diff --git a/src/graphql/execution/execute.py b/src/graphql/execution/execute.py
index 7b2837de..eda552a3 100644
--- a/src/graphql/execution/execute.py
+++ b/src/graphql/execution/execute.py
@@ -131,9 +131,12 @@ def __iter__(self) -> Iterable[Any]:
     @property
     def formatted(self) -> Dict[str, Any]:
         """Get execution result formatted according to the specification."""
+        formatted_errors = ([err.formatted for err in self.errors]
+                            if self.errors is not None
+                            else None)
         if self.extensions is None:
-            return dict(data=self.data, errors=self.errors)
-        return dict(data=self.data, errors=self.errors, extensions=self.extensions)
+            return dict(data=self.data, errors=formatted_errors)
+        return dict(data=self.data, errors=formatted_errors, extensions=self.extensions)
 
     def __eq__(self, other: Any) -> bool:
         if isinstance(other, dict):
diff --git a/tests/execution/test_execution_result.py b/tests/execution/test_execution_result.py
index 71ab9fe8..e6c1d3e4 100644
--- a/tests/execution/test_execution_result.py
+++ b/tests/execution/test_execution_result.py
@@ -34,11 +34,11 @@ def prints_a_representation():
 
     def formats_properly():
         res = ExecutionResult(data, errors)
-        assert res.formatted == {"data": data, "errors": errors}
+        assert res.formatted == {"data": data, "errors": [{'message': 'Some error', 'locations': None, 'path': None}]}
         res = ExecutionResult(data, errors, extensions)
         assert res.formatted == {
             "data": data,
-            "errors": errors,
+            "errors": [{'message': 'Some error', 'locations': None, 'path': None}],
             "extensions": extensions,
         }