diff --git a/homeassistant/components/vicare/__init__.py b/homeassistant/components/vicare/__init__.py
index 0c87cd6f4fe..ead210e2816 100644
--- a/homeassistant/components/vicare/__init__.py
+++ b/homeassistant/components/vicare/__init__.py
@@ -15,10 +15,12 @@ from PyViCare.PyViCareUtils import (
     PyViCareInvalidCredentialsError,
 )
 
+from homeassistant.components.climate import DOMAIN as DOMAIN_CLIMATE
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import CONF_CLIENT_ID, CONF_PASSWORD, CONF_USERNAME
-from homeassistant.core import HomeAssistant
+from homeassistant.core import HomeAssistant, callback
 from homeassistant.exceptions import ConfigEntryAuthFailed
+from homeassistant.helpers import device_registry as dr, entity_registry as er
 from homeassistant.helpers.storage import STORAGE_DIR
 
 from .const import (
@@ -47,6 +49,12 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
     except (PyViCareInvalidConfigurationError, PyViCareInvalidCredentialsError) as err:
         raise ConfigEntryAuthFailed("Authentication failed") from err
 
+    for device in hass.data[DOMAIN][entry.entry_id][DEVICE_LIST]:
+        # Migration can be removed in 2025.4.0
+        await async_migrate_devices(hass, entry, device)
+        # Migration can be removed in 2025.4.0
+        await async_migrate_entities(hass, entry, device)
+
     await hass.config_entries.async_forward_entry_setups(entry, PLATFORMS)
 
     return True
@@ -109,6 +117,72 @@ async def async_unload_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
     return unload_ok
 
 
+async def async_migrate_devices(
+    hass: HomeAssistant, entry: ConfigEntry, device: ViCareDevice
+) -> None:
+    """Migrate old entry."""
+    registry = dr.async_get(hass)
+
+    gateway_serial: str = device.config.getConfig().serial
+    device_serial: str = device.api.getSerial()
+
+    old_identifier = gateway_serial
+    new_identifier = f"{gateway_serial}_{device_serial}"
+
+    # Migrate devices
+    for device_entry in dr.async_entries_for_config_entry(registry, entry.entry_id):
+        if device_entry.identifiers == {(DOMAIN, old_identifier)}:
+            _LOGGER.debug("Migrating device %s", device_entry.name)
+            registry.async_update_device(
+                device_entry.id,
+                serial_number=device_serial,
+                new_identifiers={(DOMAIN, new_identifier)},
+            )
+
+
+async def async_migrate_entities(
+    hass: HomeAssistant, entry: ConfigEntry, device: ViCareDevice
+) -> None:
+    """Migrate old entry."""
+    gateway_serial: str = device.config.getConfig().serial
+    device_serial: str = device.api.getSerial()
+    new_identifier = f"{gateway_serial}_{device_serial}"
+
+    @callback
+    def _update_unique_id(
+        entity_entry: er.RegistryEntry,
+    ) -> dict[str, str] | None:
+        """Update unique ID of entity entry."""
+        if not entity_entry.unique_id.startswith(gateway_serial):
+            # belongs to other device/gateway
+            return None
+        if entity_entry.unique_id.startswith(f"{gateway_serial}_"):
+            # Already correct, nothing to do
+            return None
+
+        unique_id_parts = entity_entry.unique_id.split("-")
+        unique_id_parts[0] = new_identifier
+
+        # convert climate entity unique id from `<device_identifier>-<circuit_no>` to `<device_identifier>-heating-<circuit_no>`
+        if entity_entry.domain == DOMAIN_CLIMATE:
+            unique_id_parts[len(unique_id_parts) - 1] = (
+                f"{entity_entry.translation_key}-{unique_id_parts[len(unique_id_parts)-1]}"
+            )
+
+        entity_new_unique_id = "-".join(unique_id_parts)
+
+        _LOGGER.debug(
+            "Migrating entity %s from %s to new id %s",
+            entity_entry.entity_id,
+            entity_entry.unique_id,
+            entity_new_unique_id,
+        )
+        return {"new_unique_id": entity_new_unique_id}
+
+    # Migrate entities
+    await er.async_migrate_entries(hass, entry.entry_id, _update_unique_id)
+
+
 def get_supported_devices(
     devices: list[PyViCareDeviceConfig],
 ) -> list[PyViCareDeviceConfig]:
diff --git a/homeassistant/components/vicare/climate.py b/homeassistant/components/vicare/climate.py
index 4968e565d0b..410395760ea 100644
--- a/homeassistant/components/vicare/climate.py
+++ b/homeassistant/components/vicare/climate.py
@@ -148,10 +148,10 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
         circuit: PyViCareHeatingCircuit,
     ) -> None:
         """Initialize the climate device."""
-        super().__init__(circuit.id, device_config, device)
-        self._circuit = circuit
+        super().__init__(self._attr_translation_key, device_config, device, circuit)
+        self._device = device
         self._attributes: dict[str, Any] = {}
-        self._attributes["vicare_programs"] = self._circuit.getPrograms()
+        self._attributes["vicare_programs"] = self._api.getPrograms()
         self._attr_preset_modes = [
             preset
             for heating_program in self._attributes["vicare_programs"]
@@ -163,11 +163,11 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
         try:
             _room_temperature = None
             with suppress(PyViCareNotSupportedFeatureError):
-                _room_temperature = self._circuit.getRoomTemperature()
+                _room_temperature = self._api.getRoomTemperature()
 
             _supply_temperature = None
             with suppress(PyViCareNotSupportedFeatureError):
-                _supply_temperature = self._circuit.getSupplyTemperature()
+                _supply_temperature = self._api.getSupplyTemperature()
 
             if _room_temperature is not None:
                 self._attr_current_temperature = _room_temperature
@@ -177,15 +177,13 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
                 self._attr_current_temperature = None
 
             with suppress(PyViCareNotSupportedFeatureError):
-                self._current_program = self._circuit.getActiveProgram()
+                self._current_program = self._api.getActiveProgram()
 
             with suppress(PyViCareNotSupportedFeatureError):
-                self._attr_target_temperature = (
-                    self._circuit.getCurrentDesiredTemperature()
-                )
+                self._attr_target_temperature = self._api.getCurrentDesiredTemperature()
 
             with suppress(PyViCareNotSupportedFeatureError):
-                self._current_mode = self._circuit.getActiveMode()
+                self._current_mode = self._api.getActiveMode()
 
             # Update the generic device attributes
             self._attributes = {
@@ -196,25 +194,25 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
 
             with suppress(PyViCareNotSupportedFeatureError):
                 self._attributes["heating_curve_slope"] = (
-                    self._circuit.getHeatingCurveSlope()
+                    self._api.getHeatingCurveSlope()
                 )
 
             with suppress(PyViCareNotSupportedFeatureError):
                 self._attributes["heating_curve_shift"] = (
-                    self._circuit.getHeatingCurveShift()
+                    self._api.getHeatingCurveShift()
                 )
 
             with suppress(PyViCareNotSupportedFeatureError):
-                self._attributes["vicare_modes"] = self._circuit.getModes()
+                self._attributes["vicare_modes"] = self._api.getModes()
 
             self._current_action = False
             # Update the specific device attributes
             with suppress(PyViCareNotSupportedFeatureError):
-                for burner in get_burners(self._api):
+                for burner in get_burners(self._device):
                     self._current_action = self._current_action or burner.getActive()
 
             with suppress(PyViCareNotSupportedFeatureError):
-                for compressor in get_compressors(self._api):
+                for compressor in get_compressors(self._device):
                     self._current_action = (
                         self._current_action or compressor.getActive()
                     )
@@ -245,9 +243,9 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
             raise ValueError(f"Cannot set invalid hvac mode: {hvac_mode}")
 
         _LOGGER.debug("Setting hvac mode to %s / %s", hvac_mode, vicare_mode)
-        self._circuit.setMode(vicare_mode)
+        self._api.setMode(vicare_mode)
 
-    def vicare_mode_from_hvac_mode(self, hvac_mode):
+    def vicare_mode_from_hvac_mode(self, hvac_mode) -> str | None:
         """Return the corresponding vicare mode for an hvac_mode."""
         if "vicare_modes" not in self._attributes:
             return None
@@ -283,7 +281,7 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
     def set_temperature(self, **kwargs: Any) -> None:
         """Set new target temperatures."""
         if (temp := kwargs.get(ATTR_TEMPERATURE)) is not None:
-            self._circuit.setProgramTemperature(self._current_program, temp)
+            self._api.setProgramTemperature(self._current_program, temp)
             self._attr_target_temperature = temp
 
     @property
@@ -312,7 +310,7 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
         ):
             _LOGGER.debug("deactivating %s", self._current_program)
             try:
-                self._circuit.deactivateProgram(self._current_program)
+                self._api.deactivateProgram(self._current_program)
             except PyViCareCommandError as err:
                 raise ServiceValidationError(
                     translation_domain=DOMAIN,
@@ -326,7 +324,7 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
         if target_program in CHANGABLE_HEATING_PROGRAMS:
             _LOGGER.debug("activating %s", target_program)
             try:
-                self._circuit.activateProgram(target_program)
+                self._api.activateProgram(target_program)
             except PyViCareCommandError as err:
                 raise ServiceValidationError(
                     translation_domain=DOMAIN,
@@ -341,9 +339,9 @@ class ViCareClimate(ViCareEntity, ClimateEntity):
         """Show Device Attributes."""
         return self._attributes
 
-    def set_vicare_mode(self, vicare_mode):
+    def set_vicare_mode(self, vicare_mode) -> None:
         """Service function to set vicare modes directly."""
         if vicare_mode not in self._attributes["vicare_modes"]:
             raise ValueError(f"Cannot set invalid vicare mode: {vicare_mode}.")
 
-        self._circuit.setMode(vicare_mode)
+        self._api.setMode(vicare_mode)
diff --git a/homeassistant/components/vicare/entity.py b/homeassistant/components/vicare/entity.py
index eef114b4039..f48243e83e1 100644
--- a/homeassistant/components/vicare/entity.py
+++ b/homeassistant/components/vicare/entity.py
@@ -25,18 +25,20 @@ class ViCareEntity(Entity):
         component: PyViCareHeatingDeviceComponent | None = None,
     ) -> None:
         """Initialize the entity."""
+        gateway_serial = device_config.getConfig().serial
+        device_serial = device.getSerial()
+        identifier = f"{gateway_serial}_{device_serial}"
+
         self._api: PyViCareDevice | PyViCareHeatingDeviceComponent = (
             component if component else device
         )
-
-        self._attr_unique_id = f"{device_config.getConfig().serial}-{unique_id_suffix}"
-        # valid for compressors, circuits, burners (HeatingDeviceWithComponent)
+        self._attr_unique_id = f"{identifier}-{unique_id_suffix}"
         if component:
             self._attr_unique_id += f"-{component.id}"
 
         self._attr_device_info = DeviceInfo(
-            identifiers={(DOMAIN, device_config.getConfig().serial)},
-            serial_number=device.getSerial(),
+            identifiers={(DOMAIN, identifier)},
+            serial_number=device_serial,
             name=device_config.getModel(),
             manufacturer="Viessmann",
             model=device_config.getModel(),
diff --git a/tests/components/vicare/fixtures/ViAir300F.json b/tests/components/vicare/fixtures/ViAir300F.json
index b1ec747e127..090c7a81ddf 100644
--- a/tests/components/vicare/fixtures/ViAir300F.json
+++ b/tests/components/vicare/fixtures/ViAir300F.json
@@ -50,7 +50,7 @@
       "properties": {
         "value": {
           "type": "string",
-          "value": "################"
+          "value": "deviceSerialViAir300F"
         }
       },
       "timestamp": "2024-03-20T01:29:35.549Z",
diff --git a/tests/components/vicare/fixtures/Vitodens300W.json b/tests/components/vicare/fixtures/Vitodens300W.json
index bb86bda981b..d183146e94d 100644
--- a/tests/components/vicare/fixtures/Vitodens300W.json
+++ b/tests/components/vicare/fixtures/Vitodens300W.json
@@ -11,10 +11,10 @@
       "properties": {
         "value": {
           "type": "string",
-          "value": "################"
+          "value": "deviceSerialVitodens300W"
         }
       },
-      "timestamp": "2024-03-20T01:29:35.549Z",
+      "timestamp": "2024-07-30T20:03:40.073Z",
       "uri": "https://api.viessmann.com/iot/v1/features/installations/#######/gateways/################/devices/0/features/device.serial"
     },
     {
diff --git a/tests/components/vicare/snapshots/test_binary_sensor.ambr b/tests/components/vicare/snapshots/test_binary_sensor.ambr
index a03a6150c45..f3e4d4e1c84 100644
--- a/tests/components/vicare/snapshots/test_binary_sensor.ambr
+++ b/tests/components/vicare/snapshots/test_binary_sensor.ambr
@@ -28,7 +28,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'burner',
-    'unique_id': 'gateway0-burner_active-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-burner_active-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -75,7 +75,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'circulation_pump',
-    'unique_id': 'gateway0-circulationpump_active-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-circulationpump_active-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -122,7 +122,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'circulation_pump',
-    'unique_id': 'gateway0-circulationpump_active-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-circulationpump_active-1',
     'unit_of_measurement': None,
   })
 # ---
@@ -169,7 +169,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'domestic_hot_water_charging',
-    'unique_id': 'gateway0-charging_active',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-charging_active',
     'unit_of_measurement': None,
   })
 # ---
@@ -216,7 +216,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'domestic_hot_water_circulation_pump',
-    'unique_id': 'gateway0-dhw_circulationpump_active',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-dhw_circulationpump_active',
     'unit_of_measurement': None,
   })
 # ---
@@ -263,7 +263,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'domestic_hot_water_pump',
-    'unique_id': 'gateway0-dhw_pump_active',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-dhw_pump_active',
     'unit_of_measurement': None,
   })
 # ---
@@ -310,7 +310,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'frost_protection',
-    'unique_id': 'gateway0-frost_protection_active-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-frost_protection_active-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -356,7 +356,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'frost_protection',
-    'unique_id': 'gateway0-frost_protection_active-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-frost_protection_active-1',
     'unit_of_measurement': None,
   })
 # ---
diff --git a/tests/components/vicare/snapshots/test_button.ambr b/tests/components/vicare/snapshots/test_button.ambr
index 01120b8b0d6..9fadc6a983f 100644
--- a/tests/components/vicare/snapshots/test_button.ambr
+++ b/tests/components/vicare/snapshots/test_button.ambr
@@ -28,7 +28,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'activate_onetimecharge',
-    'unique_id': 'gateway0-activate_onetimecharge',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-activate_onetimecharge',
     'unit_of_measurement': None,
   })
 # ---
diff --git a/tests/components/vicare/snapshots/test_climate.ambr b/tests/components/vicare/snapshots/test_climate.ambr
index a01d1c43bea..aea0ea879c2 100644
--- a/tests/components/vicare/snapshots/test_climate.ambr
+++ b/tests/components/vicare/snapshots/test_climate.ambr
@@ -40,7 +40,7 @@
     'previous_unique_id': None,
     'supported_features': <ClimateEntityFeature: 401>,
     'translation_key': 'heating',
-    'unique_id': 'gateway0-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-heating-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -123,7 +123,7 @@
     'previous_unique_id': None,
     'supported_features': <ClimateEntityFeature: 401>,
     'translation_key': 'heating',
-    'unique_id': 'gateway0-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-heating-1',
     'unit_of_measurement': None,
   })
 # ---
diff --git a/tests/components/vicare/snapshots/test_diagnostics.ambr b/tests/components/vicare/snapshots/test_diagnostics.ambr
index 430b2de35ad..120bdf7a333 100644
--- a/tests/components/vicare/snapshots/test_diagnostics.ambr
+++ b/tests/components/vicare/snapshots/test_diagnostics.ambr
@@ -16,10 +16,10 @@
             'properties': dict({
               'value': dict({
                 'type': 'string',
-                'value': '################',
+                'value': 'deviceSerialVitodens300W',
               }),
             }),
-            'timestamp': '2024-03-20T01:29:35.549Z',
+            'timestamp': '2024-07-30T20:03:40.073Z',
             'uri': 'https://api.viessmann.com/iot/v1/features/installations/#######/gateways/################/devices/0/features/device.serial',
           }),
           dict({
diff --git a/tests/components/vicare/snapshots/test_fan.ambr b/tests/components/vicare/snapshots/test_fan.ambr
index 48c8d728569..8ec4bc41d8d 100644
--- a/tests/components/vicare/snapshots/test_fan.ambr
+++ b/tests/components/vicare/snapshots/test_fan.ambr
@@ -35,7 +35,7 @@
     'previous_unique_id': None,
     'supported_features': <FanEntityFeature: 9>,
     'translation_key': 'ventilation',
-    'unique_id': 'gateway0-ventilation',
+    'unique_id': 'gateway0_deviceSerialViAir300F-ventilation',
     'unit_of_measurement': None,
   })
 # ---
diff --git a/tests/components/vicare/snapshots/test_number.ambr b/tests/components/vicare/snapshots/test_number.ambr
index e6e87ce5dc7..5a030fc0213 100644
--- a/tests/components/vicare/snapshots/test_number.ambr
+++ b/tests/components/vicare/snapshots/test_number.ambr
@@ -33,7 +33,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'comfort_temperature',
-    'unique_id': 'gateway0-comfort_temperature-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-comfort_temperature-0',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -90,7 +90,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'comfort_temperature',
-    'unique_id': 'gateway0-comfort_temperature-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-comfort_temperature-1',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -147,7 +147,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'heating_curve_shift',
-    'unique_id': 'gateway0-heating curve shift-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-heating curve shift-0',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -204,7 +204,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'heating_curve_shift',
-    'unique_id': 'gateway0-heating curve shift-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-heating curve shift-1',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -261,7 +261,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'heating_curve_slope',
-    'unique_id': 'gateway0-heating curve slope-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-heating curve slope-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -316,7 +316,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'heating_curve_slope',
-    'unique_id': 'gateway0-heating curve slope-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-heating curve slope-1',
     'unit_of_measurement': None,
   })
 # ---
@@ -371,7 +371,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'normal_temperature',
-    'unique_id': 'gateway0-normal_temperature-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-normal_temperature-0',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -428,7 +428,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'normal_temperature',
-    'unique_id': 'gateway0-normal_temperature-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-normal_temperature-1',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -485,7 +485,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'reduced_temperature',
-    'unique_id': 'gateway0-reduced_temperature-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-reduced_temperature-0',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -542,7 +542,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'reduced_temperature',
-    'unique_id': 'gateway0-reduced_temperature-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-reduced_temperature-1',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -599,7 +599,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'dhw_temperature',
-    'unique_id': 'gateway0-dhw_temperature',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-dhw_temperature',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
diff --git a/tests/components/vicare/snapshots/test_sensor.ambr b/tests/components/vicare/snapshots/test_sensor.ambr
index 7bbac75bedc..43e5b713293 100644
--- a/tests/components/vicare/snapshots/test_sensor.ambr
+++ b/tests/components/vicare/snapshots/test_sensor.ambr
@@ -30,7 +30,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'boiler_temperature',
-    'unique_id': 'gateway0-boiler_temperature',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-boiler_temperature',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -81,7 +81,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'burner_hours',
-    'unique_id': 'gateway0-burner_hours-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-burner_hours-0',
     'unit_of_measurement': <UnitOfTime.HOURS: 'h'>,
   })
 # ---
@@ -131,7 +131,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'burner_modulation',
-    'unique_id': 'gateway0-burner_modulation-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-burner_modulation-0',
     'unit_of_measurement': '%',
   })
 # ---
@@ -181,7 +181,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'burner_starts',
-    'unique_id': 'gateway0-burner_starts-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-burner_starts-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -230,7 +230,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'hotwater_gas_consumption_heating_this_month',
-    'unique_id': 'gateway0-hotwater_gas_consumption_heating_this_month',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-hotwater_gas_consumption_heating_this_month',
     'unit_of_measurement': None,
   })
 # ---
@@ -279,7 +279,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'hotwater_gas_consumption_heating_this_week',
-    'unique_id': 'gateway0-hotwater_gas_consumption_heating_this_week',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-hotwater_gas_consumption_heating_this_week',
     'unit_of_measurement': None,
   })
 # ---
@@ -328,7 +328,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'hotwater_gas_consumption_heating_this_year',
-    'unique_id': 'gateway0-hotwater_gas_consumption_heating_this_year',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-hotwater_gas_consumption_heating_this_year',
     'unit_of_measurement': None,
   })
 # ---
@@ -377,7 +377,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'hotwater_gas_consumption_today',
-    'unique_id': 'gateway0-hotwater_gas_consumption_today',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-hotwater_gas_consumption_today',
     'unit_of_measurement': None,
   })
 # ---
@@ -426,7 +426,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'hotwater_max_temperature',
-    'unique_id': 'gateway0-hotwater_max_temperature',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-hotwater_max_temperature',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -477,7 +477,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'hotwater_min_temperature',
-    'unique_id': 'gateway0-hotwater_min_temperature',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-hotwater_min_temperature',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -528,7 +528,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'power consumption this month',
-    'unique_id': 'gateway0-power consumption this month',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-power consumption this month',
     'unit_of_measurement': <UnitOfEnergy.KILO_WATT_HOUR: 'kWh'>,
   })
 # ---
@@ -579,7 +579,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'power_consumption_this_year',
-    'unique_id': 'gateway0-power consumption this year',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-power consumption this year',
     'unit_of_measurement': <UnitOfEnergy.KILO_WATT_HOUR: 'kWh'>,
   })
 # ---
@@ -630,7 +630,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'power_consumption_today',
-    'unique_id': 'gateway0-power consumption today',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-power consumption today',
     'unit_of_measurement': <UnitOfEnergy.KILO_WATT_HOUR: 'kWh'>,
   })
 # ---
@@ -681,7 +681,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'gas_consumption_heating_this_month',
-    'unique_id': 'gateway0-gas_consumption_heating_this_month',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-gas_consumption_heating_this_month',
     'unit_of_measurement': None,
   })
 # ---
@@ -730,7 +730,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'gas_consumption_heating_this_week',
-    'unique_id': 'gateway0-gas_consumption_heating_this_week',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-gas_consumption_heating_this_week',
     'unit_of_measurement': None,
   })
 # ---
@@ -779,7 +779,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'gas_consumption_heating_this_year',
-    'unique_id': 'gateway0-gas_consumption_heating_this_year',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-gas_consumption_heating_this_year',
     'unit_of_measurement': None,
   })
 # ---
@@ -828,7 +828,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'gas_consumption_heating_today',
-    'unique_id': 'gateway0-gas_consumption_heating_today',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-gas_consumption_heating_today',
     'unit_of_measurement': None,
   })
 # ---
@@ -877,7 +877,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'outside_temperature',
-    'unique_id': 'gateway0-outside_temperature',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-outside_temperature',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -928,7 +928,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'power_consumption_this_week',
-    'unique_id': 'gateway0-power consumption this week',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-power consumption this week',
     'unit_of_measurement': <UnitOfEnergy.KILO_WATT_HOUR: 'kWh'>,
   })
 # ---
@@ -979,7 +979,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'supply_temperature',
-    'unique_id': 'gateway0-supply_temperature-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-supply_temperature-0',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
@@ -1030,7 +1030,7 @@
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'supply_temperature',
-    'unique_id': 'gateway0-supply_temperature-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-supply_temperature-1',
     'unit_of_measurement': <UnitOfTemperature.CELSIUS: '°C'>,
   })
 # ---
diff --git a/tests/components/vicare/snapshots/test_water_heater.ambr b/tests/components/vicare/snapshots/test_water_heater.ambr
index 5ab4fcc78bd..bca04b1bbfa 100644
--- a/tests/components/vicare/snapshots/test_water_heater.ambr
+++ b/tests/components/vicare/snapshots/test_water_heater.ambr
@@ -31,7 +31,7 @@
     'previous_unique_id': None,
     'supported_features': <WaterHeaterEntityFeature: 1>,
     'translation_key': 'domestic_hot_water',
-    'unique_id': 'gateway0-0',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-0',
     'unit_of_measurement': None,
   })
 # ---
@@ -87,7 +87,7 @@
     'previous_unique_id': None,
     'supported_features': <WaterHeaterEntityFeature: 1>,
     'translation_key': 'domestic_hot_water',
-    'unique_id': 'gateway0-1',
+    'unique_id': 'gateway0_deviceSerialVitodens300W-1',
     'unit_of_measurement': None,
   })
 # ---
diff --git a/tests/components/vicare/test_init.py b/tests/components/vicare/test_init.py
new file mode 100644
index 00000000000..fea7b5985f1
--- /dev/null
+++ b/tests/components/vicare/test_init.py
@@ -0,0 +1,99 @@
+"""Test ViCare migration."""
+
+from unittest.mock import patch
+
+from homeassistant.components.vicare.const import DOMAIN
+from homeassistant.const import Platform
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers import device_registry as dr, entity_registry as er
+
+from . import MODULE
+from .conftest import Fixture, MockPyViCare
+
+from tests.common import MockConfigEntry
+
+
+# Device migration test can be removed in 2025.4.0
+async def test_device_migration(
+    hass: HomeAssistant,
+    device_registry: dr.DeviceRegistry,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test that the device registry is updated correctly."""
+    fixtures: list[Fixture] = [Fixture({"type:boiler"}, "vicare/Vitodens300W.json")]
+    with (
+        patch(f"{MODULE}.vicare_login", return_value=MockPyViCare(fixtures)),
+        patch(f"{MODULE}.PLATFORMS", [Platform.CLIMATE]),
+    ):
+        mock_config_entry.add_to_hass(hass)
+
+        device_registry.async_get_or_create(
+            config_entry_id=mock_config_entry.entry_id,
+            identifiers={
+                (DOMAIN, "gateway0"),
+            },
+        )
+
+        await hass.config_entries.async_setup(mock_config_entry.entry_id)
+
+        await hass.async_block_till_done()
+
+    assert device_registry.async_get_device(identifiers={(DOMAIN, "gateway0")}) is None
+
+    assert (
+        device_registry.async_get_device(
+            identifiers={(DOMAIN, "gateway0_deviceSerialVitodens300W")}
+        )
+        is not None
+    )
+
+
+# Entity migration test can be removed in 2025.4.0
+async def test_climate_entity_migration(
+    hass: HomeAssistant,
+    entity_registry: er.EntityRegistry,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test that the climate entity unique_id gets migrated correctly."""
+    fixtures: list[Fixture] = [Fixture({"type:boiler"}, "vicare/Vitodens300W.json")]
+    with (
+        patch(f"{MODULE}.vicare_login", return_value=MockPyViCare(fixtures)),
+        patch(f"{MODULE}.PLATFORMS", [Platform.CLIMATE]),
+    ):
+        mock_config_entry.add_to_hass(hass)
+
+        entry1 = entity_registry.async_get_or_create(
+            domain=Platform.CLIMATE,
+            platform=DOMAIN,
+            config_entry=mock_config_entry,
+            unique_id="gateway0-0",
+            translation_key="heating",
+        )
+        entry2 = entity_registry.async_get_or_create(
+            domain=Platform.CLIMATE,
+            platform=DOMAIN,
+            config_entry=mock_config_entry,
+            unique_id="gateway0_deviceSerialVitodens300W-heating-1",
+            translation_key="heating",
+        )
+        entry3 = entity_registry.async_get_or_create(
+            domain=Platform.CLIMATE,
+            platform=DOMAIN,
+            config_entry=mock_config_entry,
+            unique_id="gateway1-0",
+            translation_key="heating",
+        )
+
+        await hass.config_entries.async_setup(mock_config_entry.entry_id)
+
+        await hass.async_block_till_done()
+
+    assert (
+        entity_registry.async_get(entry1.entity_id).unique_id
+        == "gateway0_deviceSerialVitodens300W-heating-0"
+    )
+    assert (
+        entity_registry.async_get(entry2.entity_id).unique_id
+        == "gateway0_deviceSerialVitodens300W-heating-1"
+    )
+    assert entity_registry.async_get(entry3.entity_id).unique_id == "gateway1-0"