diff --git a/constraints.txt b/constraints.txt
index 08dbcb0c..8a36db2e 100644
--- a/constraints.txt
+++ b/constraints.txt
@@ -30,7 +30,7 @@ markdown-it-py==3.0.0
 MarkupSafe==3.0.3
 mdurl==0.1.2
 more-itertools==10.8.0
-nh3==0.3.0
+nh3==0.3.1
 packaging==25.0
 pluggy==1.6.0
 Pygments==2.19.2