diff --git a/tox.ini b/tox.ini
index 262d643df0..db6f1031fb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,9 +9,7 @@ passenv=ZUUL_CACHE_DIR
 install_command = pip install -U {opts} {packages}
 setenv =
    VIRTUAL_ENV={envdir}
-# launchpadlib 0.0.1.dev533 requires lazr.restfulclient, which is
-# py2-only (as of lazr.restfulclient 0.13.1)
-basepython = python2.7
+basepython = python3
 deps = -r{toxinidir}/test-requirements.txt
 commands =
   python setup.py testr --coverage --testr-args='{posargs}'