diff --git a/py/objtuple.c b/py/objtuple.c
index fa5309aae..eaf0e37f4 100644
--- a/py/objtuple.c
+++ b/py/objtuple.c
@@ -138,7 +138,8 @@ mp_obj_t mp_obj_tuple_unary_op(mp_uint_t op, mp_obj_t self_in) {
 mp_obj_t mp_obj_tuple_binary_op(mp_uint_t op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_tuple_t *o = MP_OBJ_TO_PTR(lhs);
     switch (op) {
-        case MP_BINARY_OP_ADD: {
+        case MP_BINARY_OP_ADD:
+        case MP_BINARY_OP_INPLACE_ADD: {
             if (!mp_obj_is_subclass_fast(MP_OBJ_FROM_PTR(mp_obj_get_type(rhs)), MP_OBJ_FROM_PTR(&mp_type_tuple))) {
                 return MP_OBJ_NULL; // op not supported
             }