diff --git a/homeassistant/components/ai_task/__init__.py b/homeassistant/components/ai_task/__init__.py
index 5d8082e06b3..2021a92d6e2 100644
--- a/homeassistant/components/ai_task/__init__.py
+++ b/homeassistant/components/ai_task/__init__.py
@@ -3,12 +3,12 @@
 import logging
 
 from homeassistant.config_entries import ConfigEntry
-from homeassistant.core import HomeAssistant
-from homeassistant.helpers import config_validation as cv
+from homeassistant.core import HomeAssistant, callback
+from homeassistant.helpers import config_validation as cv, storage
 from homeassistant.helpers.entity_component import EntityComponent
-from homeassistant.helpers.typing import ConfigType
+from homeassistant.helpers.typing import UNDEFINED, ConfigType, UndefinedType
 
-from .const import DATA_COMPONENT, DOMAIN
+from .const import DATA_COMPONENT, DATA_PREFERENCES, DOMAIN
 from .entity import AITaskEntity
 from .http import async_setup as async_setup_conversation_http
 from .task import GenTextTask, GenTextTaskResult, async_generate_text
@@ -33,6 +33,8 @@ async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
     """Register the process service."""
     entity_component = EntityComponent[AITaskEntity](_LOGGER, DOMAIN, hass)
     hass.data[DATA_COMPONENT] = entity_component
+    hass.data[DATA_PREFERENCES] = AITaskPreferences(hass)
+    await hass.data[DATA_PREFERENCES].async_load()
     async_setup_conversation_http(hass)
     return True
 
@@ -45,3 +47,53 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
 async def async_unload_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
     """Unload a config entry."""
     return await hass.data[DATA_COMPONENT].async_unload_entry(entry)
+
+
+class AITaskPreferences:
+    """AI Task preferences."""
+
+    gen_text_entity_id: str | None = None
+
+    def __init__(self, hass: HomeAssistant) -> None:
+        """Initialize the preferences."""
+        self._store: storage.Store[dict[str, str | None]] = storage.Store(
+            hass, 1, DOMAIN
+        )
+
+    async def async_load(self) -> None:
+        """Load the data from the store."""
+        data = await self._store.async_load()
+        if data is None:
+            return
+        self.gen_text_entity_id = data.get("gen_text_entity_id")
+
+    @callback
+    def async_set_preferences(
+        self,
+        *,
+        gen_text_entity_id: str | None | UndefinedType = UNDEFINED,
+    ) -> None:
+        """Set the preferences."""
+        changed = False
+        for key, value in (("gen_text_entity_id", gen_text_entity_id),):
+            if value is not UNDEFINED:
+                if getattr(self, key) != value:
+                    setattr(self, key, value)
+                    changed = True
+
+        if not changed:
+            return
+
+        self._store.async_delay_save(
+            lambda: {
+                "gen_text_entity_id": self.gen_text_entity_id,
+            },
+            10,
+        )
+
+    @callback
+    def as_dict(self) -> dict[str, str | None]:
+        """Get the current preferences."""
+        return {
+            "gen_text_entity_id": self.gen_text_entity_id,
+        }
diff --git a/homeassistant/components/ai_task/const.py b/homeassistant/components/ai_task/const.py
index 7c5b4e281d2..03809da5f4a 100644
--- a/homeassistant/components/ai_task/const.py
+++ b/homeassistant/components/ai_task/const.py
@@ -9,10 +9,12 @@ from homeassistant.util.hass_dict import HassKey
 if TYPE_CHECKING:
     from homeassistant.helpers.entity_component import EntityComponent
 
+    from . import AITaskPreferences
     from .entity import AITaskEntity
 
 DOMAIN = "ai_task"
 DATA_COMPONENT: HassKey[EntityComponent[AITaskEntity]] = HassKey(DOMAIN)
+DATA_PREFERENCES: HassKey[AITaskPreferences] = HassKey(f"{DOMAIN}_preferences")
 
 DEFAULT_SYSTEM_PROMPT = (
     "You are a Home Assistant expert and help users with their tasks."
diff --git a/homeassistant/components/ai_task/http.py b/homeassistant/components/ai_task/http.py
index 22a603662ee..e82d71a218f 100644
--- a/homeassistant/components/ai_task/http.py
+++ b/homeassistant/components/ai_task/http.py
@@ -7,6 +7,7 @@ import voluptuous as vol
 from homeassistant.components import websocket_api
 from homeassistant.core import HomeAssistant, callback
 
+from .const import DATA_PREFERENCES
 from .task import async_generate_text
 
 
@@ -14,13 +15,15 @@ from .task import async_generate_text
 def async_setup(hass: HomeAssistant) -> None:
     """Set up the HTTP API for the conversation integration."""
     websocket_api.async_register_command(hass, websocket_generate_text)
+    websocket_api.async_register_command(hass, websocket_get_preferences)
+    websocket_api.async_register_command(hass, websocket_set_preferences)
 
 
 @websocket_api.websocket_command(
     {
         vol.Required("type"): "ai_task/generate_text",
         vol.Required("task_name"): str,
-        vol.Required("entity_id"): str,
+        vol.Optional("entity_id"): str,
         vol.Required("instructions"): str,
     }
 )
@@ -34,5 +37,46 @@ async def websocket_generate_text(
     """Run a generate text task."""
     msg.pop("type")
     msg_id = msg.pop("id")
-    result = await async_generate_text(hass=hass, **msg)
+    try:
+        result = await async_generate_text(hass=hass, **msg)
+    except ValueError as err:
+        connection.send_error(msg_id, websocket_api.const.ERR_UNKNOWN_ERROR, str(err))
+        return
     connection.send_result(msg_id, result.as_dict())
+
+
+@websocket_api.websocket_command(
+    {
+        vol.Required("type"): "ai_task/preferences/get",
+    }
+)
+@callback
+def websocket_get_preferences(
+    hass: HomeAssistant,
+    connection: websocket_api.ActiveConnection,
+    msg: dict[str, Any],
+) -> None:
+    """Get AI task preferences."""
+    preferences = hass.data[DATA_PREFERENCES]
+    connection.send_result(msg["id"], preferences.as_dict())
+
+
+@websocket_api.websocket_command(
+    {
+        vol.Required("type"): "ai_task/preferences/set",
+        vol.Optional("gen_text_entity_id"): vol.Any(str, None),
+    }
+)
+@websocket_api.require_admin
+@callback
+def websocket_set_preferences(
+    hass: HomeAssistant,
+    connection: websocket_api.ActiveConnection,
+    msg: dict[str, Any],
+) -> None:
+    """Set AI task preferences."""
+    preferences = hass.data[DATA_PREFERENCES]
+    msg.pop("type")
+    msg_id = msg.pop("id")
+    preferences.async_set_preferences(**msg)
+    connection.send_result(msg_id, preferences.as_dict())
diff --git a/homeassistant/components/ai_task/task.py b/homeassistant/components/ai_task/task.py
index 0a286cb7fcf..e326d83c9d7 100644
--- a/homeassistant/components/ai_task/task.py
+++ b/homeassistant/components/ai_task/task.py
@@ -6,17 +6,23 @@ from dataclasses import dataclass
 
 from homeassistant.core import HomeAssistant
 
-from .const import DATA_COMPONENT
+from .const import DATA_COMPONENT, DATA_PREFERENCES
 
 
 async def async_generate_text(
     hass: HomeAssistant,
     *,
     task_name: str,
-    entity_id: str,
+    entity_id: str | None = None,
     instructions: str,
 ) -> GenTextTaskResult:
     """Run a task in the AI Task integration."""
+    if entity_id is None:
+        entity_id = hass.data[DATA_PREFERENCES].gen_text_entity_id
+
+    if entity_id is None:
+        raise ValueError("No entity_id provided and no preferred entity set")
+
     entity = hass.data[DATA_COMPONENT].get_entity(entity_id)
     if entity is None:
         raise ValueError(f"AI Task entity {entity_id} not found")
diff --git a/tests/components/ai_task/test_http.py b/tests/components/ai_task/test_http.py
index ac3395e84b0..c2e84f86f98 100644
--- a/tests/components/ai_task/test_http.py
+++ b/tests/components/ai_task/test_http.py
@@ -1,5 +1,8 @@
 """Test the HTTP API for AI Task integration."""
 
+import pytest
+
+from homeassistant.components.ai_task import DATA_PREFERENCES
 from homeassistant.const import STATE_UNKNOWN
 from homeassistant.core import HomeAssistant
 
@@ -8,12 +11,21 @@ from .conftest import TEST_ENTITY_ID
 from tests.typing import WebSocketGenerator
 
 
+@pytest.mark.parametrize(
+    "msg_extra",
+    [
+        {},
+        {"entity_id": TEST_ENTITY_ID},
+    ],
+)
 async def test_ws_generate_text(
     hass: HomeAssistant,
     hass_ws_client: WebSocketGenerator,
     init_components: None,
+    msg_extra: dict,
 ) -> None:
     """Test running a generate text task via the WebSocket API."""
+    hass.data[DATA_PREFERENCES].async_set_preferences(gen_text_entity_id=TEST_ENTITY_ID)
     entity = hass.states.get(TEST_ENTITY_ID)
     assert entity is not None
     assert entity.state == STATE_UNKNOWN
@@ -24,9 +36,9 @@ async def test_ws_generate_text(
         {
             "type": "ai_task/generate_text",
             "task_name": "Test Task",
-            "entity_id": TEST_ENTITY_ID,
             "instructions": "Test prompt",
         }
+        | msg_extra
     )
 
     msg = await client.receive_json()
@@ -36,3 +48,82 @@ async def test_ws_generate_text(
 
     entity = hass.states.get(TEST_ENTITY_ID)
     assert entity.state != STATE_UNKNOWN
+
+
+async def test_ws_preferences(
+    hass: HomeAssistant,
+    hass_ws_client: WebSocketGenerator,
+    init_components: None,
+) -> None:
+    """Test preferences via the WebSocket API."""
+    client = await hass_ws_client(hass)
+
+    # Get initial preferences
+    await client.send_json_auto_id({"type": "ai_task/preferences/get"})
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": None,
+    }
+
+    # Set preferences
+    await client.send_json_auto_id(
+        {
+            "type": "ai_task/preferences/set",
+            "gen_text_entity_id": "ai_task.summary_1",
+        }
+    )
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": "ai_task.summary_1",
+    }
+
+    # Get updated preferences
+    await client.send_json_auto_id({"type": "ai_task/preferences/get"})
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": "ai_task.summary_1",
+    }
+
+    # Set only one preference
+    await client.send_json_auto_id(
+        {
+            "type": "ai_task/preferences/set",
+            "gen_text_entity_id": "ai_task.summary_2",
+        }
+    )
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": "ai_task.summary_2",
+    }
+
+    # Get updated preferences
+    await client.send_json_auto_id({"type": "ai_task/preferences/get"})
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": "ai_task.summary_2",
+    }
+
+    # Clear a preference
+    await client.send_json_auto_id(
+        {
+            "type": "ai_task/preferences/set",
+        }
+    )
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": "ai_task.summary_2",
+    }
+
+    # Get updated preferences
+    await client.send_json_auto_id({"type": "ai_task/preferences/get"})
+    msg = await client.receive_json()
+    assert msg["success"]
+    assert msg["result"] == {
+        "gen_text_entity_id": "ai_task.summary_2",
+    }
diff --git a/tests/components/ai_task/test_init.py b/tests/components/ai_task/test_init.py
new file mode 100644
index 00000000000..2498ee2680a
--- /dev/null
+++ b/tests/components/ai_task/test_init.py
@@ -0,0 +1,53 @@
+"""Test initialization of the AI Task component."""
+
+from freezegun.api import FrozenDateTimeFactory
+
+from homeassistant.components.ai_task import AITaskPreferences
+from homeassistant.components.ai_task.const import DATA_PREFERENCES
+from homeassistant.core import HomeAssistant
+
+from tests.common import flush_store
+
+
+async def test_preferences_storage_load(
+    hass: HomeAssistant,
+    init_components: None,
+    freezer: FrozenDateTimeFactory,
+) -> None:
+    """Test that AITaskPreferences are stored and loaded correctly."""
+    preferences = hass.data[DATA_PREFERENCES]
+
+    # Initial state should be None for entity IDs
+    assert preferences.gen_text_entity_id is None
+
+    gen_text_id_1 = "sensor.summary_one"
+
+    preferences.async_set_preferences(
+        gen_text_entity_id=gen_text_id_1,
+    )
+
+    # Verify that current preferences object is updated
+    assert preferences.gen_text_entity_id == gen_text_id_1
+
+    await flush_store(preferences._store)
+
+    # Create a new preferences instance to test loading from store
+    new_preferences_instance = AITaskPreferences(hass)
+    await new_preferences_instance.async_load()
+
+    assert new_preferences_instance.gen_text_entity_id == gen_text_id_1
+
+    # Test updating one preference and setting another to None
+    gen_text_id_2 = "sensor.summary_two"
+    preferences.async_set_preferences(gen_text_entity_id=gen_text_id_2)
+
+    # Verify that current preferences object is updated
+    assert preferences.gen_text_entity_id == gen_text_id_2
+
+    await flush_store(preferences._store)
+
+    # Create another new preferences instance to confirm persistence of the update
+    another_new_preferences_instance = AITaskPreferences(hass)
+    await another_new_preferences_instance.async_load()
+
+    assert another_new_preferences_instance.gen_text_entity_id == gen_text_id_2
diff --git a/tests/components/ai_task/test_task.py b/tests/components/ai_task/test_task.py
index 56a1ff20a6a..7a9d01e867d 100644
--- a/tests/components/ai_task/test_task.py
+++ b/tests/components/ai_task/test_task.py
@@ -4,14 +4,56 @@ from freezegun import freeze_time
 import pytest
 from syrupy.assertion import SnapshotAssertion
 
-from homeassistant.components.ai_task import async_generate_text
+from homeassistant.components.ai_task import DATA_PREFERENCES, async_generate_text
 from homeassistant.components.conversation import async_get_chat_log
+from homeassistant.const import STATE_UNKNOWN
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers import chat_session
 
 from .conftest import TEST_ENTITY_ID
 
 
+async def test_run_task_preferred_entity(
+    hass: HomeAssistant,
+    init_components: None,
+) -> None:
+    """Test running a task with an unknown entity."""
+    preferences = hass.data[DATA_PREFERENCES]
+
+    with pytest.raises(
+        ValueError, match="No entity_id provided and no preferred entity set"
+    ):
+        await async_generate_text(
+            hass,
+            task_name="Test Task",
+            instructions="Test prompt",
+        )
+
+    preferences.async_set_preferences(gen_text_entity_id="ai_task.unknown")
+
+    with pytest.raises(ValueError, match="AI Task entity ai_task.unknown not found"):
+        await async_generate_text(
+            hass,
+            task_name="Test Task",
+            instructions="Test prompt",
+        )
+
+    preferences.async_set_preferences(gen_text_entity_id=TEST_ENTITY_ID)
+    state = hass.states.get(TEST_ENTITY_ID)
+    assert state is not None
+    assert state.state == STATE_UNKNOWN
+
+    result = await async_generate_text(
+        hass,
+        task_name="Test Task",
+        instructions="Test prompt",
+    )
+    assert result.result == "Mock result"
+    state = hass.states.get(TEST_ENTITY_ID)
+    assert state is not None
+    assert state.state != STATE_UNKNOWN
+
+
 async def test_run_text_task_unknown_entity(
     hass: HomeAssistant,
     init_components: None,