diff --git a/checker/standard_library.cc b/checker/standard_library.cc
index 744a171ef..182b64693 100644
--- a/checker/standard_library.cc
+++ b/checker/standard_library.cc
@@ -768,6 +768,9 @@ absl::Status AddTimeFunctions(TypeCheckerBuilder& builder) {
   get_seconds.set_name(StandardFunctions::kSeconds);
   CEL_RETURN_IF_ERROR(get_seconds.AddOverload(MakeMemberOverloadDecl(
       StandardOverloadIds::kTimestampToSeconds, IntType(), TimestampType())));
+  CEL_RETURN_IF_ERROR(get_seconds.AddOverload(
+      MakeMemberOverloadDecl(StandardOverloadIds::kTimestampToSecondsTz,
+                             IntType(), TimestampType(), StringType())));
   CEL_RETURN_IF_ERROR(get_seconds.AddOverload(
       MakeMemberOverloadDecl(StandardOverloadIds::kTimestampToSecondsWithTz,
                              IntType(), TimestampType(), StringType())));
diff --git a/common/standard_definitions.h b/common/standard_definitions.h
index eea185f6b..faa2802e8 100644
--- a/common/standard_definitions.h
+++ b/common/standard_definitions.h
@@ -287,8 +287,10 @@ struct StandardOverloadIds {
   static constexpr absl::string_view kDurationToMinutes = "duration_to_minutes";
   static constexpr absl::string_view kTimestampToSeconds =
       "timestamp_to_seconds";
-  static constexpr absl::string_view kTimestampToSecondsWithTz =
+  static constexpr absl::string_view kTimestampToSecondsTz =
       "timestamp_to_seconds_tz";
+  static constexpr absl::string_view kTimestampToSecondsWithTz =
+      "timestamp_to_seconds_with_tz";
   static constexpr absl::string_view kDurationToSeconds = "duration_to_seconds";
   static constexpr absl::string_view kTimestampToMilliseconds =
       "timestamp_to_milliseconds";