diff --git a/django/core/management/commands/makemessages.py b/django/core/management/commands/makemessages.py
index 899775d020..0bc0e36679 100644
--- a/django/core/management/commands/makemessages.py
+++ b/django/core/management/commands/makemessages.py
@@ -356,7 +356,7 @@ class Command(NoArgsCommand):
         if domain == 'djangojs':
             extensions = handle_extensions(extensions or ['js'])
         else:
-            extensions = handle_extensions(extensions or ['html'])
+            extensions = handle_extensions(extensions or ['html', 'txt'])
 
         if verbosity > 1:
             sys.stdout.write('examining files with the extensions: %s\n'
diff --git a/docs/ref/django-admin.txt b/docs/ref/django-admin.txt
index 0b116f8c23..36b7bcda7c 100644
--- a/docs/ref/django-admin.txt
+++ b/docs/ref/django-admin.txt
@@ -417,7 +417,7 @@ Example usage::
 .. django-admin-option:: --extension
 
 Use the ``--extension`` or ``-e`` option to specify a list of file extensions
-to examine (default: ".html").
+to examine (default: ".html", ".txt").
 
 Example usage::
 
@@ -438,7 +438,7 @@ Example usage::
 Use the ``--domain`` or ``-d`` option to change the domain of the messages files.
 Currently supported:
 
-    * ``django`` for all ``*.py`` and ``*.html`` files (default)
+    * ``django`` for all ``*.py``, ``*.html`` and ``*.txt`` files (default)
     * ``djangojs`` for ``*.js`` files
 
 .. django-admin-option:: --symlinks
diff --git a/docs/topics/i18n/localization.txt b/docs/topics/i18n/localization.txt
index 4215201f35..a24db8d463 100644
--- a/docs/topics/i18n/localization.txt
+++ b/docs/topics/i18n/localization.txt
@@ -84,8 +84,9 @@ message file in the directory ``locale/LANG/LC_MESSAGES``. In the ``de``
 example, the file will be ``locale/de/LC_MESSAGES/django.po``.
 
 By default ``django-admin.py makemessages`` examines every file that has the
-``.html`` file extension. In case you want to override that default, use the
-``--extension`` or ``-e`` option to specify the file extensions to examine::
+``.html`` or ``.txt`` file extension. In case you want to override that
+default, use the ``--extension`` or ``-e`` option to specify the file
+extensions to examine::
 
     django-admin.py makemessages -l de -e txt