diff --git a/py/objexcept.c b/py/objexcept.c
index df91c32b1c..d43cf979e6 100644
--- a/py/objexcept.c
+++ b/py/objexcept.c
@@ -553,7 +553,14 @@ bool mp_obj_is_exception_type(mp_obj_t self_in) {
 
 // return true if the given object is an instance of an exception type
 bool mp_obj_is_exception_instance(mp_obj_t self_in) {
-    return mp_obj_is_exception_type(MP_OBJ_FROM_PTR(mp_obj_get_type(self_in)));
+    if (mp_obj_is_native_exception_instance(self_in)) {
+        return true;
+    }
+    if (!mp_obj_is_exception_type(MP_OBJ_FROM_PTR(mp_obj_get_type(self_in)))) {
+        return false;
+    }
+    mp_obj_instance_t *self = MP_OBJ_TO_PTR(self_in);
+    return self->subobj[0] != MP_OBJ_FROM_PTR((void *)&mp_native_base_init_wrapper_obj);
 }
 
 // Return true if exception (type or instance) is a subclass of given
diff --git a/py/runtime.c b/py/runtime.c
index 3fc35c8c2d..d35cf4025f 100644
--- a/py/runtime.c
+++ b/py/runtime.c
@@ -1508,7 +1508,7 @@ mp_obj_t mp_make_raise_obj(mp_obj_t o) {
     }
 
     if (mp_obj_is_exception_instance(o)) {
-        // o is an instance of an exception, so use it as the exception
+        // o is a fully-constructed instance of an exception, so use it as the exception
         return o;
     } else {
         // o cannot be used as an exception, so return a type error (which will be raised by the caller)