diff --git a/invoice.py b/invoice.py
index b67e20f..f70eae6 100644
--- a/invoice.py
+++ b/invoice.py
@@ -1,12 +1,10 @@
 # This file is part account_invoice_taxes_required module for Tryton.
 # The COPYRIGHT file at the top level of this repository contains
 # the full copyright notices and license terms.
-
 from trytond.pool import Pool, PoolMeta
 from trytond.i18n import gettext
 from trytond.exceptions import UserError
-
-__all__ = ['Invoice', 'InvoiceLine']
+from trytond.model import fields
 
 
 class Invoice(metaclass=PoolMeta):
@@ -15,6 +13,7 @@ class Invoice(metaclass=PoolMeta):
     @classmethod
     def validate(cls, invoices):
         InvoiceLine = Pool().get('account.invoice.line')
+
         super(Invoice, cls).validate(invoices)
         for invoice in invoices:
             InvoiceLine.validate(invoice.lines)
@@ -22,6 +21,11 @@ class Invoice(metaclass=PoolMeta):
 
 class InvoiceLine(metaclass=PoolMeta):
     __name__ = 'account.invoice.line'
+    taxes_required = fields.Boolean('Taxes Required', readonly=True)
+
+    @classmethod
+    def default_taxes_required(cls):
+        return True
 
     @classmethod
     def validate(cls, lines):
@@ -30,8 +34,10 @@ class InvoiceLine(metaclass=PoolMeta):
             line.check_tax_required()
 
     def check_tax_required(self):
-        if not self.invoice or self.invoice.state in ('draft', 'cancelled') or \
-                self.type != 'line':
+        if (not self.invoice
+                or not self.taxes_required
+                or self.invoice.state in ('draft', 'cancelled')
+                or self.type != 'line'):
             return
         if not self.taxes:
             raise UserError(gettext(
diff --git a/tests/scenario_invoice_taxes_required.rst b/tests/scenario_invoice_taxes_required.rst
index 87fca3a..6b71257 100644
--- a/tests/scenario_invoice_taxes_required.rst
+++ b/tests/scenario_invoice_taxes_required.rst
@@ -102,6 +102,8 @@ Create invoice Without Taxes::
     >>> line.description = 'Test'
     >>> line.quantity = 1
     >>> line.unit_price = Decimal(20)
+    >>> line.taxes_required == True
+    True
     >>> invoice.untaxed_amount
     Decimal('220.00')
     >>> invoice.tax_amount