diff --git a/README.md b/README.md
index 6550e49..4566c94 100644
--- a/README.md
+++ b/README.md
@@ -89,7 +89,7 @@ Message size limit in bytes.
 Mailbox size limit in bytes. `0` disables the limit.
 
 ## TLS_SECURITY_LEVEL
-- default: encrypt
+- default: may
 
 One of:
 - none: TLS will not be used.