diff --git a/addons/stock/wizard/stock_transfer_details.py b/addons/stock/wizard/stock_transfer_details.py
index 17f302f6317..ed03413f5fa 100644
--- a/addons/stock/wizard/stock_transfer_details.py
+++ b/addons/stock/wizard/stock_transfer_details.py
@@ -48,8 +48,7 @@ class stock_transfer_details(models.TransientModel):
         picking = self.pool.get('stock.picking').browse(cr, uid, picking_id, context=context)
         items = []
         packs = []
-        if not picking.pack_operation_ids:
-            picking.do_prepare_partial()
+        picking.do_prepare_partial()
         for op in picking.pack_operation_ids:
             item = {
                 'packop_id': op.id,