcesPage is 1/3 of the width at a minimum of 12, so assume 3 * 12 = 36 as preferred
     implicitWidth: Kirigami.Units.gridUnit * 36
 
+    readonly property NotificationManager.ServerInfo currentOwnerInfo: NotificationManager.Server.currentOwner
+
     function openSourcesSettings() {
         // TODO would be nice to re-use the current SourcesPage instead of pushing a new one that lost all state
         // but there's no pageAt(index) method in KConfigModuleQml
@@ -46,6 +48,31 @@
     }
 
     Kirigami.FormLayout {
+        Kirigami.InlineMessage {
+            Kirigami.FormData.isSection: true
+            Layout.fillWidth: true
+            type: Kirigami.MessageType.Error
+            text: i18n("Could not find a 'Notifications' widget which is required for displaying notifications.");
+            visible: currentOwnerInfo.status === NotificationManager.ServerInfo.NotRunning
+        }
+
+        Kirigami.InlineMessage {
+            Kirigami.FormData.isSection: true
+            Layout.fillWidth: true
+            type: Kirigami.MessageType.Information
+            text: {
+                if (currentOwnerInfo.vendor && currentOwnerInfo.name) {
+                    return i18nc("Vendor and product name",
+                                 "Notifications are currently provided by '%1 %2' instead of Plasma.",
+                                 currentOwnerInfo.vendor, currentOwnerInfo.name);
+                }
+
+                return i18n("Notifications are currently not provided by Plasma.");
+            }
+            visible: root.currentOwnerInfo.status === NotificationManager.ServerInfo.Running
+                && (currentOwnerInfo.vendor !== "KDE" || currentOwnerInfo.name !== "Plasma")
+        }
+
         QtControls.CheckBox {
             Kirigami.FormData.label: i18n("Do not disturb:")
             text: i18nc("Do not disturb when screens are mirrored", "When screens are mirrored")