diff --git a/tox.ini b/tox.ini
index 2d15ebc..25866be 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,14 +6,14 @@ ignore_basepython_conflict = true
 [testenv]
 basepython = python3
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
 commands = stestr run --slowest {posargs}
 
 [testenv:pep8]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/test-requirements.txt
 commands =
   pre-commit run -a
@@ -51,7 +51,7 @@ import_exceptions =
 whitelist_externals =
   rm
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -rf releasenotes/build