diff --git a/pyproject.toml b/pyproject.toml
index ad486f8..1e5ba2c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -66,7 +66,7 @@ dev-flake8 = [
   "pydoclint == 0.10.1",
   "pydocstyle == 6.3.0",
 ]
-dev-formatting = ["black == 26.5.1", "isort == 8.0.1"]
+dev-formatting = ["black == 26.5.1", "isort == 9.0.1"]
 dev-mkdocs = [
   "black == 26.5.1",
   "Markdown == 3.11",