diff --git a/tox.ini b/tox.ini
index 04183752a..6f23ec408 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,4 +1,5 @@
 [tox]
+minversion = 3.0
 envlist = py{27,36,37}-cov, htmlcov
 
 [testenv]