diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6f5014110..7aade22d1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -87,12 +87,21 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
-- Updated `SarvamTTSService` to use WebSocket streaming for real-time audio 
-  generation with multiple Indian languages, with HTTP support still available 
+- Added support to `AWSBedrockLLMService` for setting authentication
+  credentials through environment variables.
+
+- Updated `SarvamTTSService` to use WebSocket streaming for real-time audio
+  generation with multiple Indian languages, with HTTP support still available
   via `SarvamHttpTTSService`.
 
 ### Fixed
 
+- Fixed a missing import in `SentryMetrics`.
+
+- Fixed `AWSPollyTTSService` to support AWS credential provider chain (IAM
+  roles, IRSA, instance profiles) instead of requiring explicit environment
+  variables.
+
 - Fixed a `CartesiaTTSService` issue that was causing the application to hang
   after Cartesia's 5 minutes timed out.
 
@@ -145,8 +154,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Deprecated
 
-- `FrameProcessor.wait_for_task()` is deprecated. Use `await task` or `await
-asyncio.wait_for(task, timeout)` instead.
+- `FrameProcessor.wait_for_task()` is deprecated. Use `await task` or
+  `await asyncio.wait_for(task, timeout)` instead.
 
 ### Removed
 
diff --git a/src/pipecat/services/aws/llm.py b/src/pipecat/services/aws/llm.py
index 6e109c4c1..7b9691b04 100644
--- a/src/pipecat/services/aws/llm.py
+++ b/src/pipecat/services/aws/llm.py
@@ -16,6 +16,7 @@ import base64
 import copy
 import io
 import json
+import os
 import re
 from dataclasses import dataclass
 from typing import Any, Dict, List, Optional
@@ -761,10 +762,10 @@ class AWSBedrockLLMService(LLMService):
 
         # Store AWS session parameters for creating client in async context
         self._aws_params = {
-            "aws_access_key_id": aws_access_key,
-            "aws_secret_access_key": aws_secret_key,
-            "aws_session_token": aws_session_token,
-            "region_name": aws_region,
+            "aws_access_key_id": aws_access_key or os.getenv("AWS_ACCESS_KEY_ID"),
+            "aws_secret_access_key": aws_secret_key or os.getenv("AWS_SECRET_ACCESS_KEY"),
+            "aws_session_token": aws_session_token or os.getenv("AWS_SESSION_TOKEN"),
+            "region_name": aws_region or os.getenv("AWS_REGION", "us-east-1"),
             "config": client_config,
         }
 
diff --git a/src/pipecat/services/aws/tts.py b/src/pipecat/services/aws/tts.py
index 88f0a8fdd..805d733e8 100644
--- a/src/pipecat/services/aws/tts.py
+++ b/src/pipecat/services/aws/tts.py
@@ -185,16 +185,6 @@ class AWSPollyTTSService(TTSService):
             "region_name": region or os.getenv("AWS_REGION", "us-east-1"),
         }
 
-        # Validate that we have the required credentials
-        if (
-            not self._aws_params["aws_access_key_id"]
-            or not self._aws_params["aws_secret_access_key"]
-        ):
-            raise ValueError(
-                "AWS credentials not found. Please provide them either through constructor parameters "
-                "or set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables."
-            )
-
         self._aws_session = aioboto3.Session()
         self._settings = {
             "engine": params.engine,