diff --git a/homeassistant/components/esphome/entry_data.py b/homeassistant/components/esphome/entry_data.py
index 8d3e2ff1547a..7dd004c2af83 100644
--- a/homeassistant/components/esphome/entry_data.py
+++ b/homeassistant/components/esphome/entry_data.py
@@ -166,6 +166,8 @@ class RuntimeEntryData:
     )
     loaded_platforms: set[Platform] = field(default_factory=set)
     platform_load_lock: asyncio.Lock = field(default_factory=asyncio.Lock)
+    # Set once the first connection has finished scanner setup or teardown.
+    first_connect_done: asyncio.Event = field(default_factory=asyncio.Event)
     _storage_contents: StoreData | None = None
     _pending_storage: Callable[[], StoreData] | None = None
     assist_pipeline_update_callbacks: list[CALLBACK_TYPE] = field(default_factory=list)
diff --git a/homeassistant/components/esphome/manager.py b/homeassistant/components/esphome/manager.py
index 2a6d38471722..3eeaed77be5e 100644
--- a/homeassistant/components/esphome/manager.py
+++ b/homeassistant/components/esphome/manager.py
@@ -1,11 +1,12 @@
 """Manager for esphome devices."""
 
+import asyncio
 import base64
 from functools import partial
 import logging
 import secrets
 import struct
-from typing import TYPE_CHECKING, Any, NamedTuple
+from typing import TYPE_CHECKING, Any, Final, NamedTuple
 
 from aioesphomeapi import (
     APIClient,
@@ -106,6 +107,9 @@ if TYPE_CHECKING:
 
 _LOGGER = logging.getLogger(__name__)
 
+# Max time to wait at startup for a BLE proxy to register its scanner.
+STARTUP_SCANNER_WAIT: Final = 3.0
+
 LOG_LEVEL_TO_LOGGER = {
     LogLevel.LOG_LEVEL_NONE: logging.DEBUG,
     LogLevel.LOG_LEVEL_ERROR: logging.ERROR,
@@ -677,6 +681,8 @@ class ESPHomeManager:
                 hass, device_info.bluetooth_mac_address or device_info.mac_address
             )
 
+        entry_data.first_connect_done.set()
+
         if device_info.voice_assistant_feature_flags_compat(api_version) and (
             Platform.ASSIST_SATELLITE not in entry_data.loaded_platforms
         ):
@@ -988,6 +994,21 @@ class ESPHomeManager:
 
         await reconnect_logic.start()
 
+        # Wait for a cached BLE proxy to register its scanner before finishing setup.
+        if (
+            device_info := entry_data.device_info
+        ) is not None and device_info.bluetooth_proxy_feature_flags_compat(
+            entry_data.api_version
+        ):
+            try:
+                async with asyncio.timeout(STARTUP_SCANNER_WAIT):
+                    await entry_data.first_connect_done.wait()
+            except TimeoutError:
+                _LOGGER.debug(
+                    "%s: Timed out waiting for Bluetooth scanner to register",
+                    self.host,
+                )
+
 
 @callback
 def _async_setup_device_registry(
diff --git a/tests/components/esphome/test_manager.py b/tests/components/esphome/test_manager.py
index 89a42e9aadf9..96ffcb52d3b7 100644
--- a/tests/components/esphome/test_manager.py
+++ b/tests/components/esphome/test_manager.py
@@ -9,7 +9,9 @@ from unittest.mock import AsyncMock, Mock, call, patch
 from aioesphomeapi import (
     APIClient,
     APIConnectionError,
+    APIVersion,
     AreaInfo,
+    BluetoothProxyFeature,
     DeviceInfo,
     EncryptionPlaintextAPIError,
     ExecuteServiceResponse,
@@ -3274,3 +3276,124 @@ async def test_service_registration_response_types(
         hass.services.supports_response(DOMAIN, "test_status_service")
         == SupportsResponse.NONE
     )
+
+
+def _create_cached_bluetooth_proxy_entry(
+    hass: HomeAssistant,
+    hass_storage: dict[str, Any],
+    bluetooth_proxy_feature_flags: BluetoothProxyFeature,
+) -> tuple[MockConfigEntry, DeviceInfo]:
+    """Create an entry with cached device info so setup knows the proxy state."""
+    entry = MockConfigEntry(
+        domain=DOMAIN,
+        unique_id="11:22:33:44:55:aa",
+        data={
+            CONF_HOST: "test.local",
+            CONF_PORT: 6053,
+            CONF_PASSWORD: "",
+            CONF_BLUETOOTH_MAC_ADDRESS: "AA:BB:CC:DD:EE:FC",
+        },
+    )
+    entry.add_to_hass(hass)
+    device_info = DeviceInfo(
+        name="test",
+        mac_address="11:22:33:44:55:AA",
+        bluetooth_mac_address="AA:BB:CC:DD:EE:FC",
+        bluetooth_proxy_feature_flags=bluetooth_proxy_feature_flags,
+    )
+    storage_key = f"{DOMAIN}.{entry.entry_id}"
+    hass_storage[storage_key] = {
+        "version": 1,
+        "minor_version": 1,
+        "key": storage_key,
+        "data": {
+            "device_info": device_info.to_dict(),
+            "api_version": APIVersion(1, 9).to_dict(),
+        },
+    }
+    return entry, device_info
+
+
+@pytest.mark.usefixtures("mock_zeroconf")
+async def test_bluetooth_proxy_waits_for_scanner_at_startup(
+    hass: HomeAssistant,
+    mock_client: APIClient,
+    hass_storage: dict[str, Any],
+) -> None:
+    """Test setup waits for a cached bluetooth proxy to register its scanner."""
+    entry, device_info = _create_cached_bluetooth_proxy_entry(
+        hass, hass_storage, BluetoothProxyFeature.PASSIVE_SCAN
+    )
+    connect_event = asyncio.Event()
+    reached_connect = asyncio.Event()
+
+    async def _block_until_released() -> tuple[DeviceInfo, list[Any], list[Any]]:
+        reached_connect.set()
+        await connect_event.wait()
+        return (device_info, [], [])
+
+    mock_client.device_info_and_list_entities = _block_until_released
+
+    setup_task = hass.async_create_task(hass.config_entries.async_setup(entry.entry_id))
+    async with asyncio.timeout(2):
+        await reached_connect.wait()
+
+    # Setup must still be waiting for the scanner to be registered.
+    assert not setup_task.done()
+
+    connect_event.set()
+    async with asyncio.timeout(2):
+        assert await setup_task is True
+    assert entry.runtime_data.first_connect_done.is_set()
+
+
+@pytest.mark.usefixtures("mock_zeroconf")
+async def test_bluetooth_proxy_startup_wait_times_out(
+    hass: HomeAssistant,
+    mock_client: APIClient,
+    hass_storage: dict[str, Any],
+) -> None:
+    """Test setup finishes if a cached bluetooth proxy never connects."""
+    entry, device_info = _create_cached_bluetooth_proxy_entry(
+        hass, hass_storage, BluetoothProxyFeature.PASSIVE_SCAN
+    )
+    connect_event = asyncio.Event()
+
+    async def _never_returns() -> tuple[DeviceInfo, list[Any], list[Any]]:
+        await connect_event.wait()
+        return (device_info, [], [])
+
+    mock_client.device_info_and_list_entities = _never_returns
+
+    with patch("homeassistant.components.esphome.manager.STARTUP_SCANNER_WAIT", 0.05):
+        async with asyncio.timeout(2):
+            assert await hass.config_entries.async_setup(entry.entry_id) is True
+
+    connect_event.set()
+    await hass.async_block_till_done()
+
+
+@pytest.mark.usefixtures("mock_zeroconf")
+async def test_non_bluetooth_device_does_not_wait_at_startup(
+    hass: HomeAssistant,
+    mock_client: APIClient,
+    hass_storage: dict[str, Any],
+) -> None:
+    """Test setup does not wait for a device that is not a bluetooth proxy."""
+    entry, device_info = _create_cached_bluetooth_proxy_entry(
+        hass, hass_storage, BluetoothProxyFeature(0)
+    )
+    connect_event = asyncio.Event()
+
+    async def _never_returns() -> tuple[DeviceInfo, list[Any], list[Any]]:
+        await connect_event.wait()
+        return (device_info, [], [])
+
+    mock_client.device_info_and_list_entities = _never_returns
+
+    # The connection is blocked, but without proxy flags setup must not wait.
+    async with asyncio.timeout(2):
+        assert await hass.config_entries.async_setup(entry.entry_id) is True
+
+    connect_event.set()
+    await hass.async_block_till_done()