diff --git a/tox.ini b/tox.ini
index 65960b0..3cc6a62 100644
--- a/tox.ini
+++ b/tox.ini
@@ -162,6 +162,7 @@
 commands = {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
@@ -172,6 +173,7 @@
 whitelist_externals = rm
 
 [testenv:pep8]
+basepython = python3
 commands =
     flake8 {posargs}
     check-uuid
@@ -196,6 +198,7 @@
 import-order-style = pep8
 
 [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