diff --git a/changelog/3457.changed.md b/changelog/3457.changed.md
new file mode 100644
index 000000000..d0d82ad2d
--- /dev/null
+++ b/changelog/3457.changed.md
@@ -0,0 +1 @@
+- Changed tool result JSON serialization to use `ensure_ascii=False`, preserving UTF-8 characters instead of escaping them. This reduces context size and token usage for non-English languages.
diff --git a/src/pipecat/services/anthropic/llm.py b/src/pipecat/services/anthropic/llm.py
index fcaed1dfe..2f375df82 100644
--- a/src/pipecat/services/anthropic/llm.py
+++ b/src/pipecat/services/anthropic/llm.py
@@ -1246,7 +1246,7 @@ class AnthropicAssistantContextAggregator(LLMAssistantContextAggregator):
             frame: Frame containing function call result.
         """
         if frame.result:
-            result = json.dumps(frame.result)
+            result = json.dumps(frame.result, ensure_ascii=False)
             await self._update_function_call_result(frame.function_name, frame.tool_call_id, result)
         else:
             await self._update_function_call_result(
diff --git a/src/pipecat/services/aws/llm.py b/src/pipecat/services/aws/llm.py
index 59859abf7..92049dffb 100644
--- a/src/pipecat/services/aws/llm.py
+++ b/src/pipecat/services/aws/llm.py
@@ -691,7 +691,7 @@ class AWSBedrockAssistantContextAggregator(LLMAssistantContextAggregator):
             frame: The function call result frame to handle.
         """
         if frame.result:
-            result = json.dumps(frame.result)
+            result = json.dumps(frame.result, ensure_ascii=False)
             await self._update_function_call_result(frame.function_name, frame.tool_call_id, result)
         else:
             await self._update_function_call_result(
diff --git a/src/pipecat/services/aws/nova_sonic/llm.py b/src/pipecat/services/aws/nova_sonic/llm.py
index b1f56dbbd..0947ba1d7 100644
--- a/src/pipecat/services/aws/nova_sonic/llm.py
+++ b/src/pipecat/services/aws/nova_sonic/llm.py
@@ -1044,7 +1044,9 @@ class AWSNovaSonicLLMService(LLMService):
                     "toolResult": {
                         "promptName": self._prompt_name,
                         "contentName": content_name,
-                        "content": json.dumps(result) if isinstance(result, dict) else result,
+                        "content": json.dumps(result, ensure_ascii=False)
+                        if isinstance(result, dict)
+                        else result,
                     }
                 }
             }
diff --git a/src/pipecat/services/google/llm.py b/src/pipecat/services/google/llm.py
index 698b9f97f..26ad46311 100644
--- a/src/pipecat/services/google/llm.py
+++ b/src/pipecat/services/google/llm.py
@@ -200,7 +200,9 @@ class GoogleAssistantContextAggregator(OpenAIAssistantContextAggregator):
             if message.role == "user":
                 for part in message.parts:
                     if part.function_response and part.function_response.id == tool_call_id:
-                        part.function_response.response = {"value": json.dumps(result)}
+                        part.function_response.response = {
+                            "value": json.dumps(result, ensure_ascii=False)
+                        }
 
 
 @dataclass
diff --git a/src/pipecat/services/grok/realtime/llm.py b/src/pipecat/services/grok/realtime/llm.py
index bfa192aad..6e37d21d2 100644
--- a/src/pipecat/services/grok/realtime/llm.py
+++ b/src/pipecat/services/grok/realtime/llm.py
@@ -939,7 +939,7 @@ class GrokRealtimeLLMService(LLMService):
         item = events.ConversationItem(
             type="function_call_output",
             call_id=tool_call_id,
-            output=json.dumps(result),
+            output=json.dumps(result, ensure_ascii=False),
         )
         await self.send_client_event(events.ConversationItemCreateEvent(item=item))
 
diff --git a/src/pipecat/services/openai/llm.py b/src/pipecat/services/openai/llm.py
index abb3e7eec..553733922 100644
--- a/src/pipecat/services/openai/llm.py
+++ b/src/pipecat/services/openai/llm.py
@@ -255,7 +255,7 @@ class OpenAIAssistantContextAggregator(LLMAssistantContextAggregator):
             frame: Frame containing the function call result.
         """
         if frame.result:
-            result = json.dumps(frame.result)
+            result = json.dumps(frame.result, ensure_ascii=False)
             await self._update_function_call_result(frame.function_name, frame.tool_call_id, result)
         else:
             await self._update_function_call_result(
diff --git a/src/pipecat/services/openai/realtime/llm.py b/src/pipecat/services/openai/realtime/llm.py
index faaa19884..bd31369ae 100644
--- a/src/pipecat/services/openai/realtime/llm.py
+++ b/src/pipecat/services/openai/realtime/llm.py
@@ -1128,7 +1128,7 @@ class OpenAIRealtimeLLMService(LLMService):
         item = events.ConversationItem(
             type="function_call_output",
             call_id=tool_call_id,
-            output=json.dumps(result),
+            output=json.dumps(result, ensure_ascii=False),
         )
         await self.send_client_event(events.ConversationItemCreateEvent(item=item))
 
diff --git a/src/pipecat/services/openai_realtime_beta/openai.py b/src/pipecat/services/openai_realtime_beta/openai.py
index 0a6315986..0d20039b1 100644
--- a/src/pipecat/services/openai_realtime_beta/openai.py
+++ b/src/pipecat/services/openai_realtime_beta/openai.py
@@ -441,7 +441,7 @@ class OpenAIRealtimeBetaLLMService(LLMService):
         item = events.ConversationItem(
             type="function_call_output",
             call_id=frame.tool_call_id,
-            output=json.dumps(frame.result),
+            output=json.dumps(frame.result, ensure_ascii=False),
         )
         await self.send_client_event(events.ConversationItemCreateEvent(item=item))