diff --git a/addons/account/models/account_invoice.py b/addons/account/models/account_invoice.py
index c932be3345b..ba3c84e7525 100644
--- a/addons/account/models/account_invoice.py
+++ b/addons/account/models/account_invoice.py
@@ -567,7 +567,7 @@ class AccountInvoice(models.Model):
                 if not val.get('account_analytic_id') and line.account_analytic_id and val['account_id'] == line.account_id.id:
                     val['account_analytic_id'] = line.account_analytic_id.id
 
-                key = tax['id']
+                key = str(tax['id']) + '-' + str(val['account_id'])
                 if key not in tax_grouped:
                     tax_grouped[key] = val
                 else: