diff --git a/.github/workflows/constraints.txt b/.github/workflows/constraints.txt
index 3796143..db79a4e 100644
--- a/.github/workflows/constraints.txt
+++ b/.github/workflows/constraints.txt
@@ -1,3 +1,3 @@
 pip==24.2
 poetry==1.8.3
-tox==4.18.0
+tox==4.21.0