diff --git a/build.gradle b/build.gradle
index 7fc33498b..655e81bd9 100644
--- a/build.gradle
+++ b/build.gradle
@@ -63,7 +63,7 @@ buildscript {
         notifications_core_build_download = 'https://ci.opensearch.org/ci/dbc/distribution-build-opensearch/' + opensearch_no_snapshot +
                 '/latest/linux/x64/tar/builds/opensearch/plugins/opensearch-notifications-core-' + notifications_no_snapshot + '.zip'
 
-        kotlin_version = System.getProperty("kotlin.version", "1.8.21")
+        kotlin_version = System.getProperty("kotlin.version", "1.9.25")
 
         security_plugin_version = System.getProperty("security.version", opensearch_build)
     }