diff --git a/requirements/test.txt b/requirements/test.txt
index 4b19f51..9a91ca4 100644
--- a/requirements/test.txt
+++ b/requirements/test.txt
@@ -1,7 +1,7 @@
 -r base.txt
 
 # Multi-environment testing
-tox ==2.9.1
+tox ==4.12.1
 
 # Wonderful py.test for testing
 pytest >=3.6.0