diff --git a/tox.ini b/tox.ini
index 1064cf54f956..9e6c1c65421d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -23,7 +23,7 @@ deps =
 basepython =
     python2.7
 commands =
-    nosetests --with-xunit --with-xcoverage --cover-package=gcloud --nocapture --cover-erase --cover-tests --cover-branches
+    nosetests --with-xunit --with-xcoverage --cover-package=gcloud --nocapture --cover-erase --cover-tests --cover-branches --cover-min-percentage=100
 deps =
     nose
     unittest2