diff --git a/pyproject.toml b/pyproject.toml
index d314186..6091a70 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -37,7 +37,7 @@ Changelog = "https://github.com/googleapis/langchain-google-firestore-python/blo
 
 [project.optional-dependencies]
 test = [
-    "black[jupyter]==26.1.0",
+    "black[jupyter]==26.3.1",
     "isort==8.0.0",
     "mypy==1.17.1",
     "pytest-asyncio==1.1.0",