diff --git a/rules/prefer-await-to-then.js b/rules/prefer-await-to-then.js
index 09532477..1777c993 100644
--- a/rules/prefer-await-to-then.js
+++ b/rules/prefer-await-to-then.js
@@ -25,6 +25,7 @@ module.exports = {
             type: 'boolean',
           },
         },
+        additionalProperties: false,
       },
     ],
     messages: {