diff --git a/addons/account/account.py b/addons/account/account.py
index 6368149ba5c..6cc7125db1c 100644
--- a/addons/account/account.py
+++ b/addons/account/account.py
@@ -2067,6 +2067,8 @@ class account_tax(osv.osv):
                 amount = amount2
                 child_tax = self._unit_compute(cr, uid, tax.child_ids, amount, product, partner, quantity)
                 res.extend(child_tax)
+                for child in child_tax:
+                    amount2 += child.get('amount', 0.0)
                 if tax.child_depend:
                     for r in res:
                         for name in ('base','ref_base'):