diff --git a/packages/lib/CalendarService.ts b/packages/lib/CalendarService.ts
index 295eaa22..503e5b82 100644
--- a/packages/lib/CalendarService.ts
+++ b/packages/lib/CalendarService.ts
@@ -248,12 +248,16 @@ export default abstract class BaseCalendarService implements Calendar {
         const vcalendar = new ICAL.Component(jcalData);
         const vevent = vcalendar.getFirstSubcomponent("vevent");
         const event = new ICAL.Event(vevent);
-        const timezoneComp = vcalendar.getFirstSubcomponent("vtimezone");
-        const tzid: string = timezoneComp?.getFirstPropertyValue("tzid") ?? "UTC";
+        const vtimezone = vcalendar.getFirstSubcomponent("vtimezone");
+        if (vtimezone) {
+          const zone = new ICAL.Timezone(vtimezone);
+          event.startDate = event.startDate.convertToZone(zone);
+          event.endDate = event.endDate.convertToZone(zone);
+        }
 
         return {
-          start: dayjs.tz(event.startDate.toJSDate(), tzid).toISOString(),
-          end: dayjs.tz(event.endDate.toJSDate(), tzid).toISOString(),
+          start: dayjs(event.startDate.toJSDate()).toISOString(),
+          end: dayjs(event.endDate.toJSDate()).toISOString(),
         };
       });