diff --git a/party.py b/party.py
index 5dda938dc9..b633dd2d9b 100644
--- a/party.py
+++ b/party.py
@@ -56,6 +56,9 @@ class Party(ModelSQL, ModelView):
                 'receivable_today', 'payable_today'):
             raise Exception('Bad argument')
 
+        if not ids:
+            return {}
+
         for i in ids:
             res[i] = Decimal('0.0')