diff --git a/src/json.hpp b/src/json.hpp
index 5bb8b31a32..5e352c8f08 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -12058,7 +12058,7 @@ class basic_json
 
         // passed iterators must belong to objects
         if (JSON_UNLIKELY(not first.m_object->is_object()
-                          or not first.m_object->is_object()))
+                          or not last.m_object->is_object()))
         {
             JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects"));
         }