diff --git a/src/fellchensammlung/management/commands/mask_contact_data.py b/src/fellchensammlung/management/commands/mask_contact_data.py
new file mode 100644
index 0000000..f7accb1
--- /dev/null
+++ b/src/fellchensammlung/management/commands/mask_contact_data.py
@@ -0,0 +1,13 @@
+from django.core.management import BaseCommand
+from fellchensammlung.tools.admin import mask_organization_contact_data
+
+
+class Command(BaseCommand):
+    help = 'Mask e-mail addresses and phone numbers of organizations for testing purposes.'
+
+    def add_arguments(self, parser):
+        parser.add_argument("domain", type=str)
+
+    def handle(self, *args, **options):
+        domain = options["domain"]
+        mask_organization_contact_data(domain)
diff --git a/src/fellchensammlung/tools/admin.py b/src/fellchensammlung/tools/admin.py
index 11b890a..0c8073c 100644
--- a/src/fellchensammlung/tools/admin.py
+++ b/src/fellchensammlung/tools/admin.py
@@ -1,5 +1,6 @@
 import logging
 
+from random import randint
 from notfellchen import settings
 from django.utils import timezone
 from datetime import timedelta
@@ -139,3 +140,18 @@ def send_test_email(email):
     to = email
 
     mail.send_mail(subject, plain_message, from_email, [to], html_message=html_message)
+
+
+def mask_organization_contact_data(catchall_domain="example.org"):
+    """
+    Masks e-mails, so they are all sent to one domain, preferably a catchall domain.
+    """
+    rescue_orgs_with_phone_number = RescueOrganization.objects.filter(phone_number__isnull=False)
+    for rescue_org_with_phone_number in rescue_orgs_with_phone_number:
+        rescue_org_with_phone_number.phone_number = randint(100000000000, 1000000000000)
+        rescue_org_with_phone_number.save()
+    rescue_orgs_with_email = RescueOrganization.objects.filter(email__isnull=False)
+    for rescue_org_with_email in rescue_orgs_with_email:
+        rescue_org_with_email.email = f"{rescue_org_with_email.email.replace('@', '-')}@{catchall_domain}"
+        rescue_org_with_email.save()
+
diff --git a/src/tests/test_admin_tasks.py b/src/tests/test_admin_tasks.py
index cd66f28..780c9f8 100644
--- a/src/tests/test_admin_tasks.py
+++ b/src/tests/test_admin_tasks.py
@@ -2,12 +2,12 @@ from datetime import timedelta
 from django.utils import timezone
 
 from fellchensammlung.tools.admin import get_unchecked_adoption_notices, deactivate_unchecked_adoption_notices, \
-    deactivate_404_adoption_notices
+    deactivate_404_adoption_notices, mask_organization_contact_data
 from fellchensammlung.tools.misc import is_404
 from django.test import TestCase
 
 from model_bakery import baker
-from fellchensammlung.models import AdoptionNotice
+from fellchensammlung.models import AdoptionNotice, RescueOrganization
 
 
 class DeactivationTest(TestCase):
@@ -96,3 +96,21 @@ class PingTest(TestCase):
         self.adoption2.refresh_from_db()
         self.assertTrue(self.adoption1.is_active)
         self.assertFalse(self.adoption2.is_active)
+
+
+class MaskingTest(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.rescue1 = baker.make(RescueOrganization, email="test1@example.com", )
+        cls.rescue2 = baker.make(RescueOrganization, email="test-2@example.com", phone_number="0123456789", )
+
+    def test_masking(self):
+        mask_organization_contact_data()
+        self.assertEqual(RescueOrganization.objects.count(), 2)
+
+        # Ensure that the rescues are pulled from the database again, otherwise this test will fail
+        self.rescue1.refresh_from_db()
+        self.rescue2.refresh_from_db()
+        self.assertNotEqual(self.rescue1.phone_number, "0123456789")
+        self.assertEqual(self.rescue1.email, "test1-example.com@example.org")
+        self.assertEqual(self.rescue2.email, "test-2-example.com@example.org")