diff --git a/roles/matrix-synapse/defaults/main.yml b/roles/matrix-synapse/defaults/main.yml
index f1a3e457..3e3ee121 100644
--- a/roles/matrix-synapse/defaults/main.yml
+++ b/roles/matrix-synapse/defaults/main.yml
@@ -597,7 +597,7 @@ matrix_synapse_room_list_publication_rules:
     room_id: "*"
     action: allow
 
-matrix_synapse_default_room_version: "6"
+matrix_synapse_default_room_version: "9"
 
 # Controls the Synapse `spam_checker` setting.
 #