diff --git a/addons/purchase/purchase.py b/addons/purchase/purchase.py
index 1ca44c91072..bd445dd94a5 100644
--- a/addons/purchase/purchase.py
+++ b/addons/purchase/purchase.py
@@ -1336,6 +1336,7 @@ class procurement_order(osv.osv):
         pricelist_obj = self.pool.get('product.pricelist')
         prod_obj = self.pool.get('product.product')
         acc_pos_obj = self.pool.get('account.fiscal.position')
+        po_obj = self.pool.get('purchase.order')
 
         seller_qty = procurement.product_id.seller_qty if procurement.location_id.usage != 'customer' else 0.0
         pricelist_id = partner.property_product_pricelist_purchase.id
@@ -1350,7 +1351,12 @@ class procurement_order(osv.osv):
         new_context.update({'lang': partner.lang, 'partner_id': partner.id})
         product = prod_obj.browse(cr, uid, procurement.product_id.id, context=new_context)
         taxes_ids = procurement.product_id.supplier_taxes_id
-        taxes = acc_pos_obj.map_tax(cr, uid, partner.property_account_position, taxes_ids)
+        # It is necessary to have the appropriate fiscal position to get the right tax mapping
+        fiscal_position = False
+        fiscal_position_id = po_obj.onchange_partner_id(cr, uid, None, partner.id, context=context)['value']['fiscal_position']
+        if fiscal_position_id:
+            fiscal_position = acc_pos_obj.browse(cr, uid, fiscal_position_id, context=context)
+        taxes = acc_pos_obj.map_tax(cr, uid, fiscal_position, taxes_ids)
         name = product.display_name
         if product.description_purchase:
             name += '\n' + product.description_purchase
@@ -1462,7 +1468,7 @@ class procurement_order(osv.osv):
                         'currency_id': partner.property_product_pricelist_purchase and partner.property_product_pricelist_purchase.currency_id.id or procurement.company_id.currency_id.id,
                         'date_order': purchase_date.strftime(DEFAULT_SERVER_DATETIME_FORMAT),
                         'company_id': procurement.company_id.id,
-                        'fiscal_position': partner.property_account_position and partner.property_account_position.id or False,
+                        'fiscal_position': po_obj.onchange_partner_id(cr, uid, None, partner.id, context=context)['value']['fiscal_position'],
                         'payment_term_id': partner.property_supplier_payment_term.id or False,
                         'dest_address_id': procurement.partner_dest_id.id,
                     }