diff --git a/tox.ini b/tox.ini
index b2660bdba4..d3cafae531 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-minversion = 1.6
+minversion = 2.3
 envlist = py35,py27,pep8
 skipdist = True