diff --git a/hr_holidays_google_calendar/__init__.py b/hr_holidays_google_calendar/__init__.py
new file mode 100644
index 0000000..0650744
--- /dev/null
+++ b/hr_holidays_google_calendar/__init__.py
@@ -0,0 +1 @@
+from . import models
diff --git a/hr_holidays_google_calendar/__manifest__.py b/hr_holidays_google_calendar/__manifest__.py
new file mode 100644
index 0000000..20655ba
--- /dev/null
+++ b/hr_holidays_google_calendar/__manifest__.py
@@ -0,0 +1,37 @@
+##############################################################################
+#
+#    Copyright (C) 2024  ADHOC SA  (http://www.adhoc.com.ar)
+#    All Rights Reserved.
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU Affero General Public License as
+#    published by the Free Software Foundation, either version 3 of the
+#    License, or (at your option) any later version.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU Affero General Public License for more details.
+#
+#    You should have received a copy of the GNU Affero General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+##############################################################################
+{
+    "name": "Holidays Google Calendar",
+    "version": "19.0.1.0.0",
+    "category": "Human Resources",
+    "summary": "Suppress Google Calendar invitations when approving time off",
+    "author": "ADHOC SA",
+    "website": "www.adhoc.com.ar",
+    "license": "AGPL-3",
+    "depends": [
+        "hr_holidays",
+        "google_calendar",
+    ],
+    "data": [],
+    "demo": [],
+    "installable": True,
+    "auto_install": True,
+    "application": False,
+}
diff --git a/hr_holidays_google_calendar/models/__init__.py b/hr_holidays_google_calendar/models/__init__.py
new file mode 100644
index 0000000..ba757cb
--- /dev/null
+++ b/hr_holidays_google_calendar/models/__init__.py
@@ -0,0 +1 @@
+from . import calendar_event
diff --git a/hr_holidays_google_calendar/models/calendar_event.py b/hr_holidays_google_calendar/models/calendar_event.py
new file mode 100644
index 0000000..8c44685
--- /dev/null
+++ b/hr_holidays_google_calendar/models/calendar_event.py
@@ -0,0 +1,14 @@
+from odoo import models
+from odoo.addons.google_calendar.models.google_sync import TIMEOUT
+
+
+class CalendarEvent(models.Model):
+    _inherit = "calendar.event"
+
+    def _google_insert(self, google_service, values, timeout=TIMEOUT):
+        # When hr_holidays creates a leave event it sets no_mail_to_attendees=True,
+        # meaning Odoo itself must not notify attendees. Honour that restriction in
+        # Google Calendar too by suppressing the sendUpdates notification.
+        if self.env.context.get("no_mail_to_attendees"):
+            self = self.with_context(send_updates=False)
+        return super()._google_insert(google_service, values, timeout=timeout)
diff --git a/hr_holidays_microsoft_calendar/__init__.py b/hr_holidays_microsoft_calendar/__init__.py
new file mode 100644
index 0000000..0650744
--- /dev/null
+++ b/hr_holidays_microsoft_calendar/__init__.py
@@ -0,0 +1 @@
+from . import models
diff --git a/hr_holidays_microsoft_calendar/__manifest__.py b/hr_holidays_microsoft_calendar/__manifest__.py
new file mode 100644
index 0000000..0cd4f93
--- /dev/null
+++ b/hr_holidays_microsoft_calendar/__manifest__.py
@@ -0,0 +1,37 @@
+##############################################################################
+#
+#    Copyright (C) 2024  ADHOC SA  (http://www.adhoc.com.ar)
+#    All Rights Reserved.
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU Affero General Public License as
+#    published by the Free Software Foundation, either version 3 of the
+#    License, or (at your option) any later version.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU Affero General Public License for more details.
+#
+#    You should have received a copy of the GNU Affero General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+##############################################################################
+{
+    "name": "Holidays Microsoft Calendar",
+    "version": "19.0.1.0.0",
+    "category": "Human Resources",
+    "summary": "Suppress Outlook invitations when approving time off",
+    "author": "ADHOC SA",
+    "website": "www.adhoc.com.ar",
+    "license": "AGPL-3",
+    "depends": [
+        "hr_holidays",
+        "microsoft_calendar",
+    ],
+    "data": [],
+    "demo": [],
+    "installable": True,
+    "auto_install": True,
+    "application": False,
+}
diff --git a/hr_holidays_microsoft_calendar/models/__init__.py b/hr_holidays_microsoft_calendar/models/__init__.py
new file mode 100644
index 0000000..ba757cb
--- /dev/null
+++ b/hr_holidays_microsoft_calendar/models/__init__.py
@@ -0,0 +1 @@
+from . import calendar_event
diff --git a/hr_holidays_microsoft_calendar/models/calendar_event.py b/hr_holidays_microsoft_calendar/models/calendar_event.py
new file mode 100644
index 0000000..d03c1d7
--- /dev/null
+++ b/hr_holidays_microsoft_calendar/models/calendar_event.py
@@ -0,0 +1,15 @@
+from odoo import models
+
+
+class CalendarEvent(models.Model):
+    _inherit = "calendar.event"
+
+    def _microsoft_values(self, fields_to_sync, initial_values=()):
+        # When hr_holidays creates a leave event it sets no_mail_to_attendees=True,
+        # meaning Odoo itself must not notify attendees. Honour that restriction for
+        # Outlook too by removing attendees from the Graph API payload so Microsoft
+        # does not send invitation emails on its side.
+        values = super()._microsoft_values(fields_to_sync, initial_values)
+        if self.env.context.get("no_mail_to_attendees"):
+            values.pop("attendees", None)
+        return values