diff --git a/portal/tests/test_independent_student.py b/portal/tests/test_independent_student.py
index 9ec013bfb..979ffb001 100644
--- a/portal/tests/test_independent_student.py
+++ b/portal/tests/test_independent_student.py
@@ -21,7 +21,7 @@
 from django.urls import reverse
 from selenium.webdriver.common.by import By
 from selenium.webdriver.support.wait import WebDriverWait
-from unittest.mock import patch, ANY
+from unittest.mock import patch, ANY, Mock
 
 from portal.forms.error_messages import INVALID_LOGIN_MESSAGE
 
@@ -139,7 +139,7 @@ def test_signup_invalid_name_fails(self):
         assert response.status_code == 200
 
     @patch("common.mail.send_dotdigital_email")
-    def test_signup_under_13_sends_parent_email(self, mock_send_dotdigital_email):
+    def test_signup_under_13_sends_parent_email(self, mock_send_dotdigital_email: Mock):
         c = Client()
 
         response = c.post(
diff --git a/portal/tests/test_ratelimit.py b/portal/tests/test_ratelimit.py
index fb6e08efd..17d2ec233 100644
--- a/portal/tests/test_ratelimit.py
+++ b/portal/tests/test_ratelimit.py
@@ -18,6 +18,7 @@
 from django.test import Client, TestCase
 from django.urls import reverse
 from django.urls import reverse_lazy
+from unittest.mock import patch, Mock, ANY
 
 from portal.helpers.ratelimit import get_ratelimit_count_for_user
 from portal.views.login import has_user_lockout_expired
@@ -433,7 +434,8 @@ def test_lockout_reset_tracking(self):
 
 
 @pytest.mark.django_db
-def test_teacher_already_registered_email(client):
+@patch("common.mail.send_dotdigital_email")
+def test_teacher_already_registered_email(client, mock_send_dotdigital_email: Mock):
     first_name, last_name, email, password = generate_details()
     register_url = reverse("register")
     data = {
@@ -448,19 +450,20 @@ def test_teacher_already_registered_email(client):
 
     # Register the teacher first time, there should be a registration email
     client.post(register_url, data)
-    assert len(mail.outbox) == 1
+    mock_send_dotdigital_email.assert_called_once_with(1551577, ANY, ANY)
 
     # Register with the same email again, there should also be an already registered email
     client.post(register_url, data)
-    assert len(mail.outbox) == 2
+    assert len(mail.outbox) == 1
 
     # Register with the same email one more time, there shouldn't be any new emails
     client.post(register_url, data)
-    assert len(mail.outbox) == 2
+    assert len(mail.outbox) == 1
 
 
 @pytest.mark.django_db
-def test_independent_student_already_registered_email(client):
+@patch("common.mail.send_dotdigital_email")
+def test_independent_student_already_registered_email(client, mock_send_dotdigital_email: Mock):
     name, username, email_address, password = generate_independent_student_details()
     register_url = reverse("register")
     data = {
@@ -477,12 +480,12 @@ def test_independent_student_already_registered_email(client):
 
     # Register the independent student first time, there should be a registration email
     client.post(register_url, data)
-    assert len(mail.outbox) == 1
+    mock_send_dotdigital_email.assert_called_once_with(1551577, ANY, ANY)
 
     # Register with the same email again, there should also be an already registered email
     client.post(register_url, data)
-    assert len(mail.outbox) == 2
+    assert len(mail.outbox) == 1
 
     # Reset mock and register with the same email one more time, there shouldn't be any new emails
     client.post(register_url, data)
-    assert len(mail.outbox) == 2
+    assert len(mail.outbox) == 1