diff --git a/frontend/src/pages/customers/CustomerDetail.tsx b/frontend/src/pages/customers/CustomerDetail.tsx
index 50f56505..6059c9c3 100644
--- a/frontend/src/pages/customers/CustomerDetail.tsx
+++ b/frontend/src/pages/customers/CustomerDetail.tsx
@@ -1296,7 +1296,17 @@ function MetersTab({
     onSuccess: () => queryClient.invalidateQueries({ queryKey: ['customer', customerId] }),
   });
 
-  const filtered = showInactive ? meters : meters.filter((m) => m.isActive);
+  const [showWithoutContracts, setShowWithoutContracts] = useState(false);
+
+  // Liefert true, wenn der Zähler mindestens einem Vertrag zugeordnet ist
+  // (entweder als Hauptzähler oder über die Folgezähler-Kette).
+  const hasAnyContract = (m: Meter) =>
+    (m.energyDetails?.some((ed) => ed.contract) ?? false)
+    || (m.contractMeters?.some((cm) => cm.energyContractDetails?.contract) ?? false);
+
+  const filtered = meters
+    .filter((m) => showInactive ? true : m.isActive)
+    .filter((m) => showWithoutContracts ? true : hasAnyContract(m));
 
   // Sort readings by date (newest first)
   const getSortedReadings = (readings: any[] | undefined) => {
@@ -1329,6 +1339,15 @@ function MetersTab({
           />
           Inaktive anzeigen
         </label>
+        <label className="flex items-center gap-2 text-sm">
+          <input
+            type="checkbox"
+            checked={showWithoutContracts}
+            onChange={(e) => setShowWithoutContracts(e.target.checked)}
+            className="rounded"
+          />
+          Zähler ohne Verträge anzeigen
+        </label>
       </div>
       {canEdit && !hasDeliveryAddress && (
         <div className="mb-4 p-3 bg-yellow-50 border border-yellow-200 rounded-lg text-sm text-yellow-800">