diff --git a/tox.ini b/tox.ini
index d329c5d..b90454f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,7 +8,7 @@ basepython = python3
 allowlist_externals =
   rm
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+  -c{env:TOX_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
   -r{toxinidir}/test-requirements.txt
 commands = stestr run --slowest {posargs}
 
@@ -20,7 +20,7 @@ commands = {posargs}
 
 [testenv:docs]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+  -c{env:TOX_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -rf doc/build