diff --git a/addons/l10n_ch/models/account_invoice.py b/addons/l10n_ch/models/account_invoice.py
index b8982977552..ec2a94abef9 100644
--- a/addons/l10n_ch/models/account_invoice.py
+++ b/addons/l10n_ch/models/account_invoice.py
@@ -185,3 +185,17 @@ class AccountInvoice(models.Model):
         if self.env.context.get('l10n_ch_mark_isr_as_sent'):
             self.filtered(lambda inv: not inv.l10n_ch_isr_sent).write({'l10n_ch_isr_sent': True})
         return super(AccountInvoice, self.with_context(mail_post_autofollow=True)).message_post(**kwargs)
+
+    def _get_reference_ch_invoice(self):
+        """ This sets ISR reference number which is generated based on customer's `Bank Account` and set it as
+        `Payment Reference` of the invoice when invoice's journal is using Switzerland's communication standard
+        """
+        self.ensure_one()
+        return self.l10n_ch_isr_number_spaced
+
+    def _get_reference_ch_partner(self):
+        """ This sets ISR reference number which is generated based on customer's `Bank Account` and set it as
+        `Payment Reference` of the invoice when invoice's journal is using Switzerland's communication standard
+        """
+        self.ensure_one()
+        return self.l10n_ch_isr_number_spaced
diff --git a/addons/l10n_ch/models/account_journal.py b/addons/l10n_ch/models/account_journal.py
index a42e163a299..85646dfa396 100644
--- a/addons/l10n_ch/models/account_journal.py
+++ b/addons/l10n_ch/models/account_journal.py
@@ -14,6 +14,7 @@ class AccountJournal(models.Model):
 
     # creation of bank journals by giving the account number, allow craetion of the
     l10n_ch_postal = fields.Char(related='bank_account_id.l10n_ch_postal', readonly=False)
+    invoice_reference_model = fields.Selection(selection_add=[('ch', 'Switzerland')])
 
     @api.model
     def create(self, vals):