diff --git a/modules/reitit-ring/src/reitit/ring.cljc b/modules/reitit-ring/src/reitit/ring.cljc
index 2f63dfdc..3585caf8 100644
--- a/modules/reitit-ring/src/reitit/ring.cljc
+++ b/modules/reitit-ring/src/reitit/ring.cljc
@@ -99,6 +99,8 @@
                       :compile compile-result
                       ::default-options-endpoint default-options-endpoint}
                      opts)]
+     (assert (not (contains? opts ::default-options-handler))
+             "Option `::default-options-handler` is deprecated. Use `::default-options-endpoint` instead.")
      (r/router data opts))))
 
 (defn routes