diff --git a/tox.ini b/tox.ini
index 7ebe1935..33bb1dab 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,9 +6,6 @@ skipsdist = True
 [testenv]
 setenv =
    VIRTUAL_ENV={envdir}
-   LANG=en_US.UTF-8
-   LANGUAGE=en_US:en
-   LC_ALL=C
 deps = -r{toxinidir}/test-requirements.txt
 
 [testenv:venv]