diff --git a/tox.ini b/tox.ini
index 288b22c..aeef36b 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,6 +2,10 @@
 envlist = pep8,py36,py37,py38,py3-dj111
 minversion = 3.1
 skipsdist = True
+# Automatic envs (pyXX) will only use the python version appropriate to that
+# env and ignore basepython inherited from [testenv] if we set
+# ignore_basepython_conflict.
+ignore_basepython_conflict = True
 
 [testenv]
 basepython = python3