diff --git a/tox.ini b/tox.ini
index be3f7e91..387ea9a9 100644
--- a/tox.ini
+++ b/tox.ini
@@ -34,13 +34,14 @@ deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 
 [testenv:pep8]
-basepython = python2.7
+basepython = python3
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands = flake8 {posargs} hooks unit_tests tests actions lib
            charm-proof
 
 [testenv:venv]
+basepython = python3
 commands = {posargs}
 
 [testenv:func27-noop]