diff --git a/tox.ini b/tox.ini
index 40c44c184..f81ac7ab0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,9 +9,6 @@ deps = -r{toxinidir}/requirements.txt
 install_command = pip install -U --allow-external pytidylib --allow-insecure pytidylib --allow-external netifaces --allow-insecure netifaces {opts} {packages}
 usedevelop = True
 setenv = VIRTUAL_ENV={envdir}
-         LANG=en_US.UTF-8
-         LANGUAGE=en_US:en
-         LC_ALL=C
          EVENTLET_NO_GREENDNS=yes
 commands =
    bash -x {toxinidir}/run-tests.sh {posargs}