diff --git a/powerline/lib/file_watcher.py b/powerline/lib/file_watcher.py
index 426e168d..d2874c88 100644
--- a/powerline/lib/file_watcher.py
+++ b/powerline/lib/file_watcher.py
@@ -1,4 +1,4 @@
-# vim:fileencoding=UTF-8:noet
+# vim:fileencoding=utf-8:noet
 from __future__ import unicode_literals, absolute_import
 
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
diff --git a/powerline/lib/inotify.py b/powerline/lib/inotify.py
index 1b58d49a..9f247bca 100644
--- a/powerline/lib/inotify.py
+++ b/powerline/lib/inotify.py
@@ -1,4 +1,4 @@
-# vim:fileencoding=UTF-8:noet
+# vim:fileencoding=utf-8:noet
 from __future__ import unicode_literals, absolute_import
 
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
diff --git a/powerline/lib/tree_watcher.py b/powerline/lib/tree_watcher.py
index e345d286..c8568891 100644
--- a/powerline/lib/tree_watcher.py
+++ b/powerline/lib/tree_watcher.py
@@ -1,4 +1,4 @@
-# vim:fileencoding=UTF-8:noet
+# vim:fileencoding=utf-8:noet
 from __future__ import (unicode_literals, absolute_import, print_function)
 
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'