diff --git a/AppImage/components/backup-storage-retention.tsx b/AppImage/components/backup-storage-retention.tsx
index f27ae046..4d15c6a5 100644
--- a/AppImage/components/backup-storage-retention.tsx
+++ b/AppImage/components/backup-storage-retention.tsx
@@ -23,6 +23,7 @@ export function BackupStorageRetention() {
   const [editing, setEditing] = useState<StorageRetention | null>(null)
   const [fields, setFields] = useState<Record<string, string>>({})
   const [keepAll, setKeepAll] = useState(false)
+  const [useDefault, setUseDefault] = useState(false)
   const [busy, setBusy] = useState(false)
   const [message, setMessage] = useState("")
   const [saveError, setSaveError] = useState("")
@@ -30,7 +31,8 @@ export function BackupStorageRetention() {
   function edit(storage: StorageRetention) {
     const policy = parseRetention(storage.prune_backups)
     setFields(policy.fields)
-    setKeepAll(policy.keepAll || !storage.prune_backups)
+    setKeepAll(policy.keepAll)
+    setUseDefault(!storage.prune_backups)
     setSaveError("")
     setMessage("")
     setEditing(storage)
@@ -38,8 +40,8 @@ export function BackupStorageRetention() {
 
   async function save() {
     if (!editing || busy) return
-    const prune = buildRetention(fields, keepAll)
-    if (!prune) return setSaveError(t("backup.storageRetention.choosePolicy"))
+    const prune = useDefault ? "" : buildRetention(fields, keepAll)
+    if (!useDefault && !prune) return setSaveError(t("backup.storageRetention.choosePolicy"))
     setBusy(true)
     setSaveError("")
     try {
@@ -79,14 +81,18 @@ export function BackupStorageRetention() {
       <DialogContent className="bg-accent [&_input]:bg-background">
         <DialogHeader><DialogTitle>{t("backup.storageRetention.editTitle", { storage: editing?.id ?? "" })}</DialogTitle>
           <DialogDescription>{t("backup.storageRetention.effect")}</DialogDescription></DialogHeader>
-        <Label className="flex items-center gap-2"><Checkbox checked={keepAll} disabled={busy} onCheckedChange={checked => {
+        <Label className="flex items-center gap-2"><Checkbox checked={useDefault} disabled={busy} onCheckedChange={checked => {
+          setUseDefault(checked === true)
+          if (checked) { setKeepAll(false); setFields({}) }
+        }} />{t("backup.storageRetention.useDefault")}</Label>
+        <Label className="flex items-center gap-2"><Checkbox checked={keepAll} disabled={useDefault || busy} onCheckedChange={checked => {
           setKeepAll(checked === true)
           if (checked) setFields({})
         }} />{t("backup.storageRetention.keepAll")}</Label>
         <div className="grid grid-cols-2 gap-3">
           {RETENTION.map(key => <div key={key} className="space-y-1">
-            <Label htmlFor={`storage-retention-${key}`}>{t(`backup.retention.${key}`)}</Label>
-            <Input id={`storage-retention-${key}`} type="number" min={1} max={99999} step={1} disabled={keepAll || busy}
+            <Label htmlFor={`storage-retention-${key}`}>{t(`backup.retention.keep${key[0].toUpperCase()}${key.slice(1)}`)}</Label>
+            <Input id={`storage-retention-${key}`} type="number" min={1} max={99999} step={1} disabled={useDefault || keepAll || busy}
               value={fields[key] ?? ""} onChange={event => setFields(previous => ({ ...previous, [key]: event.target.value }))} />
           </div>)}
         </div>
diff --git a/AppImage/messages/en/common.json b/AppImage/messages/en/common.json
index 712f3b94..b8aff9b4 100644
--- a/AppImage/messages/en/common.json
+++ b/AppImage/messages/en/common.json
@@ -3948,6 +3948,7 @@
   },
   "backup": {
     "storageRetention": {
+      "useDefault": "Use the Proxmox default (no policy on this storage)",
       "title": "Storage retention",
       "keepAll": "Keep all backups",
       "description": "Default backup retention stored in Proxmox. Backup jobs with an explicit policy override this default.",
diff --git a/AppImage/messages/es/common.json b/AppImage/messages/es/common.json
index a47ff1d5..7314cd0f 100644
--- a/AppImage/messages/es/common.json
+++ b/AppImage/messages/es/common.json
@@ -4764,19 +4764,20 @@
       "wednesday": "Miércoles"
     },
     "storageRetention": {
+      "useDefault": "Usar el valor por defecto de Proxmox (sin política en este almacenamiento)",
       "title": "Retención del almacenamiento",
-      "keepAll": "Conservar todas las copias de seguridad",
-      "description": "Retención de copias de seguridad predeterminada guardada en Proxmox. Las tareas de copia con una política explícita tienen prioridad sobre este valor.",
+      "keepAll": "Conservar todos los backups",
+      "description": "Retención por defecto de los backups, guardada en Proxmox. Las tareas de backup con su propia política tienen prioridad sobre ella.",
       "refresh": "Actualizar",
-      "saved": "Retención del almacenamiento guardada. No se ha ejecutado ninguna purga.",
-      "choosePolicy": "Elige Conservar todas o al menos un número de retención mayor que cero.",
+      "saved": "Retención guardada. No se ha purgado ningún backup.",
+      "choosePolicy": "Elige Conservar todos o al menos un número de retención mayor que cero.",
       "saveFailed": "No se pudo guardar la retención del almacenamiento. Actualiza la lista si ha cambiado la configuración.",
       "loadFailed": "No se pudo cargar la retención del almacenamiento.",
-      "empty": "No se han encontrado almacenamientos de copias de seguridad.",
-      "default": "Valor predeterminado de Proxmox",
+      "empty": "No hay almacenamientos de backups.",
+      "default": "Valor por defecto de Proxmox",
       "edit": "Editar",
       "editTitle": "Retención de {storage}",
-      "effect": "Se aplica a las futuras copias de seguridad que hereden esta política de almacenamiento. Guardar no elimina las copias existentes. Las copias protegidas mantienen su protección.",
+      "effect": "Se aplica a los próximos backups que hereden la política de este almacenamiento. Guardar no elimina los backups existentes, y los protegidos siguen protegidos.",
       "cancel": "Cancelar",
       "save": "Guardar retención"
     }
diff --git a/AppImage/scripts/flask_vm_backup_routes.py b/AppImage/scripts/flask_vm_backup_routes.py
index e1259a2c..78e77919 100644
--- a/AppImage/scripts/flask_vm_backup_routes.py
+++ b/AppImage/scripts/flask_vm_backup_routes.py
@@ -259,13 +259,14 @@ def update_backup_storage_retention(storage_id):
     digest, prune = data.get("digest"), data.get("prune_backups")
     if not isinstance(digest, str) or not re.fullmatch(r"[a-fA-F0-9]{40}", digest):
         return _err("Refresh the storage list before editing its retention")
-    if not isinstance(prune, str) or not PRUNE_RE.fullmatch(prune):
+    # An empty policy removes the storage setting, so the Proxmox default applies.
+    if not isinstance(prune, str) or (prune and not PRUNE_RE.fullmatch(prune)):
         return _err("Invalid retention policy")
-    pairs = [part.split("=", 1) for part in prune.split(",")]
+    pairs = [part.split("=", 1) for part in prune.split(",")] if prune else []
     keys = [key for key, _ in pairs]
     if (len(keys) != len(set(keys)) or
             ("keep-all" in keys and (len(keys) != 1 or pairs[0][1] != "1")) or
-            not any(int(value) > 0 for _, value in pairs)):
+            any(int(value) < 1 for _, value in pairs)):
         return _err("Choose keep-all=1 or one or more positive retention counts")
     # Check that this is still a backup storage, then let Proxmox check the
     # digest under its storage lock. Other storage settings are never passed.
@@ -276,7 +277,8 @@ def update_backup_storage_retention(storage_id):
         return _err("This storage does not accept backups", 409)
     if storage.get("digest") != digest:
         return _err("Storage configuration changed; refresh before saving", 409)
-    ok, out = _pvesh(["set", f"/storage/{storage_id}", "--digest", digest, "--prune-backups", prune])
+    change = ["--prune-backups", prune] if prune else ["--delete", "prune-backups"]
+    ok, out = _pvesh(["set", f"/storage/{storage_id}", "--digest", digest, *change])
     if not ok:
         return _err(out, 409)
     return jsonify({"success": True})
diff --git a/tests/test_vm_backup_jobs_api.py b/tests/test_vm_backup_jobs_api.py
index c9f7b12b..b5e50396 100644
--- a/tests/test_vm_backup_jobs_api.py
+++ b/tests/test_vm_backup_jobs_api.py
@@ -130,9 +130,13 @@ class VmBackupJobsApiTests(unittest.TestCase):
         self.assertEqual(self.storage_policy("keep-all=1").status_code, 200)
         self.assertEqual(self.changes()[0][-1], "keep-all=1")
 
+    def test_an_empty_policy_returns_the_storage_to_the_proxmox_default(self):
+        self.assertEqual(self.storage_policy("").status_code, 200)
+        self.assertEqual(self.changes(), [["set", "/storage/local", "--digest", "a" * 40, "--delete", "prune-backups"]])
+
     def test_invalid_storage_retention_is_rejected_before_commands(self):
         invalid = [None, [], {}, {"digest": "a" * 40, "prune_backups": []}]
-        for prune in ("", "keep-last=-1", "keep-all=0", "keep-all=2", "keep-last=0", "keep-last=1,keep-last=2",
+        for prune in ("keep-last=3,keep-daily=0", "keep-last=-1", "keep-all=0", "keep-all=2", "keep-last=0", "keep-last=1,keep-last=2",
                       "keep-all=1,keep-last=2", "keep-last=2 --delete path", "keep-last=1\n", "keep-other=1"):
             invalid.append({"digest": "a" * 40, "prune_backups": prune})
         invalid += [{"digest": "invalid", "prune_backups": "keep-last=1"}]