diff --git a/exercise/api/csv/views.py b/exercise/api/csv/views.py
index 1b47037e1..6d6dd5eba 100644
--- a/exercise/api/csv/views.py
+++ b/exercise/api/csv/views.py
@@ -158,6 +158,8 @@ def submitted_field(submission, name):
         response = Response(data)
         if isinstance(getattr(request, 'accepted_renderer'), CSVRenderer):
             response['Content-Disposition'] = 'attachment; filename="submissions.csv"'
+        else:
+            response['Content-Disposition'] = 'attachment; filename="submissions.json"'
         return response
 
     def get_renderer_context(self):