diff --git a/install/debian/9/exim/exim4.conf.template b/install/debian/9/exim/exim4.conf.template
index 12b41e40..e49bbf4e 100644
--- a/install/debian/9/exim/exim4.conf.template
+++ b/install/debian/9/exim/exim4.conf.template
@@ -25,6 +25,9 @@ acl_smtp_rcpt = acl_check_rcpt
 acl_smtp_data = acl_check_data
 acl_smtp_mime = acl_check_mime
 
+recipients_max = 15
+recipients_max_reject = true
+
 .ifdef SPAMASSASSIN
 spamd_address = 127.0.0.1 783
 .endif