diff --git a/tox.ini b/tox.ini
index 2cd7a3cb..deb1dd50 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,6 +3,7 @@ skipsdist = true
 envlist = py27,py34,py35
 
 [testenv]
+passenv = LC_ALL, LANG, HOME
 deps =
     binaryornot
     flake8