diff --git a/tox.ini b/tox.ini
index f965d9f..2602e5e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,7 +10,7 @@ python =
   3.9: clean, py39, lint, typing
 
 [testenv]
-passenv = TOXENV CI
+passenv = TOXENV,CI
 whitelist_externals =
     true
 setenv =