diff --git a/unrouted_handler.go b/unrouted_handler.go
index 3c0275b..e8a52e2 100644
--- a/unrouted_handler.go
+++ b/unrouted_handler.go
@@ -119,13 +119,16 @@ func NewUnroutedHandler(config Config) (*UnroutedHandler, error) {
 	}
 
 	// Only promote extesions using the Tus-Extension header which are implemented
-	extensions := "creation,creation-with-upload,creation-defer-length"
+	extensions := "creation,creation-with-upload"
 	if config.StoreComposer.UsesTerminater {
 		extensions += ",termination"
 	}
 	if config.StoreComposer.UsesConcater {
 		extensions += ",concatenation"
 	}
+	if config.StoreComposer.UsesLengthDeferrer {
+		extensions += ",creation-defer-length"
+	}
 
 	handler := &UnroutedHandler{
 		config:            config,