diff --git a/synapse/types/__init__.py b/synapse/types/__init__.py
index b42893e39d..e901210e65 100644
--- a/synapse/types/__init__.py
+++ b/synapse/types/__init__.py
@@ -1651,7 +1651,7 @@ class UserInfo:
         consent_server_notice_sent:  Version of policy documents the user has been sent.
         consent_version:  Version of policy documents the user has consented to.
         consent_ts: Time the user consented
-        creation_ts:  Creation timestamp of the user.
+        creation_ts:  Creation timestamp of the user (in seconds).
         is_admin:  True if the user is an admin.
         is_deactivated:  True if the user has been deactivated.
         is_guest:  True if the user is a guest user.
diff --git a/tests/module_api/test_api.py b/tests/module_api/test_api.py
index b4b14c87b9..89aadd09d4 100644
--- a/tests/module_api/test_api.py
+++ b/tests/module_api/test_api.py
@@ -85,6 +85,7 @@ class ModuleApiTestCase(BaseModuleApiTestCase):
     def test_can_register_user(self) -> None:
         """Tests that an external module can register a user"""
         # Register a new user
+        register_ts = int(self.clock.time_msec())
         user_id, access_token = self.get_success(
             self.module_api.register(
                 "bob", displayname="Bobberino", emails=["bob@bobinator.bob"]
@@ -105,8 +106,8 @@ class ModuleApiTestCase(BaseModuleApiTestCase):
         self.assertEqual(email.address, "bob@bobinator.bob")
 
         # Should these be 0?
-        self.assertEqual(email.validated_at, 0)
-        self.assertEqual(email.added_at, 0)
+        self.assertEqual(email.validated_at, register_ts)
+        self.assertEqual(email.added_at, register_ts)
 
         # Check that the displayname was assigned
         displayname = self.get_success(
diff --git a/tests/storage/test_registration.py b/tests/storage/test_registration.py
index 7ee81fabb6..5a5624f272 100644
--- a/tests/storage/test_registration.py
+++ b/tests/storage/test_registration.py
@@ -39,6 +39,7 @@ class RegistrationStoreTestCase(HomeserverTestCase):
         self.device_id = "akgjhdjklgshg"
 
     def test_register(self) -> None:
+        register_ts_seconds = int(self.clock.time())
         self.get_success(self.store.register_user(self.user_id, self.pwhash))
 
         self.assertEqual(
@@ -50,7 +51,7 @@ class RegistrationStoreTestCase(HomeserverTestCase):
                 consent_ts=None,
                 consent_version=None,
                 appservice_id=None,
-                creation_ts=0,
+                creation_ts=register_ts_seconds,
                 user_type=None,
                 is_deactivated=False,
                 locked=False,