diff --git a/requirements-dev.txt b/requirements-dev.txt
index e800855..3d724b0 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -4,4 +4,4 @@ isort==4.2.15
 py==1.4.34
 pytest==3.2.2
 pytest-django==3.1.2
-tox==2.8.2
+tox==2.9.1