diff --git a/src/types.ts b/src/types.ts
index a562b760a6..3044ca82e7 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -589,7 +589,7 @@ const datetimeRegex = (args: { precision: number | null; offset: boolean }) => {
         `^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}(([+-]\\d{2}(:?\\d{2})?)|Z)$`
       );
     } else {
-      return new RegExp(`^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}Z$`);
+      return new RegExp(`^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}Z?$`);
     }
   } else {
     if (args.offset) {