diff --git a/addons/point_of_sale/models/__init__.py b/addons/point_of_sale/models/__init__.py
index 2934be43e10..9023c405f2c 100644
--- a/addons/point_of_sale/models/__init__.py
+++ b/addons/point_of_sale/models/__init__.py
@@ -12,4 +12,5 @@ from . import pos_order
 from . import pos_session
 from . import product
 from . import res_partner
+from . import res_company
 from . import res_config_settings
diff --git a/addons/point_of_sale/models/pos_session.py b/addons/point_of_sale/models/pos_session.py
index 02ddaf2fd93..502536c785f 100644
--- a/addons/point_of_sale/models/pos_session.py
+++ b/addons/point_of_sale/models/pos_session.py
@@ -158,6 +158,14 @@ class PosSession(models.Model):
             ]) > 1:
             raise ValidationError(_("Another session is already opened for this point of sale."))
 
+    @api.constrains('start_at')
+    def _check_start_date(self):
+        for record in self:
+            company = record.config_id.journal_id.company_id
+            start_date = record.start_at.date()
+            if (company.period_lock_date and start_date <= company.period_lock_date) or (company.fiscalyear_lock_date and start_date <= company.fiscalyear_lock_date):
+                raise ValidationError(_("You cannot create a session before the accounting lock date."))
+
     @api.model
     def create(self, values):
         config_id = values.get('config_id') or self.env.context.get('default_config_id')
diff --git a/addons/point_of_sale/models/res_company.py b/addons/point_of_sale/models/res_company.py
new file mode 100644
index 00000000000..91a833ba7d6
--- /dev/null
+++ b/addons/point_of_sale/models/res_company.py
@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+
+from odoo import api, models, fields, _
+from odoo.exceptions import ValidationError
+
+class ResCompany(models.Model):
+    _inherit = 'res.company'
+
+    @api.constrains('period_lock_date', 'fiscalyear_lock_date')
+    def validate_period_lock_date(self):
+        """ This constrains makes it impossible to change the period lock date if
+        some open POS session exists into it. Without that, these POS sessions
+        would trigger an error message saying that the period has been locked when
+        trying to close them.
+        """
+        pos_session_model = self.env['pos.session']
+        for record in self:
+            sessions_in_period = pos_session_model.search([('state', '!=', 'closed'), '|', ('start_at', '<=', record.period_lock_date), ('start_at', '<=', record.fiscalyear_lock_date)])
+            if sessions_in_period:
+                sessions_str = ', '.join(sessions_in_period.mapped('name'))
+                raise ValidationError(_("Please close all the point of sale sessions in this period before closing it. Open sessions are: %s ") % (sessions_str))
\ No newline at end of file