diff --git a/src/panels/calendar/dialog-calendar-event-editor.ts b/src/panels/calendar/dialog-calendar-event-editor.ts
index f8cb528300..b8808ae0c2 100644
--- a/src/panels/calendar/dialog-calendar-event-editor.ts
+++ b/src/panels/calendar/dialog-calendar-event-editor.ts
@@ -302,7 +302,11 @@ class DialogCalendarEventEditor extends LitElement {
     const duration = differenceInMilliseconds(this._dtend!, this._dtstart!);
 
     this._dtstart = new Date(
-      ev.detail.value + "T" + this._dtstart!.toISOString().split("T")[1]
+      ev.detail.value +
+        "T" +
+        this._dtstart!.toLocaleTimeString("en-GB", {
+          timeZone: this.hass.config.time_zone,
+        })
     );
 
     // Prevent that the end time can be before the start time. Try to keep the
@@ -326,7 +330,11 @@ class DialogCalendarEventEditor extends LitElement {
 
   private _endDateChanged(ev: CustomEvent) {
     this._dtend = new Date(
-      ev.detail.value + "T" + this._dtend!.toISOString().split("T")[1]
+      ev.detail.value +
+        "T" +
+        this._dtend!.toLocaleTimeString("en-GB", {
+          timeZone: this.hass.config.time_zone,
+        })
     );
   }
 
@@ -335,7 +343,11 @@ class DialogCalendarEventEditor extends LitElement {
     const duration = differenceInMilliseconds(this._dtend!, this._dtstart!);
 
     this._dtstart = new Date(
-      this._dtstart!.toISOString().split("T")[0] + "T" + ev.detail.value
+      this._dtstart!.toLocaleDateString("en-CA", {
+        timeZone: this.hass.config.time_zone,
+      }) +
+        "T" +
+        ev.detail.value
     );
 
     // Prevent that the end time can be before the start time. Try to keep the
@@ -357,7 +369,11 @@ class DialogCalendarEventEditor extends LitElement {
 
   private _endTimeChanged(ev: CustomEvent) {
     this._dtend = new Date(
-      this._dtend!.toISOString().split("T")[0] + "T" + ev.detail.value
+      this._dtend!.toLocaleDateString("en-CA", {
+        timeZone: this.hass.config.time_zone,
+      }) +
+        "T" +
+        ev.detail.value
     );
   }