diff --git a/src/widgets/calendar/event.jsx b/src/widgets/calendar/event.jsx
index 91b40e82c..ac9dcb224 100644
--- a/src/widgets/calendar/event.jsx
+++ b/src/widgets/calendar/event.jsx
@@ -39,4 +39,5 @@ export default function Event({ event, colorVariants, showDate = false, showTime
     </div>
   );
 }
-export const compareDateTimezone = (date, event) => date.startOf("day").ts === event.date.startOf("day").ts;
+export const compareDateTimezone = (date, event) =>
+  date.startOf("day").toISODate() === event.date.startOf("day").toISODate();