diff --git a/tox.ini b/tox.ini
index 95d83c2..b7c7a01 100644
--- a/tox.ini
+++ b/tox.ini
@@ -41,3 +41,10 @@ deps =
   pytest-freezegun
 commands =
   py.test {posargs:{env:JUNIT:} {env:COVERAGE:} {env:FLAKES:} tests/}
+
+[pytest]
+filterwarnings =
+  error
+  ignore:_SixMetaPathImporter:ImportWarning
+  ignore:Plural value:DeprecationWarning
+junit_family=xunit2