diff --git a/tox.ini b/tox.ini
index d5a15bb9a..83fb3d91d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -103,7 +103,7 @@ commands = {envpython} -bb -m pytest {posargs:tests}
 # test envs with coverage
 
 [testenv:py35-pyqt59-cov]
-basepython = python3.6
+basepython = python3.5
 setenv =
     {[testenv]setenv}
     QUTE_BDD_WEBENGINE=true
@@ -116,7 +116,7 @@ commands =
     {envpython} scripts/dev/check_coverage.py {posargs}
 
 [testenv:py36-pyqt59-cov]
-basepython = python3.5
+basepython = python3.6
 setenv =
     {[testenv]setenv}
     QUTE_BDD_WEBENGINE=true