diff --git a/type/__matrix_synapse/man.rst b/type/__matrix_synapse/man.rst
index c3de79d..c368755 100644
--- a/type/__matrix_synapse/man.rst
+++ b/type/__matrix_synapse/man.rst
@@ -189,6 +189,9 @@ bind-address
   Address used to bind the synapse listeners. Can be specified multiple times.
   Defaults to '::1' and '127.0.0.1'.
 
+saml2-idp-metadata-url
+  HTTP(S) url to SAML2 Identity Provider (IdP), used for Single Sign On (SSO) logic.
+
 extra-setting
   Arbitrary string to be added to the configuration file. Can be specified multiple times.