diff --git a/tox.ini b/tox.ini
index 03c95b35b..bb4a84926 100644
--- a/tox.ini
+++ b/tox.ini
@@ -26,6 +26,7 @@ commands = stestr --test-path ./shade/tests/functional run --serial {posargs}
            stestr slowest
 
 [testenv:pep8]
+basepython = python3
 usedevelop = False
 skip_install = True
 deps =
@@ -38,15 +39,18 @@ commands =
     flake8 shade
 
 [testenv:venv]
+basepython = python3
 commands = {posargs}
 
 [testenv:debug]
+basepython = python3
 whitelist_externals = find
 commands =
     find . -type f -name "*.pyc" -delete
     oslo_debug_helper {posargs}
 
 [testenv:cover]
+basepython = python3
 setenv =
     {[testenv]setenv}
     PYTHON=coverage run --source shade --parallel-mode
@@ -57,6 +61,7 @@ commands =
     coverage xml -o cover/coverage.xml
 
 [testenv:ansible]
+basepython = python3
 # Need to pass some env vars for the Ansible playbooks
 passenv = HOME USER
 deps =
@@ -67,6 +72,7 @@ deps =
 commands = {toxinidir}/extras/run-ansible-tests.sh -e {envdir} {posargs}
 
 [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
@@ -75,6 +81,7 @@ commands =
   sphinx-build -W -d doc/build/doctrees -b html doc/source/ doc/build/html
 
 [testenv:releasenotes]
+basepython = python3
 skip_install = True
 deps =
     -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}