diff --git a/lambdas/letter-updates-transformer/package.json b/lambdas/letter-updates-transformer/package.json
index 73b69f1f0..ba5f096ac 100644
--- a/lambdas/letter-updates-transformer/package.json
+++ b/lambdas/letter-updates-transformer/package.json
@@ -8,7 +8,7 @@
     "@nhsdigital/nhs-notify-event-schemas-supplier-api": "*",
     "aws-embedded-metrics": "^4.2.1",
     "aws-lambda": "^1.0.7",
-    "esbuild": "0.27.2",
+    "esbuild": "0.28.1",
     "pino": "^10.3.0",
     "zod": "^4.1.13"
   },