diff --git a/requirements.txt b/requirements.txt
index 7cf49ef6..4a7d25b9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,6 +8,6 @@ flake8==3.5.0
 
 # Testing
 # ------------------------------------------------------------------------------
-tox==3.2.1
+tox==3.4.0
 pytest==3.8.0
 pytest-cookies==0.3.0