diff --git a/tests/runtests.py b/tests/runtests.py
index e5e9c18fca..b98a739249 100755
--- a/tests/runtests.py
+++ b/tests/runtests.py
@@ -99,8 +99,9 @@ class TestRunner:
         # Manually set INSTALLED_APPS to point to the test models.
         settings.INSTALLED_APPS = ALWAYS_INSTALLED_APPS + ['.'.join(a) for a in get_test_models()]
 
-        # Manually set DEBUG = False.
+        # Manually set DEBUG and USE_I18N.
         settings.DEBUG = False
+        settings.USE_I18N = True
 
         from django.db import connection
         from django.core import management