diff --git a/package.json b/package.json
index 83429b0..5be1108 100644
--- a/package.json
+++ b/package.json
@@ -35,7 +35,7 @@
     "@types/node": "^20.4.8",
     "@types/sinon": "^17.0.0",
     "c8": "^9.0.0",
-    "chai": "^4.2.0",
+    "chai": "^5.0.0",
     "codecov": "^3.0.4",
     "gts": "^5.0.0",
     "hard-rejection": "^2.1.0",
diff --git a/samples/package.json b/samples/package.json
index 8b7236e..7e23000 100644
--- a/samples/package.json
+++ b/samples/package.json
@@ -18,7 +18,7 @@
     "@google-cloud/promisify": "^4.0.0"
   },
   "devDependencies": {
-    "chai": "^4.2.0",
+    "chai": "^5.0.0",
     "mocha": "^8.0.0"
   }
 }