diff --git a/addons/mass_mailing/wizard/mail_compose_message.py b/addons/mass_mailing/wizard/mail_compose_message.py
index 6c1fc81280e0b..030ba1f7320f5 100644
--- a/addons/mass_mailing/wizard/mail_compose_message.py
+++ b/addons/mass_mailing/wizard/mail_compose_message.py
@@ -62,7 +62,8 @@ def get_mail_values(self, res_ids):
                 if mail_values.get('email_to'):
                     recips = tools.email_split(mail_values['email_to'])
                 else:
-                    recips = tools.email_split(partners_email.get(res_id))
+                    partner_id = (mail_values.get('recipient_ids') or [(False, '')])[0][1]
+                    recips = tools.email_split(partners_email.get(partner_id))
                 mail_to = recips[0].lower() if recips else False
                 if (blacklist and mail_to in blacklist) or (seen_list and mail_to in seen_list):
                     # prevent sending to blocked addresses that were included by mistake