diff --git a/nanobot/cron/service.py b/nanobot/cron/service.py
index d1965a9..6fea4de 100644
--- a/nanobot/cron/service.py
+++ b/nanobot/cron/service.py
@@ -4,6 +4,7 @@ import asyncio
 import json
 import time
 import uuid
+from datetime import datetime
 from pathlib import Path
 from typing import Any, Callable, Coroutine
 
@@ -30,9 +31,18 @@ def _compute_next_run(schedule: CronSchedule, now_ms: int) -> int | None:
     if schedule.kind == "cron" and schedule.expr:
         try:
             from croniter import croniter
-            cron = croniter(schedule.expr, time.time())
-            next_time = cron.get_next()
-            return int(next_time * 1000)
+            from zoneinfo import ZoneInfo
+            base_time = time.time()
+            if schedule.tz:
+                tz = ZoneInfo(schedule.tz)
+                base_dt = datetime.fromtimestamp(base_time, tz=tz)
+                cron = croniter(schedule.expr, base_dt)
+                next_dt = cron.get_next(datetime)
+                return int(next_dt.timestamp() * 1000)
+            else:
+                cron = croniter(schedule.expr, base_time)
+                next_time = cron.get_next()
+                return int(next_time * 1000)
         except Exception:
             return None