diff --git a/src/chronos/base.py b/src/chronos/base.py
index 2bba087..807f91d 100644
--- a/src/chronos/base.py
+++ b/src/chronos/base.py
@@ -348,9 +348,16 @@ class BaseChronosPipeline(metaclass=PipelineRegistry):
         if str(pretrained_model_name_or_path).startswith("s3://"):
             from .boto_utils import cache_model_from_s3
 
-            local_model_path = cache_model_from_s3(
-                str(pretrained_model_name_or_path), force_download=force_s3_download
-            )
+            try:
+                local_model_path = cache_model_from_s3(
+                    str(pretrained_model_name_or_path), force_download=force_s3_download
+                )
+            except ImportError as e:
+                raise ImportError(
+                    "Loading models from s3:// URIs requires boto3. "
+                    "Install the optional dependencies with: "
+                    "pip install 'chronos-forecasting[extras]'"
+                ) from e
             return cls.from_pretrained(local_model_path, *model_args, **kwargs)
 
         from transformers import AutoConfig
diff --git a/src/chronos/boto_utils.py b/src/chronos/boto_utils.py
index d339333..48393d6 100644
--- a/src/chronos/boto_utils.py
+++ b/src/chronos/boto_utils.py
@@ -3,17 +3,19 @@
 
 # Authors: Abdul Fatir Ansari <ansarnd@amazon.com>
 
+from __future__ import annotations
+
 import logging
 import os
 import re
 import warnings
 from pathlib import Path
+from typing import TYPE_CHECKING
 
-import boto3
 import requests  # type: ignore
-from botocore import UNSIGNED
-from botocore.client import Config
-from botocore.exceptions import ClientError, NoCredentialsError
+
+if TYPE_CHECKING:
+    import boto3
 
 logger = logging.getLogger(__name__)
 
@@ -57,6 +59,11 @@ def download_model_files_from_s3(
     force_download: bool = False,
     boto3_session: boto3.Session | None = None,
 ) -> None:
+    import boto3
+    from botocore import UNSIGNED
+    from botocore.client import Config
+    from botocore.exceptions import ClientError, NoCredentialsError
+
     boto3_session = boto3_session or boto3.Session()
     s3_client = boto3_session.client("s3")