diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index 90057fbe9a7..082f5711195 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -244,7 +244,7 @@ class purchase_order(osv.osv):
     _name = "purchase.order"
     _inherit = ['mail.thread', 'ir.needaction_mixin']
     _description = "Purchase Order"
-    _order = "name desc"
+    _order = 'date_order desc, id desc'
 
     def create(self, cr, uid, vals, context=None):
         if vals.get('name','/')=='/':
diff --git a/addons/sale/sale.py b/addons/sale/sale.py
index 668685ed342..bdadc4489da 100644
--- a/addons/sale/sale.py
+++ b/addons/sale/sale.py
@@ -266,7 +266,7 @@ class sale_order(osv.osv):
     _sql_constraints = [
         ('name_uniq', 'unique(name, company_id)', 'Order Reference must be unique per Company!'),
     ]
-    _order = 'name desc'
+    _order = 'date_order desc, id desc'
 
     # Form filling
     def unlink(self, cr, uid, ids, context=None):