diff --git a/homeassistant/components/conversation/default_agent.py b/homeassistant/components/conversation/default_agent.py
index aba5aafd378..94af03a9e90 100644
--- a/homeassistant/components/conversation/default_agent.py
+++ b/homeassistant/components/conversation/default_agent.py
@@ -3,6 +3,7 @@ from __future__ import annotations
 
 from dataclasses import dataclass
 import logging
+from pathlib import Path
 import re
 from typing import Any
 
@@ -10,6 +11,7 @@ from hassil.intents import Intents, SlotList, TextSlotList
 from hassil.recognize import recognize
 from hassil.util import merge_dict
 from home_assistant_intents import get_intents
+import yaml
 
 from homeassistant import core, setup
 from homeassistant.helpers import area_registry, entity_registry, intent
@@ -147,6 +149,32 @@ class DefaultAgent(AbstractConversationAgent):
 
                 # Will need to recreate graph
                 intents_changed = True
+                _LOGGER.debug(
+                    "Loaded intents component=%s, language=%s", component, language
+                )
+
+        # Check for custom sentences in <config>/custom_sentences/<language>/
+        if lang_intents is None:
+            # Only load custom sentences once, otherwise they will be re-loaded
+            # when components change.
+            custom_sentences_dir = Path(
+                self.hass.config.path("custom_sentences", language)
+            )
+            if custom_sentences_dir.is_dir():
+                for custom_sentences_path in custom_sentences_dir.rglob("*.yaml"):
+                    with custom_sentences_path.open(
+                        encoding="utf-8"
+                    ) as custom_sentences_file:
+                        # Merge custom sentences
+                        merge_dict(intents_dict, yaml.safe_load(custom_sentences_file))
+
+                    # Will need to recreate graph
+                    intents_changed = True
+                    _LOGGER.debug(
+                        "Loaded custom sentences language=%s, path=%s",
+                        language,
+                        custom_sentences_path,
+                    )
 
         if not intents_dict:
             return None
diff --git a/tests/components/conversation/test_init.py b/tests/components/conversation/test_init.py
index ffb7894cd00..22ea6208214 100644
--- a/tests/components/conversation/test_init.py
+++ b/tests/components/conversation/test_init.py
@@ -12,6 +12,19 @@ from homeassistant.setup import async_setup_component
 from tests.common import async_mock_service
 
 
+class OrderBeerIntentHandler(intent.IntentHandler):
+    """Handle OrderBeer intent."""
+
+    intent_type = "OrderBeer"
+
+    async def async_handle(self, intent_obj: intent.Intent) -> intent.IntentResponse:
+        """Return speech response."""
+        beer_style = intent_obj.slots["beer_style"]["value"]
+        response = intent_obj.create_response()
+        response.async_set_speech(f"You ordered a {beer_style}")
+        return response
+
+
 @pytest.fixture
 async def init_components(hass):
     """Initialize relevant components with empty configs."""
@@ -314,3 +327,43 @@ async def test_ws_api(hass, hass_ws_client, payload):
         },
         "conversation_id": payload.get("conversation_id") or ANY,
     }
+
+
+async def test_custom_sentences(hass, hass_client, hass_admin_user):
+    """Test custom sentences with a custom intent."""
+    assert await async_setup_component(hass, "homeassistant", {})
+    assert await async_setup_component(hass, "conversation", {})
+    assert await async_setup_component(hass, "intent", {})
+
+    # Expecting testing_config/custom_sentences/en/beer.yaml
+    intent.async_register(hass, OrderBeerIntentHandler())
+
+    # Invoke intent via HTTP API
+    client = await hass_client()
+    for beer_style in ("stout", "lager"):
+        resp = await client.post(
+            "/api/conversation/process",
+            json={"text": f"I'd like to order a {beer_style}, please"},
+        )
+        assert resp.status == HTTPStatus.OK
+        data = await resp.json()
+
+        assert data == {
+            "response": {
+                "card": {},
+                "speech": {
+                    "plain": {
+                        "extra_data": None,
+                        "speech": f"You ordered a {beer_style}",
+                    }
+                },
+                "language": hass.config.language,
+                "response_type": "action_done",
+                "data": {
+                    "targets": [],
+                    "success": [],
+                    "failed": [],
+                },
+            },
+            "conversation_id": None,
+        }
diff --git a/tests/testing_config/custom_sentences/en/beer.yaml b/tests/testing_config/custom_sentences/en/beer.yaml
new file mode 100644
index 00000000000..cedaae42ed1
--- /dev/null
+++ b/tests/testing_config/custom_sentences/en/beer.yaml
@@ -0,0 +1,11 @@
+language: "en"
+intents:
+  OrderBeer:
+    data:
+      - sentences:
+          - "I'd like to order a {beer_style} [please]"
+lists:
+  beer_style:
+    values:
+      - "stout"
+      - "lager"