diff --git a/logging_utilities/formatters/json_formatter.py b/logging_utilities/formatters/json_formatter.py
index 9469efc..5a67fb4 100644
--- a/logging_utilities/formatters/json_formatter.py
+++ b/logging_utilities/formatters/json_formatter.py
@@ -349,14 +349,14 @@ def format(self, record):
             if not record.exc_text:
                 record.exc_text = self.formatException(record.exc_info)
 
+        if record.stack_info:
+            record.stack_info = self.formatStack(record.stack_info)
+
         message = self.formatMessage(record)
 
         if self.add_always_extra:
             self._add_extra_to_message(extra, message)
 
-        if record.stack_info:
-            message['stack_info'] = self.formatStack(record.stack_info)
-
         # When adding all extras, to avoid crash when a log message adds an extra with a non
         # serializable object, we add a default serializer.
         default = self.kwargs.pop('default', None)
diff --git a/tests/test_json_formatter.py b/tests/test_json_formatter.py
index 91fdba0..f765d36 100644
--- a/tests/test_json_formatter.py
+++ b/tests/test_json_formatter.py
@@ -378,11 +378,8 @@ def test_stack_info(self):
             logger = logging.getLogger('test_formatter')
             self._configure_logger(
                 logger,
-                fmt=dictionary([
-                    ('levelname', 'levelname'),
-                    ('name', 'name'),
-                    ('message', 'message'),
-                ])
+                fmt=dictionary([('levelname', 'levelname'), ('name', 'name'),
+                                ('message', 'message'), ('stack_info', 'stack_info')])
             )
             logger.info('Message with stack info', stack_info=True)
         message = json.loads(ctx.output[0], object_pairs_hook=dictionary)