diff --git a/mailsrv/assets/postfix/main.cf.part b/mailsrv/assets/postfix/main.cf.part
index 575b134..4e3f23a 100644
--- a/mailsrv/assets/postfix/main.cf.part
+++ b/mailsrv/assets/postfix/main.cf.part
@@ -75,4 +75,4 @@ biff = no
 # fresh installs.
 compatibility_level = 2
 # maximum size allowed for sent messages, in bytes
-message_size_limit = 104857600
+message_size_limit = 33554432