diff --git a/pydruid/query.py b/pydruid/query.py
index cb20cf2..f95209d 100644
--- a/pydruid/query.py
+++ b/pydruid/query.py
@@ -394,6 +394,7 @@ def groupby(self, args):
             "dimensions",
             "limit_spec",
             "virtualColumns",
+            "subtotalsSpec"
         ]
         self.validate_query(query_type, valid_parts, args)
         return self.build_query(query_type, args)