diff --git a/tox.ini b/tox.ini
index 8c55821..41fc126 100644
--- a/tox.ini
+++ b/tox.ini
@@ -16,12 +16,15 @@ commands =
 sitepackages = False
 
 [testenv:cover]
+basepython = python3
 commands = python setup.py testr --coverage --testr-args="{posargs}"
 
 [testenv:pep8]
+basepython = python3
 commands = flake8 {posargs}
 
 [testenv:venv]
+basepython = python3
 commands = {posargs}
 
 [flake8]