diff --git a/tox.ini b/tox.ini
index 5254fe90..4fbea41e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,7 +9,6 @@ deps=
 passenv=HTTP_PROXY HTTPS_PROXY http_proxy https_proxy NO_PROXY no_proxy
 setenv=
     VIRTUAL_ENV={envdir}
-basepython = python3.5
 usedevelop = True
 install_command = pip install {opts} {packages}
 whitelist_externals =
@@ -27,24 +26,29 @@ commands =
     stestr slowest
 
 [testenv:docs]
+basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 commands =
     rm -rf doc/build
     sphinx-build -W -b html doc/source doc/build/html
 
 [testenv:genconfig]
+basepython = python3
 commands =
     oslo-config-generator --config-file=etc/armada/config-generator.conf
 
 [testenv:genpolicy]
+basepython = python3
 commands =
     oslopolicy-sample-generator --config-file=etc/armada/policy-generator.conf
 
 [testenv:releasenotes]
+basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:pep8]
+basepython = python3
 deps =
     .[bandit]
     {[testenv]deps}
@@ -54,10 +58,12 @@ commands =
     bandit -r armada -x armada/tests -n 5
 
 [testenv:bandit]
+basepython = python3
 commands =
     bandit -r armada -x armada/tests -n 5
 
 [testenv:cover]
+basepython = python3
 setenv = {[testenv]setenv}
          PYTHON=coverage run --source armada --parallel-mode
 commands =