diff --git a/hamilton/function_modifiers/adapters.py b/hamilton/function_modifiers/adapters.py
index 11133822d..8a80ba50d 100644
--- a/hamilton/function_modifiers/adapters.py
+++ b/hamilton/function_modifiers/adapters.py
@@ -854,8 +854,8 @@ def save_json_data(data: pd.DataFrame, json_path: str = "data/my_saved_data.json
 
     def validate(self, fn: Callable):
         """Validates that the function output is a dict type."""
-        return_annotation = inspect.signature(fn).return_annotation
-        if return_annotation is inspect.Signature.empty:
+        return_annotation = typing.get_type_hints(fn)["return"]
+        if return_annotation is None:
             raise InvalidDecoratorException(
                 f"Function: {fn.__qualname__} must have a return annotation."
             )
diff --git a/tests/function_modifiers/test_adapters.py b/tests/function_modifiers/test_adapters.py
index 06ba57b6b..4904510de 100644
--- a/tests/function_modifiers/test_adapters.py
+++ b/tests/function_modifiers/test_adapters.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import dataclasses
 from collections import Counter
 from typing import Any, Collection, Dict, List, Tuple, Type