diff --git a/l10n_it_fatturapa_out/models/partner.py b/l10n_it_fatturapa_out/models/partner.py
index 19cb4f972fef..bca0175481b3 100644
--- a/l10n_it_fatturapa_out/models/partner.py
+++ b/l10n_it_fatturapa_out/models/partner.py
@@ -1,4 +1,5 @@
 # Copyright 2019 Roberto Fichera <roberto.fichera@levelprime.com>
+# Copyright 2023 Simone Rubino - Aion Tech
 # License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl).
 
 from odoo import _, api, fields, models
@@ -11,7 +12,10 @@ class ResPartner(models.Model):
     max_invoice_in_xml = fields.Integer(
         string="Max Invoice # in XML",
         default=lambda self: self.env.company.max_invoice_in_xml,
-        help="Maximum number of invoices to group in a single " "XML file. 0=Unlimited",
+        help="Maximum number of invoices to group in a single "
+        "XML file.\n"
+        "If this is 0, then the number configured "
+        "in the account settings is considered.",
     )
 
     @api.constrains("max_invoice_in_xml")
diff --git a/l10n_it_fatturapa_out/tests/test_fatturapa_xml_validation.py b/l10n_it_fatturapa_out/tests/test_fatturapa_xml_validation.py
index 66addab8a204..5576b51f84e9 100644
--- a/l10n_it_fatturapa_out/tests/test_fatturapa_xml_validation.py
+++ b/l10n_it_fatturapa_out/tests/test_fatturapa_xml_validation.py
@@ -1,7 +1,7 @@
 # Copyright 2014 Davide Corio
 # Copyright 2015-2016 Lorenzo Battistini - Agile Business Group
 # Copyright 2018-2019 Alex Comba - Agile Business Group
-# Copyright 2024 Simone Rubino - Aion Tech
+# Copyright 2023 Simone Rubino - Aion Tech
 # License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
 
 import base64
@@ -1113,3 +1113,71 @@ def test_18_xml_export(self):
         # XML doc to be validated
         xml_content = base64.decodebytes(attachment.datas)
         self.check_content(xml_content, "IT06363391001_00018.xml")
+
+    def _get_multiple_invoices(self, partner, invoices_number=2):
+        """Create `invoices_number` invoices for `partner`."""
+        invoices = self.invoice_model.browse()
+        for _ in range(invoices_number):
+            invoices |= self.init_invoice(
+                "out_invoice",
+                partner=partner,
+                amounts=[
+                    100,
+                ],
+            )
+        invoices.action_post()
+        return invoices
+
+    def test_max_invoice_number_unlimited(self):
+        """Check that when both partner and company do not have any max value,
+        only one attachment is created."""
+
+        # pre-condition: partner and company do not have any max value
+        company = self.company
+        self.assertEqual(company.max_invoice_in_xml, 0)
+        partner = self.res_partner_fatturapa_0
+        self.assertEqual(partner.max_invoice_in_xml, 0)
+
+        # Create two invoices
+        invoices = self._get_multiple_invoices(partner)
+        self.run_wizard(invoices.ids)
+
+        # Check that only one attachment is created
+        attachments_nbr = len(invoices.mapped("fatturapa_attachment_out_id"))
+        self.assertEqual(attachments_nbr, 1)
+
+    def test_max_invoice_number_partner(self):
+        """Check that when partner has a max value, company value is ignored and
+        many attachments are created."""
+
+        # pre-condition: partner has a value
+        company = self.company
+        self.assertEqual(company.max_invoice_in_xml, 0)
+        partner = self.res_partner_fatturapa_0
+        partner.max_invoice_in_xml = 1
+
+        # Create two invoices
+        invoices = self._get_multiple_invoices(partner)
+        self.run_wizard(invoices.ids)
+
+        # Check that two attachments are created
+        attachments_nbr = len(invoices.mapped("fatturapa_attachment_out_id"))
+        self.assertEqual(attachments_nbr, 2)
+
+    def test_max_invoice_number_company(self):
+        """Check that when company has a max value and partner does not,
+        many attachments are created."""
+
+        # pre-condition: only company has a value
+        company = self.company
+        company.max_invoice_in_xml = 1
+        partner = self.res_partner_fatturapa_0
+        self.assertEqual(partner.max_invoice_in_xml, 0)
+
+        # Create two invoices
+        invoices = self._get_multiple_invoices(partner)
+        self.run_wizard(invoices.ids)
+
+        # Check that two attachments are created
+        attachments_nbr = len(invoices.mapped("fatturapa_attachment_out_id"))
+        self.assertEqual(attachments_nbr, 2)
diff --git a/l10n_it_fatturapa_out/wizard/wizard_export_fatturapa.py b/l10n_it_fatturapa_out/wizard/wizard_export_fatturapa.py
index d232ee8e0d3e..dc73818baade 100644
--- a/l10n_it_fatturapa_out/wizard/wizard_export_fatturapa.py
+++ b/l10n_it_fatturapa_out/wizard/wizard_export_fatturapa.py
@@ -3,6 +3,7 @@
 # Copyright 2018 Simone Rubino - Agile Business Group
 # Copyright 2018 Sergio Corato
 # Copyright 2019 Alex Comba - Agile Business Group
+# Copyright 2023 Simone Rubino - Aion Tech
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
 
 import base64
@@ -217,11 +218,13 @@ def split_list(my_list, size):
             if invoice.partner_id not in res:
                 res[invoice.partner_id] = []
             res[invoice.partner_id].append(invoice.id)
+
+        company = self.env.company
+        company_max_invoice = company.max_invoice_in_xml
         for partner_id in res.keys():
-            if partner_id.max_invoice_in_xml:
-                res[partner_id] = list(
-                    split_list(res[partner_id], partner_id.max_invoice_in_xml)
-                )
+            max_invoice = partner_id.max_invoice_in_xml or company_max_invoice
+            if max_invoice:
+                res[partner_id] = list(split_list(res[partner_id], max_invoice))
             else:
                 res[partner_id] = [res[partner_id]]
         # The returned dictionary contains a plain res.partner object as key