diff --git a/tox.ini b/tox.ini
index 70b834d..d7d9ddd 100644
--- a/tox.ini
+++ b/tox.ini
@@ -15,12 +15,15 @@
   stestr slowest
 
 [testenv:pep8]
+basepython = python3
 commands = flake8 {posargs}
 
 [testenv:venv]
+basepython = python3
 commands = {posargs}
 
 [testenv:cover]
+basepython = python3
 setenv =
   {[testenv]setenv}
   PYTHON=coverage run --source octavia_tempest_plugin --parallel-mode
@@ -35,6 +38,7 @@
   coverage xml -o cover/coverage.xml
 
 [testenv:docs]
+basepython = python3
 deps =
     -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
     -r{toxinidir}/requirements.txt
@@ -45,6 +49,7 @@
   sphinx-build -W -b html doc/source doc/build/html
 
 [testenv:releasenotes]
+basepython = python3
 deps =
     -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
     -r{toxinidir}/requirements.txt
@@ -53,6 +58,7 @@
   sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:debug]
+basepython = python3
 commands = oslo_debug_helper {posargs}
 
 [flake8]
@@ -64,6 +70,7 @@
 exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build
 
 [testenv:genconfig]
+basepython = python3
 whitelist_externals = mkdir
 commands =
          mkdir -p etc