diff --git a/esphome/components/ble_client/ble_client.cpp b/esphome/components/ble_client/ble_client.cpp
index 45c306c23f..7bcc350a31 100644
--- a/esphome/components/ble_client/ble_client.cpp
+++ b/esphome/components/ble_client/ble_client.cpp
@@ -67,6 +67,9 @@ bool BLEClient::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t es
   // A bridge-initiated notify registration must bypass BLEClientBase's
   // REG_FOR_NOTIFY handling: its automatic CCCD write would double the
   // node's own (the neutral contract makes the CCCD the node's job).
+  // The match is by handle: a legacy and a neutral node subscribing the SAME
+  // characteristic on one client is unsupported during the migration window
+  // (each migration removes the legacy half).
   if (event == ESP_GATTC_REG_FOR_NOTIFY_EVT && esp_gattc_if == this->gattc_if_ &&
       this->take_pending_gatt_reg_(param->reg_for_notify.handle)) {
     if (this->pending_notify_regs_ > 0)
@@ -87,7 +90,12 @@ bool BLEClient::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t es
   // Before the legacy fan-out so gatt nodes resolve their handles before any
   // legacy trigger (e.g. on_connect at SEARCH_CMPL) fires - the neutral
   // engine's order.
-  this->dispatch_gatt_event_(event, param);
+  if (!this->dispatch_gatt_event_(event, param)) {
+    // Failed discovery: the link is coming down, so the legacy fan-out must
+    // not observe the event as a connection (the on_connect trigger would
+    // fire into the teardown).
+    return true;
+  }
 #endif
   for (auto *node : this->nodes_)
     node->gattc_event_handler(event, esp_gattc_if, param);
@@ -162,13 +170,12 @@ bool BLEClient::take_pending_gatt_reg_(uint16_t handle) {
   return false;
 }
 
-void BLEClient::dispatch_gatt_event_(esp_gattc_cb_event_t event, esp_ble_gattc_cb_param_t *param) {
+bool BLEClient::dispatch_gatt_event_(esp_gattc_cb_event_t event, esp_ble_gattc_cb_param_t *param) {
   if (this->gatt_nodes_.empty())
-    return;
+    return true;
   switch (event) {
     case ESP_GATTC_SEARCH_CMPL_EVT:
-      this->handle_gatt_search_cmpl_(param->search_cmpl.status);
-      break;
+      return this->handle_gatt_search_cmpl_(param->search_cmpl.status);
     case ESP_GATTC_READ_CHAR_EVT:
     case ESP_GATTC_READ_DESCR_EVT: {
       bool ok = param->read.status == ESP_GATT_OK;
@@ -199,9 +206,12 @@ void BLEClient::dispatch_gatt_event_(esp_gattc_cb_event_t event, esp_ble_gattc_c
     default:
       break;
   }
+  return true;
 }
 
-void BLEClient::handle_gatt_search_cmpl_(esp_gatt_status_t status) {
+// Returns whether the discovery stands: false tears the link down and the
+// caller suppresses the legacy fan-out of the event.
+bool BLEClient::handle_gatt_search_cmpl_(esp_gatt_status_t status) {
   // The base establishes without reading the search status; the neutral
   // contract treats a failed or empty discovery as a failed connection.
   uint16_t service_total = 0;
@@ -217,7 +227,7 @@ void BLEClient::handle_gatt_search_cmpl_(esp_gatt_status_t status) {
              this->address_str(), status, service_total);
     this->register_gatt_failure_();
     this->disconnect();
-    return;
+    return false;
   }
   this->gatt_connected_ = true;
   auto view = table.view();
@@ -227,7 +237,7 @@ void BLEClient::handle_gatt_search_cmpl_(esp_gatt_status_t status) {
       // The node tore the link down; remaining nodes get on_disconnected
       // with no preceding on_connected, so leave a trace of why.
       ESP_LOGW(TAG, "[%s] A node aborted the connection during setup", this->address_str());
-      return;
+      return false;
     }
   }
   // Promote so the legacy release condition can fire; subscriptions the
@@ -236,6 +246,7 @@ void BLEClient::handle_gatt_search_cmpl_(esp_gatt_status_t status) {
     node->node_state = espbt::ClientState::ESTABLISHED;
   this->gatt_consecutive_failures_ = 0;
   this->gatt_hold_off_ms_ = 0;
+  return true;
 }
 
 void BLEClient::register_gatt_failure_() {
diff --git a/esphome/components/ble_client/ble_client.h b/esphome/components/ble_client/ble_client.h
index bd48594ea8..38a1f70dbe 100644
--- a/esphome/components/ble_client/ble_client.h
+++ b/esphome/components/ble_client/ble_client.h
@@ -71,8 +71,8 @@ class BLEClient final : public BLEClientBase {
 #ifdef USE_BLE_CLIENT_GATT_NODES
   int check_gatt_op_(const char *operation, esp_err_t err);
   void register_gatt_failure_();
-  void dispatch_gatt_event_(esp_gattc_cb_event_t event, esp_ble_gattc_cb_param_t *param);
-  void handle_gatt_search_cmpl_(esp_gatt_status_t status);
+  bool dispatch_gatt_event_(esp_gattc_cb_event_t event, esp_ble_gattc_cb_param_t *param);
+  bool handle_gatt_search_cmpl_(esp_gatt_status_t status);
   bool take_pending_gatt_reg_(uint16_t handle);
   void on_disconnect_complete(esp_err_t reason) override;
 #endif