diff --git a/requirements/development.txt b/requirements/development.txt
index ad8df36..8f3033d 100644
--- a/requirements/development.txt
+++ b/requirements/development.txt
@@ -12,7 +12,7 @@ pyflakes==1.6.0
 mccabe==0.6.1
 pytest==3.1.3
 pytest-cov==2.5.1
-tox==2.7.0
+tox==2.9.1
 coveralls==1.2.0
 mock==2.0.0