diff --git a/custom_components/xiaoxiang_bms/bluetooth_handler.py b/custom_components/xiaoxiang_bms/bluetooth_handler.py
index 2bcba99..c2aa36b 100644
--- a/custom_components/xiaoxiang_bms/bluetooth_handler.py
+++ b/custom_components/xiaoxiang_bms/bluetooth_handler.py
@@ -6,6 +6,7 @@ import logging
 import struct
 
 from bleak import BleakClient, BleakError
+from bleak.backends.device import BLEDevice
 
 from .const import (
     FRAME_END,
@@ -42,13 +43,17 @@ class BmsBluetoothHandler:
     def is_connected(self) -> bool:
         return self._client is not None and self._client.is_connected
 
-    async def connect(self) -> None:
-        """Open BLE connection and start notifications."""
+    async def connect(self, ble_device: BLEDevice) -> None:
+        """Open BLE connection and start notifications.
+
+        Accepts a BLEDevice resolved by HA's Bluetooth subsystem so that
+        ESPHome BLE proxies are used transparently alongside local adapters.
+        """
         if self.is_connected:
             return
-        _LOGGER.debug("Connecting to BMS at %s", self._address)
+        _LOGGER.debug("Connecting to BMS at %s (via %s)", self._address, ble_device.name)
         self._client = BleakClient(
-            self._address,
+            ble_device,
             disconnected_callback=self._on_disconnect,
         )
         await self._client.connect()
diff --git a/custom_components/xiaoxiang_bms/coordinator.py b/custom_components/xiaoxiang_bms/coordinator.py
index 7179f29..972b366 100644
--- a/custom_components/xiaoxiang_bms/coordinator.py
+++ b/custom_components/xiaoxiang_bms/coordinator.py
@@ -4,6 +4,7 @@ from __future__ import annotations
 import logging
 from datetime import timedelta
 
+from homeassistant.components.bluetooth import async_ble_device_from_address
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.update_coordinator import DataUpdateCoordinator, UpdateFailed
 
@@ -35,9 +36,22 @@ class BmsCoordinator(DataUpdateCoordinator[dict]):
     # Lifecycle
     # ------------------------------------------------------------------
 
+    def _get_ble_device(self):
+        """Resolve the best available BLE device via HA's Bluetooth subsystem.
+
+        This automatically uses ESPHome BLE proxies if they can reach the BMS
+        and the local adapter cannot (or vice versa).
+        """
+        device = async_ble_device_from_address(self.hass, self.address, connectable=True)
+        if device is None:
+            raise UpdateFailed(
+                f"BMS ({self.address}) not reachable by any Bluetooth adapter or proxy"
+            )
+        return device
+
     async def async_setup(self) -> None:
         """Connect to the BMS. Called once during config entry setup."""
-        await self._handler.connect()
+        await self._handler.connect(self._get_ble_device())
 
     async def async_teardown(self) -> None:
         """Disconnect cleanly. Called on entry unload."""
@@ -52,7 +66,9 @@ class BmsCoordinator(DataUpdateCoordinator[dict]):
         if not self._handler.is_connected:
             _LOGGER.debug("BMS not connected, attempting reconnect…")
             try:
-                await self._handler.connect()
+                await self._handler.connect(self._get_ble_device())
+            except UpdateFailed:
+                raise
             except Exception as exc:
                 raise UpdateFailed(f"BMS reconnect failed: {exc}") from exc