diff --git a/pyproject.toml b/pyproject.toml
index 14d3ecd..b6b1ffe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -122,7 +122,7 @@ scientific = [
   "xarray<2025",
 ]
 test = [
-  "pytest<8",
+  "pytest<9",
   "pytest-cov<5",
   "pytest-timeout<3",
 ]