diff --git a/postfix/conf/main.cf b/postfix/conf/main.cf
index 6cd514e8..4b8db9bd 100644
--- a/postfix/conf/main.cf
+++ b/postfix/conf/main.cf
@@ -28,6 +28,9 @@ mydestination =
 # Relayhost if any is configured
 relayhost = {{ RELAYHOST }}
 
+# Recipient delimiter for extended addresses
+recipient_delimiter = +
+
 ###############
 # TLS
 ###############