diff --git a/addons/mail/static/src/core/common/thread_model.js b/addons/mail/static/src/core/common/thread_model.js
index aa676ad4439..846dbeaa60e 100644
--- a/addons/mail/static/src/core/common/thread_model.js
+++ b/addons/mail/static/src/core/common/thread_model.js
@@ -3,6 +3,7 @@
 import { ScrollPosition } from "@mail/core/common/scroll_position_model";
 import { createLocalId } from "@mail/utils/common/misc";
 
+import { deserializeDateTime } from "@web/core/l10n/dates";
 import { _t } from "@web/core/l10n/translation";
 import { Deferred } from "@web/core/utils/concurrency";
 
@@ -430,7 +431,7 @@ export class Thread {
         if (!this.last_interest_dt) {
             return undefined;
         }
-        return luxon.DateTime.fromISO(new Date(this.last_interest_dt).toISOString());
+        return deserializeDateTime(this.last_interest_dt);
     }
 
     /**