diff --git a/triagebot.toml b/triagebot.toml
index 5290efd2c..2c690267a 100644
--- a/triagebot.toml
+++ b/triagebot.toml
@@ -1,3 +1,6 @@
+[assign]
+warn_non_default_branch = true
+
 [relabel]
 allow-unauthenticated = [
     "S-waiting-on-review",