diff --git a/readthedocs/config/tests/test_config.py b/readthedocs/config/tests/test_config.py
index a5b5907b887..5ccf306f611 100644
--- a/readthedocs/config/tests/test_config.py
+++ b/readthedocs/config/tests/test_config.py
@@ -4,7 +4,7 @@
 from collections import OrderedDict
 
 import pytest
-from mock import DEFAULT, patch
+from unittest.mock import DEFAULT, patch
 from pytest import raises
 
 from readthedocs.config import (
diff --git a/readthedocs/config/tests/test_validation.py b/readthedocs/config/tests/test_validation.py
index c46331c5d8d..400657b2c24 100644
--- a/readthedocs/config/tests/test_validation.py
+++ b/readthedocs/config/tests/test_validation.py
@@ -1,6 +1,6 @@
 import os
 
-from mock import patch
+from unittest.mock import patch
 from pytest import raises
 
 from readthedocs.config.validation import (
diff --git a/readthedocs/gold/tests/test_forms.py b/readthedocs/gold/tests/test_forms.py
index c379bba3b79..a953ba7c12e 100644
--- a/readthedocs/gold/tests/test_forms.py
+++ b/readthedocs/gold/tests/test_forms.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 
diff --git a/readthedocs/gold/tests/test_signals.py b/readthedocs/gold/tests/test_signals.py
index f55e0b53be8..73f7957bf9f 100644
--- a/readthedocs/gold/tests/test_signals.py
+++ b/readthedocs/gold/tests/test_signals.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 
diff --git a/readthedocs/proxito/tests/test_full.py b/readthedocs/proxito/tests/test_full.py
index 8d929c62eda..1633134edd7 100644
--- a/readthedocs/proxito/tests/test_full.py
+++ b/readthedocs/proxito/tests/test_full.py
@@ -3,7 +3,7 @@
 import os
 
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.conf import settings
 from django.http import HttpResponse
 from django.test.utils import override_settings
diff --git a/readthedocs/rtd_tests/base.py b/readthedocs/rtd_tests/base.py
index e7d8f8409e0..d5deb550e63 100644
--- a/readthedocs/rtd_tests/base.py
+++ b/readthedocs/rtd_tests/base.py
@@ -11,7 +11,7 @@
 from django.contrib.messages.storage.fallback import FallbackStorage
 from django.contrib.sessions.middleware import SessionMiddleware
 from django.test import RequestFactory, TestCase
-from mock import patch
+from unittest.mock import patch
 
 
 log = logging.getLogger(__name__)
diff --git a/readthedocs/rtd_tests/mocks/environment.py b/readthedocs/rtd_tests/mocks/environment.py
index 6928d4cec3c..169a7a8a066 100644
--- a/readthedocs/rtd_tests/mocks/environment.py
+++ b/readthedocs/rtd_tests/mocks/environment.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 # pylint: disable=missing-docstring
-import mock
+from unittest import mock
 
 
 class EnvironmentMockGroup:
diff --git a/readthedocs/rtd_tests/mocks/mock_api.py b/readthedocs/rtd_tests/mocks/mock_api.py
index ef33f7d6d49..c523cd8567c 100644
--- a/readthedocs/rtd_tests/mocks/mock_api.py
+++ b/readthedocs/rtd_tests/mocks/mock_api.py
@@ -2,7 +2,7 @@
 import json
 from contextlib import contextmanager
 
-import mock
+from unittest import mock
 
 
 # Mock tastypi API.
diff --git a/readthedocs/rtd_tests/mocks/paths.py b/readthedocs/rtd_tests/mocks/paths.py
index 787eabff923..99806a9158b 100644
--- a/readthedocs/rtd_tests/mocks/paths.py
+++ b/readthedocs/rtd_tests/mocks/paths.py
@@ -3,7 +3,7 @@
 import os
 import re
 
-import mock
+from unittest import mock
 
 
 def fake_paths(check):
diff --git a/readthedocs/rtd_tests/tests/projects/test_admin_actions.py b/readthedocs/rtd_tests/tests/projects/test_admin_actions.py
index dd25f4a13b4..27fecf65ba5 100644
--- a/readthedocs/rtd_tests/tests/projects/test_admin_actions.py
+++ b/readthedocs/rtd_tests/tests/projects/test_admin_actions.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django import urls
 from django.contrib.admin.helpers import ACTION_CHECKBOX_NAME
 from django.contrib.auth.models import User
diff --git a/readthedocs/rtd_tests/tests/test_api.py b/readthedocs/rtd_tests/tests/test_api.py
index 16ccdfa1d84..2966838e2ff 100644
--- a/readthedocs/rtd_tests/tests/test_api.py
+++ b/readthedocs/rtd_tests/tests/test_api.py
@@ -2,7 +2,7 @@
 import datetime
 import json
 
-import mock
+from unittest import mock
 from allauth.socialaccount.models import SocialAccount
 from django.contrib.auth.models import User
 from django.http import QueryDict
diff --git a/readthedocs/rtd_tests/tests/test_api_permissions.py b/readthedocs/rtd_tests/tests/test_api_permissions.py
index 4e91f419faa..66e636bcedc 100644
--- a/readthedocs/rtd_tests/tests/test_api_permissions.py
+++ b/readthedocs/rtd_tests/tests/test_api_permissions.py
@@ -1,7 +1,7 @@
 from functools import partial
 from unittest import TestCase
 
-from mock import Mock
+from unittest.mock import Mock
 
 from readthedocs.api.v2.permissions import APIRestrictedPermission
 
diff --git a/readthedocs/rtd_tests/tests/test_automation_rules.py b/readthedocs/rtd_tests/tests/test_automation_rules.py
index 274dbdf1f8d..2fff7bec77f 100644
--- a/readthedocs/rtd_tests/tests/test_automation_rules.py
+++ b/readthedocs/rtd_tests/tests/test_automation_rules.py
@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 import pytest
 from django_dynamic_fixture import get
 
diff --git a/readthedocs/rtd_tests/tests/test_backend.py b/readthedocs/rtd_tests/tests/test_backend.py
index acb0984aab4..f3efd762f6f 100644
--- a/readthedocs/rtd_tests/tests/test_backend.py
+++ b/readthedocs/rtd_tests/tests/test_backend.py
@@ -7,7 +7,7 @@
 
 import django_dynamic_fixture as fixture
 from django.contrib.auth.models import User
-from mock import Mock, patch
+from unittest.mock import Mock, patch
 
 from readthedocs.builds.constants import EXTERNAL
 from readthedocs.builds.models import Version
diff --git a/readthedocs/rtd_tests/tests/test_build_forms.py b/readthedocs/rtd_tests/tests/test_build_forms.py
index 0e2a4600f8d..19a7710a918 100644
--- a/readthedocs/rtd_tests/tests/test_build_forms.py
+++ b/readthedocs/rtd_tests/tests/test_build_forms.py
@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django.urls import reverse
diff --git a/readthedocs/rtd_tests/tests/test_build_notifications.py b/readthedocs/rtd_tests/tests/test_build_notifications.py
index 82e52823562..83f1bd5a765 100644
--- a/readthedocs/rtd_tests/tests/test_build_notifications.py
+++ b/readthedocs/rtd_tests/tests/test_build_notifications.py
@@ -6,7 +6,7 @@
 import django_dynamic_fixture as fixture
 from django.core import mail
 from django.test import TestCase
-from mock import patch
+from unittest.mock import patch
 
 from readthedocs.builds.models import Build, Version
 from readthedocs.projects.forms import WebHookForm
diff --git a/readthedocs/rtd_tests/tests/test_builds.py b/readthedocs/rtd_tests/tests/test_builds.py
index 118d322a3f3..e88e6b6f958 100644
--- a/readthedocs/rtd_tests/tests/test_builds.py
+++ b/readthedocs/rtd_tests/tests/test_builds.py
@@ -2,7 +2,7 @@
 import datetime
 import os
 
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django_dynamic_fixture import fixture, get
diff --git a/readthedocs/rtd_tests/tests/test_celery.py b/readthedocs/rtd_tests/tests/test_celery.py
index 76a92e10439..c5a103e61aa 100644
--- a/readthedocs/rtd_tests/tests/test_celery.py
+++ b/readthedocs/rtd_tests/tests/test_celery.py
@@ -7,7 +7,7 @@
 from django.contrib.auth.models import User
 from django_dynamic_fixture import get
 from messages_extends.models import Message
-from mock import MagicMock, patch
+from unittest.mock import MagicMock, patch
 
 from readthedocs.builds.constants import (
     BUILD_STATE_TRIGGERED,
diff --git a/readthedocs/rtd_tests/tests/test_config_integration.py b/readthedocs/rtd_tests/tests/test_config_integration.py
index 91cd707762f..43e5e9182ef 100644
--- a/readthedocs/rtd_tests/tests/test_config_integration.py
+++ b/readthedocs/rtd_tests/tests/test_config_integration.py
@@ -1,12 +1,12 @@
 import tempfile
 from os import path
 
-import mock
+from unittest import mock
 import pytest
 import yaml
 from django.test import TestCase
 from django_dynamic_fixture import get
-from mock import MagicMock, PropertyMock, patch
+from unittest.mock import MagicMock, PropertyMock, patch
 
 from readthedocs.builds.constants import BUILD_STATE_TRIGGERED, EXTERNAL
 from readthedocs.builds.models import Version
diff --git a/readthedocs/rtd_tests/tests/test_core_tags.py b/readthedocs/rtd_tests/tests/test_core_tags.py
index 64a3fc6b363..a203319d71f 100644
--- a/readthedocs/rtd_tests/tests/test_core_tags.py
+++ b/readthedocs/rtd_tests/tests/test_core_tags.py
@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 import pytest
 from django.conf import settings
 from django.test import TestCase
diff --git a/readthedocs/rtd_tests/tests/test_core_utils.py b/readthedocs/rtd_tests/tests/test_core_utils.py
index 813acc91907..dc2efb4ef60 100644
--- a/readthedocs/rtd_tests/tests/test_core_utils.py
+++ b/readthedocs/rtd_tests/tests/test_core_utils.py
@@ -2,11 +2,11 @@
 
 import os
 
-import mock
+from unittest import mock
 from django.http import Http404
 from django.test import TestCase
 from django_dynamic_fixture import get
-from mock import call
+from unittest.mock import call
 
 from readthedocs.builds.constants import LATEST
 from readthedocs.builds.models import Version
diff --git a/readthedocs/rtd_tests/tests/test_doc_builder.py b/readthedocs/rtd_tests/tests/test_doc_builder.py
index da7ce55df51..18148378941 100644
--- a/readthedocs/rtd_tests/tests/test_doc_builder.py
+++ b/readthedocs/rtd_tests/tests/test_doc_builder.py
@@ -2,14 +2,14 @@
 import tempfile
 from collections import namedtuple
 
-import mock
+from unittest import mock
 import py
 import pytest
 import yaml
 from django.test import TestCase
 from django.test.utils import override_settings
 from django_dynamic_fixture import get
-from mock import patch
+from unittest.mock import patch
 
 from readthedocs.builds.models import Version
 from readthedocs.doc_builder.backends.mkdocs import MkdocsHTML
diff --git a/readthedocs/rtd_tests/tests/test_doc_building.py b/readthedocs/rtd_tests/tests/test_doc_building.py
index 9b73f123bcf..b9219c0443d 100644
--- a/readthedocs/rtd_tests/tests/test_doc_building.py
+++ b/readthedocs/rtd_tests/tests/test_doc_building.py
@@ -12,13 +12,13 @@
 import tempfile
 import uuid
 
-import mock
+from unittest import mock
 import pytest
 from django.test import TestCase
 from django_dynamic_fixture import get
 from docker.errors import APIError as DockerAPIError
 from docker.errors import DockerException
-from mock import Mock, PropertyMock, mock_open, patch
+from unittest.mock import Mock, PropertyMock, mock_open, patch
 
 from readthedocs.builds.constants import BUILD_STATE_CLONING
 from readthedocs.builds.models import Version
diff --git a/readthedocs/rtd_tests/tests/test_doc_serving.py b/readthedocs/rtd_tests/tests/test_doc_serving.py
index 734ed3338b1..b2813c0e846 100644
--- a/readthedocs/rtd_tests/tests/test_doc_serving.py
+++ b/readthedocs/rtd_tests/tests/test_doc_serving.py
@@ -1,14 +1,14 @@
 import os
 
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.conf import settings
 from django.contrib.auth.models import User
 from django.http import Http404, HttpResponse
 from django.test import RequestFactory, TestCase
 from django.test.utils import override_settings
 from django.urls import reverse
-from mock import mock_open, patch
+from unittest.mock import mock_open, patch
 
 from readthedocs.builds.constants import LATEST, EXTERNAL, INTERNAL
 from readthedocs.builds.models import Version
diff --git a/readthedocs/rtd_tests/tests/test_footer.py b/readthedocs/rtd_tests/tests/test_footer.py
index f07e6a84946..7fff4a4aef9 100644
--- a/readthedocs/rtd_tests/tests/test_footer.py
+++ b/readthedocs/rtd_tests/tests/test_footer.py
@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 from django.contrib.sessions.backends.base import SessionBase
 from django.test import TestCase
 from django.test.utils import override_settings
diff --git a/readthedocs/rtd_tests/tests/test_imported_file.py b/readthedocs/rtd_tests/tests/test_imported_file.py
index db4f815b886..26323b81842 100644
--- a/readthedocs/rtd_tests/tests/test_imported_file.py
+++ b/readthedocs/rtd_tests/tests/test_imported_file.py
@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 
 import os
-import mock
+from unittest import mock
 
 from django.conf import settings
 from django.core.files.storage import get_storage_class
diff --git a/readthedocs/rtd_tests/tests/test_notifications.py b/readthedocs/rtd_tests/tests/test_notifications.py
index 9b41b9acbb1..afd19a00e9c 100644
--- a/readthedocs/rtd_tests/tests/test_notifications.py
+++ b/readthedocs/rtd_tests/tests/test_notifications.py
@@ -3,7 +3,7 @@
 
 
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.contrib.auth.models import AnonymousUser, User
 from django.http import HttpRequest
 from django.test import TestCase
diff --git a/readthedocs/rtd_tests/tests/test_oauth.py b/readthedocs/rtd_tests/tests/test_oauth.py
index e73382367dd..a536d67a1da 100644
--- a/readthedocs/rtd_tests/tests/test_oauth.py
+++ b/readthedocs/rtd_tests/tests/test_oauth.py
@@ -1,5 +1,5 @@
 # -*- coding: utf-8 -*-
-import mock
+from unittest import mock
 from django.conf import settings
 from django.contrib.auth.models import User
 from django.test import TestCase
diff --git a/readthedocs/rtd_tests/tests/test_oauth_tasks.py b/readthedocs/rtd_tests/tests/test_oauth_tasks.py
index 4378ed460a0..20cea96c2ec 100644
--- a/readthedocs/rtd_tests/tests/test_oauth_tasks.py
+++ b/readthedocs/rtd_tests/tests/test_oauth_tasks.py
@@ -7,7 +7,7 @@
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django_dynamic_fixture import get
-from mock import patch
+from unittest.mock import patch
 
 from readthedocs.builds.models import Version
 from readthedocs.oauth.services.base import SyncServiceError
diff --git a/readthedocs/rtd_tests/tests/test_privacy.py b/readthedocs/rtd_tests/tests/test_privacy.py
index 72d50e04cdb..098ac5dc7c0 100644
--- a/readthedocs/rtd_tests/tests/test_privacy.py
+++ b/readthedocs/rtd_tests/tests/test_privacy.py
@@ -1,6 +1,6 @@
 import logging
 
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django.test.utils import override_settings
diff --git a/readthedocs/rtd_tests/tests/test_privacy_urls.py b/readthedocs/rtd_tests/tests/test_privacy_urls.py
index cc01a2a477d..317db6e6dab 100644
--- a/readthedocs/rtd_tests/tests/test_privacy_urls.py
+++ b/readthedocs/rtd_tests/tests/test_privacy_urls.py
@@ -1,6 +1,6 @@
 import re
 
-import mock
+from unittest import mock
 from allauth.socialaccount.models import SocialAccount
 from django.contrib.admindocs.views import extract_views_from_urlpatterns
 from django.test import TestCase
diff --git a/readthedocs/rtd_tests/tests/test_project.py b/readthedocs/rtd_tests/tests/test_project.py
index e30f54237a3..2487252e67e 100644
--- a/readthedocs/rtd_tests/tests/test_project.py
+++ b/readthedocs/rtd_tests/tests/test_project.py
@@ -6,7 +6,7 @@
 from django.test import TestCase
 from django.utils import timezone
 from django_dynamic_fixture import get
-from mock import patch
+from unittest.mock import patch
 from rest_framework.reverse import reverse
 
 from readthedocs.builds.constants import (
diff --git a/readthedocs/rtd_tests/tests/test_project_forms.py b/readthedocs/rtd_tests/tests/test_project_forms.py
index 7638a8cbc4e..bfdfef99f41 100644
--- a/readthedocs/rtd_tests/tests/test_project_forms.py
+++ b/readthedocs/rtd_tests/tests/test_project_forms.py
@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django.test.utils import override_settings
diff --git a/readthedocs/rtd_tests/tests/test_project_symlinks.py b/readthedocs/rtd_tests/tests/test_project_symlinks.py
index c3efb16b191..a5c8acaef01 100644
--- a/readthedocs/rtd_tests/tests/test_project_symlinks.py
+++ b/readthedocs/rtd_tests/tests/test_project_symlinks.py
@@ -4,7 +4,7 @@
 import shutil
 import tempfile
 
-import mock
+from unittest import mock
 from django.conf import settings
 from django.test import TestCase, override_settings
 from django.urls import reverse
diff --git a/readthedocs/rtd_tests/tests/test_project_views.py b/readthedocs/rtd_tests/tests/test_project_views.py
index 9ca15e2e843..d1a203d517f 100644
--- a/readthedocs/rtd_tests/tests/test_project_views.py
+++ b/readthedocs/rtd_tests/tests/test_project_views.py
@@ -9,7 +9,7 @@
 from django.utils import timezone
 from django.views.generic.base import ContextMixin
 from django_dynamic_fixture import get, new
-from mock import patch
+from unittest.mock import patch
 
 from readthedocs.builds.constants import EXTERNAL, LATEST
 from readthedocs.builds.models import Build, Version
diff --git a/readthedocs/rtd_tests/tests/test_projects_tasks.py b/readthedocs/rtd_tests/tests/test_projects_tasks.py
index e02f851f2b1..612946f0159 100644
--- a/readthedocs/rtd_tests/tests/test_projects_tasks.py
+++ b/readthedocs/rtd_tests/tests/test_projects_tasks.py
@@ -2,7 +2,7 @@
 
 from django.test import TestCase
 from django_dynamic_fixture import get
-from mock import patch
+from unittest.mock import patch
 
 from readthedocs.builds.constants import EXTERNAL, BUILD_STATUS_SUCCESS
 from readthedocs.builds.models import Version, Build
diff --git a/readthedocs/rtd_tests/tests/test_resolver.py b/readthedocs/rtd_tests/tests/test_resolver.py
index 2620dbf095c..da9a1d1ad81 100644
--- a/readthedocs/rtd_tests/tests/test_resolver.py
+++ b/readthedocs/rtd_tests/tests/test_resolver.py
@@ -1,5 +1,5 @@
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.test import TestCase, override_settings
 
 from readthedocs.core.resolver import (
diff --git a/readthedocs/rtd_tests/tests/test_subprojects.py b/readthedocs/rtd_tests/tests/test_subprojects.py
index a86ad933683..21e81903d5b 100644
--- a/readthedocs/rtd_tests/tests/test_subprojects.py
+++ b/readthedocs/rtd_tests/tests/test_subprojects.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 import django_dynamic_fixture as fixture
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django.test.utils import override_settings
diff --git a/readthedocs/rtd_tests/tests/test_sync_versions.py b/readthedocs/rtd_tests/tests/test_sync_versions.py
index 1cce3165dd3..93ed8201b23 100644
--- a/readthedocs/rtd_tests/tests/test_sync_versions.py
+++ b/readthedocs/rtd_tests/tests/test_sync_versions.py
@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 
 import json
-import mock
+from unittest import mock
 
 from django.test import TestCase
 from django.urls import reverse
diff --git a/readthedocs/rtd_tests/tests/test_views.py b/readthedocs/rtd_tests/tests/test_views.py
index 3e820c207b4..d7bf77c310b 100644
--- a/readthedocs/rtd_tests/tests/test_views.py
+++ b/readthedocs/rtd_tests/tests/test_views.py
@@ -1,7 +1,7 @@
 import csv
 from urllib.parse import urlsplit
 
-import mock
+from unittest import mock
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django.urls import reverse
diff --git a/readthedocs/rtd_tests/tests/versions/test_admin_actions.py b/readthedocs/rtd_tests/tests/versions/test_admin_actions.py
index 03dbfd20039..e5a6e9737c7 100644
--- a/readthedocs/rtd_tests/tests/versions/test_admin_actions.py
+++ b/readthedocs/rtd_tests/tests/versions/test_admin_actions.py
@@ -1,9 +1,9 @@
 # -*- coding: utf-8 -*-
 
 import os
-import mock
+from unittest import mock
 
-from mock import call
+from unittest.mock import call
 import django_dynamic_fixture as fixture
 from django.test import TestCase
 from django.contrib.admin.helpers import ACTION_CHECKBOX_NAME
diff --git a/readthedocs/search/tests/test_search_tasks.py b/readthedocs/search/tests/test_search_tasks.py
index 86d2742ee67..75c01e35eeb 100644
--- a/readthedocs/search/tests/test_search_tasks.py
+++ b/readthedocs/search/tests/test_search_tasks.py
@@ -1,6 +1,6 @@
 """Tests for search tasks."""
 
-import mock
+from unittest import mock
 import pytest
 
 from django.urls import reverse
diff --git a/readthedocs/vcs_support/tests.py b/readthedocs/vcs_support/tests.py
index 0a271f52e7d..e604da9166f 100644
--- a/readthedocs/vcs_support/tests.py
+++ b/readthedocs/vcs_support/tests.py
@@ -3,7 +3,7 @@
 import shutil
 import unittest
 
-import mock
+from unittest import mock
 
 from readthedocs.vcs_support import utils
 
diff --git a/requirements/pip.txt b/requirements/pip.txt
index 9eab1c3d13e..5cb76e5c037 100644
--- a/requirements/pip.txt
+++ b/requirements/pip.txt
@@ -73,7 +73,6 @@ django-gravatar2==1.4.2
 pytz==2019.3
 Unipath==1.1
 django-kombu==0.9.4
-mock==3.0.5
 stripe==2.38.0
 regex==2019.11.1