diff --git a/assets/admin/components/BlogSeoFields.tsx b/assets/admin/components/BlogSeoFields.tsx
index fbfc9db6..2a30fda3 100644
--- a/assets/admin/components/BlogSeoFields.tsx
+++ b/assets/admin/components/BlogSeoFields.tsx
@@ -2,6 +2,7 @@ import { Controller, useFieldArray } from 'react-hook-form';
 import type { Control, UseFormRegister } from 'react-hook-form';
 import type { BlogFormData } from '../lib/blogForm';
 import PersianDatePicker from './ui/PersianDatePicker';
+import { toGregorianDate, toTehranClockTime, tehranWallClockToUnix } from '../lib/utils';
 
 interface Props {
     control: Control<BlogFormData>;
@@ -90,16 +91,16 @@ export default function BlogSeoFields({ control, register }: Props) {
     );
 }
 
-/** Gregorian date + time → unix seconds, and back. */
+/** Gregorian date + time → unix seconds, and back — همیشه به وقت ایران. */
 function ScheduleField({ value, onChange }: { value: number | null; onChange: (v: number | null) => void }) {
     const d = value ? new Date(value * 1000) : null;
-    const dateStr = d ? d.toISOString().slice(0, 10) : '';
-    const timeStr = d ? d.toTimeString().slice(0, 5) : '00:00';
+    const dateStr = d ? toGregorianDate(d) : '';
+    const timeStr = d ? toTehranClockTime(d) : '00:00';
 
     const emit = (nextDate: string, nextTime: string) => {
         if (!nextDate) return onChange(null);
-        const ms = Date.parse(`${nextDate}T${nextTime || '00:00'}:00`);
-        onChange(Number.isNaN(ms) ? null : Math.floor(ms / 1000));
+        const ts = tehranWallClockToUnix(nextDate, nextTime || '00:00');
+        onChange(Number.isNaN(ts) ? null : ts);
     };
 
     return (
diff --git a/assets/admin/components/schedule/ScheduleSection.tsx b/assets/admin/components/schedule/ScheduleSection.tsx
index 91efd49d..9793b46f 100644
--- a/assets/admin/components/schedule/ScheduleSection.tsx
+++ b/assets/admin/components/schedule/ScheduleSection.tsx
@@ -10,7 +10,7 @@ import {
 import { toast } from 'sonner';
 import { api, ApiError } from '../../lib/api';
 import type { ApiResponse } from '../../lib/api';
-import { formatNumber, digitsOnly } from '../../lib/utils';
+import { formatNumber, digitsOnly, todayIso, unixToIso } from '../../lib/utils';
 import Modal from '../ui/Modal';
 import ConfirmDialog from '../ui/ConfirmDialog';
 import GlobalSearchableSelect from '../ui/SearchableSelect';
@@ -37,8 +37,10 @@ export interface AddressData {
 // ── Schedule types ─────────────────────────────────────────────────────────
 
 interface SlotConfig       { start: string; end: string; duration: number; }
-interface DateOverrideData   { uuid: string; doctor_uuid: string; date: number; active: boolean; reason: string | null; custom_slots: SessionConfig[]; }
-interface HolidayData        { uuid: string; doctor_uuid: string; start_date: number; end_date: number; active: boolean; reason: string | null; }
+// `*_string` فیلدهای «Y-m-d» سرور هستند؛ برای نمایش همیشه اولویت با آن‌هاست تا
+// تبدیل timestamp در مرورگر تاریخ را یک روز جابه‌جا نکند.
+interface DateOverrideData   { uuid: string; doctor_uuid: string; date: number; date_string?: string; active: boolean; reason: string | null; custom_slots: SessionConfig[]; }
+interface HolidayData        { uuid: string; doctor_uuid: string; start_date: number; end_date: number; start_date_string?: string; end_date_string?: string; active: boolean; reason: string | null; }
 
 interface SessionConfig {
   active: boolean;
@@ -109,7 +111,7 @@ function jFirstDayOfWeek(jy: number, jm: number): number {
   const dow = new Date(gy, gm - 1, gd).getDay(); // 0=Sunday
   return (dow + 1) % 7; // 0=Saturday, 1=Sunday, ..., 6=Friday
 }
-function todayGregorian(): string { return new Date().toISOString().slice(0, 10); }
+function todayGregorian(): string { return todayIso(); }
 
 // ── Persian Date Picker ────────────────────────────────────────────────────
 
@@ -285,7 +287,11 @@ function calcSlotCount(session: SessionConfig): number {
   return count;
 }
 function tsToDate(ts: number): string {
-  return new Date(ts * 1000).toISOString().slice(0, 10);
+  return unixToIso(ts);
+}
+/** رشتهٔ `Y-m-d` سرور در اولویت است؛ timestamp فقط fallback رکوردهای قدیمی پاسخ است. */
+function dayString(serverString: string | undefined, ts: number): string {
+  return serverString || tsToDate(ts);
 }
 
 // ── Schedule components ────────────────────────────────────────────────────
@@ -925,12 +931,12 @@ function DateOverrideModal({ open, onClose, existing, doctorUuid, clinicUuid, on
   useEffect(() => {
     if (open) {
       if (existing) {
-        setDateStr(tsToDate(existing.date));
+        setDateStr(dayString(existing.date_string, existing.date));
         setOverrideType(existing.active ? 'custom' : 'closed');
         setReason(existing.reason ?? '');
         setSlots((existing.custom_slots ?? []).map(toSession));
       } else {
-        setDateStr(new Date().toISOString().slice(0, 10));
+        setDateStr(todayGregorian());
         setOverrideType('closed'); setReason(''); setSlots([]);
       }
     }
@@ -1088,7 +1094,7 @@ function DateOverridesTab({ doctorUuid, clinicUuid, addresses, readOnly = false
             <div key={ov.uuid} className="flex items-center gap-3 p-3.5 rounded-xl border border-[var(--border)] bg-[var(--surface)]">
               <div className="flex-1 min-w-0">
                 <div className="flex items-center gap-2 flex-wrap">
-                  <span className="text-sm font-medium text-[var(--text)]">{formatPersianDate(tsToDate(ov.date))}</span>
+                  <span className="text-sm font-medium text-[var(--text)]">{formatPersianDate(dayString(ov.date_string, ov.date))}</span>
                   {ov.active ? (
                     <span className="text-xs px-2 py-0.5 rounded-full font-medium bg-[var(--warning-bg)] text-[var(--warning)]">
                       {ov.custom_slots.length > 0 ? `${ov.custom_slots.length} بازه سفارشی` : 'ساعات خاص'}
@@ -1141,11 +1147,11 @@ function HolidayModal({ open, onClose, existing, doctorUuid, clinicUuid, onSaved
   useEffect(() => {
     if (open) {
       if (existing) {
-        setStartDate(tsToDate(existing.start_date));
-        setEndDate(tsToDate(existing.end_date));
+        setStartDate(dayString(existing.start_date_string, existing.start_date));
+        setEndDate(dayString(existing.end_date_string, existing.end_date));
         setReason(existing.reason ?? '');
       } else {
-        const today = new Date().toISOString().slice(0, 10);
+        const today = todayGregorian();
         setStartDate(today); setEndDate(today); setReason('');
       }
     }
@@ -1254,13 +1260,15 @@ function HolidaysTab({ doctorUuid, clinicUuid, readOnly = false }: { doctorUuid:
             const now       = Math.floor(Date.now() / 1000);
             const isPast    = h.end_date < now;
             const isCurrent = h.start_date <= now && h.end_date >= now;
-            const sameDay   = tsToDate(h.start_date) === tsToDate(h.end_date);
+            const startDay  = dayString(h.start_date_string, h.start_date);
+            const endDay    = dayString(h.end_date_string,   h.end_date);
+            const sameDay   = startDay === endDay;
             return (
               <div key={h.uuid} className={`flex items-center gap-3 p-3.5 rounded-xl border transition-colors ${isCurrent ? 'border-[var(--danger)] bg-[var(--danger-bg)]/40' : isPast ? 'border-[var(--border)] bg-[var(--surface-2)]/40 opacity-70' : 'border-[var(--accent)] bg-[var(--accent-bg)]/30'}`}>
                 <div className="flex-1 min-w-0">
                   <div className="flex items-center gap-2 flex-wrap">
                     <span className={`text-sm font-medium ${isPast ? 'text-[var(--text-2)]' : 'text-[var(--text)]'}`}>
-                      {sameDay ? formatPersianDate(tsToDate(h.start_date)) : `${formatPersianDate(tsToDate(h.start_date))} تا ${formatPersianDate(tsToDate(h.end_date))}`}
+                      {sameDay ? formatPersianDate(startDay) : `${formatPersianDate(startDay)} تا ${formatPersianDate(endDay)}`}
                     </span>
                     {isCurrent && h.active && (
                       <span className="text-xs px-2 py-0.5 rounded-full font-medium bg-[var(--danger-bg)] text-[var(--danger)] animate-pulse">در جریان</span>
diff --git a/assets/admin/components/session/CreateStep.tsx b/assets/admin/components/session/CreateStep.tsx
index 4ad07c11..aa8274c4 100644
--- a/assets/admin/components/session/CreateStep.tsx
+++ b/assets/admin/components/session/CreateStep.tsx
@@ -10,7 +10,7 @@ import SearchableSelect from '../ui/SearchableSelect';
 import PersianDateInput from '../ui/PersianDateInput';
 import { UserTick, FilesServiceAddCard, ClockP, TrashRed } from '../icons/FilesServiceIcons';
 import { useAuthStore } from '../../stores/authStore';
-import { digitsOnly } from '../../lib/utils';
+import { digitsOnly, todayIso } from '../../lib/utils';
 import {
   DEFAULT_SERVICE_CATEGORY, contractPercentFor, patientShareOf,
   type CoverageRule as Rule, type TenantContract,
@@ -29,7 +29,7 @@ const VISIT_SERVICE_CATEGORY = DEFAULT_SERVICE_CATEGORY;
 // مصرف‌کنندگان قبلی (و تست‌ها) نشکنند.
 export { patientShareOf };
 
-const todayISO = () => new Date().toISOString().slice(0, 10);
+const todayISO = todayIso;
 const nowHHMM = () => {
   const d = new Date();
   return `${String(d.getHours()).padStart(2, '0')}:${String(d.getMinutes()).padStart(2, '0')}`;
diff --git a/assets/admin/components/session/PaymentStep.tsx b/assets/admin/components/session/PaymentStep.tsx
index fa2386da..37748579 100644
--- a/assets/admin/components/session/PaymentStep.tsx
+++ b/assets/admin/components/session/PaymentStep.tsx
@@ -5,7 +5,7 @@ import { toast } from 'sonner';
 import { api } from '../../lib/api';
 import type { ApiResponse } from '../../lib/api';
 import { PencilIcon, TrashIcon } from '@heroicons/react/24/outline';
-import { formatRial, formatDateTime, tomanToRial, rialToToman } from '../../lib/utils';
+import { formatRial, formatDateTime, tomanToRial, rialToToman, todayIso } from '../../lib/utils';
 import type { DiscountSuggestion } from '../../types';
 import type { SessionCardData } from '../SessionServiceCard';
 import SearchableSelect from '../ui/SearchableSelect';
@@ -26,7 +26,7 @@ export const METHOD_LABELS: Record<string, string> = {
   wallet: 'پرداخت از کیف پول', pos: 'پرداخت کارتخوان', cash: 'پرداخت نقدی', card: 'کارت به کارت',
 };
 
-const todayISO = () => new Date().toISOString().slice(0, 10);
+const todayISO = todayIso;
 /** YYYY-MM-DD → unix (ظهر همان روز تا با هر timezone یک روز بماند) */
 const isoToUnix = (iso: string) => Math.floor(new Date(`${iso}T12:00:00`).getTime() / 1000);
 
diff --git a/assets/admin/components/ui/PersianCalendar.tsx b/assets/admin/components/ui/PersianCalendar.tsx
index f1d9f225..fcaab4bc 100644
--- a/assets/admin/components/ui/PersianCalendar.tsx
+++ b/assets/admin/components/ui/PersianCalendar.tsx
@@ -1,5 +1,6 @@
 import React, { useEffect, useRef, useState } from 'react';
 import { ChevronRightIcon, ChevronLeftIcon } from '@heroicons/react/24/outline';
+import { todayIso } from '../../lib/utils';
 
 interface Props {
   value: string;        // YYYY-MM-DD Gregorian
@@ -70,7 +71,8 @@ const JALALI_MONTHS = ['فروردین','اردیبهشت','خرداد','تیر'
 export default function PersianCalendar({ value, onChange, onClose, enableYearPicker = false }: Props) {
   const ref = useRef<HTMLDivElement>(null);
 
-  const todayGreg = new Date().toISOString().slice(0, 10);
+  // «امروز» به وقت ایران، نه UTC: `toISOString` بعد از ۲۰:۳۰ فردا را امروز نشان می‌داد.
+  const todayGreg = todayIso();
   const todayJ = toJalali(new Date(todayGreg + 'T12:00:00'));
   const valueJ = value ? toJalali(new Date(value + 'T12:00:00')) : todayJ;
 
diff --git a/assets/admin/lib/patientForm.test.ts b/assets/admin/lib/patientForm.test.ts
index 3c9346f4..97600730 100644
--- a/assets/admin/lib/patientForm.test.ts
+++ b/assets/admin/lib/patientForm.test.ts
@@ -9,11 +9,16 @@ import type { PatientProfile } from '@/types';
 import type { PatientFormValues } from '@/components/PatientRecordInfoForm';
 
 describe('date helpers', () => {
-    it('timestamp ↔ YYYY-MM-DD رفت‌وبرگشت', () => {
+    // مبنا نیمه‌شبِ تهران است (نه UTC)، چون بک‌اند هم تاریخ‌های روزمحور را با
+    // strtotime در تایم‌زون سرور (Asia/Tehran) ذخیره می‌کند.
+    it('timestamp ↔ YYYY-MM-DD رفت‌وبرگشت روی نیمه‌شبِ تهران', () => {
         const ts = dateStrToTs('2025-01-07');
-        expect(ts).toBe(Math.floor(Date.parse('2025-01-07T00:00:00Z') / 1000));
+        expect(ts).toBe(Math.floor(Date.UTC(2025, 0, 6, 20, 30, 0) / 1000));
         expect(tsToDateStr(ts)).toBe('2025-01-07');
     });
+    it('timestampهای ساخته‌شده توسط سرور یک روز عقب نمی‌روند', () => {
+        expect(tsToDateStr(Math.floor(Date.UTC(2026, 6, 28, 20, 30, 0) / 1000))).toBe('2026-07-29');
+    });
     it('خالی/نامعتبر → مقدار تهی', () => {
         expect(tsToDateStr(null)).toBe('');
         expect(tsToDateStr(0)).toBe('');
diff --git a/assets/admin/lib/patientForm.ts b/assets/admin/lib/patientForm.ts
index 7a4ef0e7..1abaca9d 100644
--- a/assets/admin/lib/patientForm.ts
+++ b/assets/admin/lib/patientForm.ts
@@ -1,6 +1,7 @@
 import type { SelectOption } from '../components/ui/SearchableSelect';
 import type { PatientProfile, PatientProfileUpdate } from '../types';
 import type { PatientFormValues } from '../components/PatientRecordInfoForm';
+import { unixToIso, tehranWallClockToUnix } from './utils';
 
 // ── enumهای ثابت فرم «اطلاعات پرونده» (بدون منبع API) ─────────────────────────
 export const GENDER_OPTS: SelectOption[] = [
@@ -21,14 +22,15 @@ export const REFERRAL_OPTS: SelectOption[] = [
 ].map((v) => ({ value: v, label: v }));
 
 // ── تبدیل تاریخ: timestamp ثانیه‌ای ↔ رشتهٔ میلادی YYYY-MM-DD ─────────────────
+// هر دو سمت به وقت ایران‌اند تا با نیمه‌شبِ محلیِ ذخیره‌شده در بک‌اند هم‌راستا باشند؛
+// تبدیل UTC روز را یک واحد جابه‌جا می‌کرد.
 export function tsToDateStr(ts?: number | null): string {
-  if (!ts) return '';
-  return new Date(ts * 1000).toISOString().slice(0, 10);
+  return ts ? unixToIso(ts) : '';
 }
 export function dateStrToTs(s: string): number | null {
   if (!s) return null;
-  const t = Date.parse(`${s}T00:00:00Z`);
-  return Number.isNaN(t) ? null : Math.floor(t / 1000);
+  const t = tehranWallClockToUnix(s, '00:00');
+  return Number.isNaN(t) ? null : t;
 }
 
 /** پروفایل API → مقادیر پیش‌فرض فرم. */
diff --git a/assets/admin/lib/utils.test.ts b/assets/admin/lib/utils.test.ts
index 277b93dd..9c6fc3d9 100644
--- a/assets/admin/lib/utils.test.ts
+++ b/assets/admin/lib/utils.test.ts
@@ -16,6 +16,10 @@ import {
     formatDate,
     formatDateTime,
     toGregorianDate,
+    toTehranClockTime,
+    tehranWallClockToUnix,
+    unixToIso,
+    todayIso,
     maskMobile,
     cn,
     toEnglishDigits,
@@ -107,6 +111,42 @@ describe('toGregorianDate', () => {
     });
 });
 
+describe('unixToIso / todayIso / toTehranClockTime', () => {
+    // نیمه‌شبِ ۲۹ ژوئیهٔ ۲۰۲۶ به وقت تهران = ۲۸ ژوئیه ۲۰:۳۰ UTC. تبدیل با
+    // toISOString همین‌جا یک روز عقب می‌رفت — رگرسیونِ «تاریخ خاص یک روز قبل».
+    const tehranMidnight = Math.floor(Date.UTC(2026, 6, 28, 20, 30, 0) / 1000);
+
+    it('timestamp نیمه‌شبِ تهران همان روز را می‌دهد، نه روز قبل', () => {
+        expect(unixToIso(tehranMidnight)).toBe('2026-07-29');
+    });
+
+    it('لحظهٔ آخر شب به وقت تهران هنوز همان روز است', () => {
+        const lateNight = Math.floor(Date.UTC(2026, 6, 29, 20, 0, 0) / 1000); // ۲۳:۳۰ تهران
+        expect(unixToIso(lateNight)).toBe('2026-07-29');
+    });
+
+    it('مقدار خالی رشتهٔ تهی می‌دهد', () => {
+        expect(unixToIso(null)).toBe('');
+        expect(unixToIso(undefined)).toBe('');
+    });
+
+    it('todayIso همان تاریخ تهرانِ لحظهٔ جاری است', () => {
+        expect(todayIso()).toBe(toGregorianDate(new Date()));
+        expect(todayIso()).toMatch(/^\d{4}-\d{2}-\d{2}$/);
+    });
+
+    it('ساعت دیواری تهران با رقم لاتین و ۲۴ساعته برمی‌گردد', () => {
+        expect(toTehranClockTime(new Date(tehranMidnight * 1000))).toBe('00:00');
+        expect(toTehranClockTime(new Date(Date.UTC(2026, 6, 29, 10, 0, 0)))).toBe('13:30');
+    });
+
+    it('رفت‌وبرگشتِ tehranWallClockToUnix ↔ unixToIso روز را جابه‌جا نمی‌کند', () => {
+        const ts = tehranWallClockToUnix('2026-07-29', '00:00');
+        expect(ts).toBe(tehranMidnight);
+        expect(unixToIso(ts)).toBe('2026-07-29');
+    });
+});
+
 describe('maskMobile', () => {
     it('شماره ۱۱ رقمی را ماسک می‌کند', () => {
         expect(maskMobile('09123456789')).toBe('0912***789');
diff --git a/assets/admin/lib/utils.ts b/assets/admin/lib/utils.ts
index 80159e85..eb4accba 100644
--- a/assets/admin/lib/utils.ts
+++ b/assets/admin/lib/utils.ts
@@ -87,6 +87,14 @@ export function toGregorianDate(d: Date): string {
   }).format(d);
 }
 
+// ساعت دیواریِ ایران به صورت «HH:MM» با رقم لاتین — برای مقداردهی <input type="time">
+// (بر خلاف formatTime که رقم فارسی می‌دهد و در input معتبر نیست).
+export function toTehranClockTime(d: Date): string {
+  return new Intl.DateTimeFormat('en-GB', {
+    timeZone: APP_TZ, hour12: false, hour: '2-digit', minute: '2-digit',
+  }).format(d);
+}
+
 // API stores contract dates as Unix seconds; the date input speaks Y-m-d strings.
 export function isoToUnix(iso: string): number | null {
   const d = toDate(iso);
@@ -98,6 +106,12 @@ export function unixToIso(ts: number | null | undefined): string {
   return toGregorianDate(new Date(ts * 1000));
 }
 
+// «امروز» به وقت ایران. هرگز از `new Date().toISOString().slice(0,10)` استفاده نکن؛
+// آن تاریخِ UTC است و بعد از ۲۰:۳۰ به‌وقت تهران یک روز جلو می‌افتد.
+export function todayIso(): string {
+  return toGregorianDate(new Date());
+}
+
 // عنوان «دکتر» فقط در نمایش افزوده می‌شود و هرگز در فیلد name دیتابیس ذخیره نمی‌شود
 // (backend با stripDoctorTitle حذف می‌کند). این helper تنها نقطهٔ افزودن عنوان است تا
 // در کل پنل یکسان باشد و از «دکتر دکتر …» یا نمایش بدون عنوان جلوگیری شود.
diff --git a/assets/admin/pages/AppointmentCreatePage.tsx b/assets/admin/pages/AppointmentCreatePage.tsx
index 00946c24..196357ef 100644
--- a/assets/admin/pages/AppointmentCreatePage.tsx
+++ b/assets/admin/pages/AppointmentCreatePage.tsx
@@ -14,7 +14,7 @@ import { WalletChargeLink } from '../components/AppointmentActions';
 import { useDoctorBookingServices } from '../hooks/useDoctorBookingServices';
 import ServiceSlotPicker from '../components/appointments/ServiceSlotPicker';
 import { tehranWallClockToUnix, rialToToman, tomanToRial } from '../lib/utils';
-import { digitsOnly } from '../lib/utils';
+import { digitsOnly, todayIso } from '../lib/utils';
 
 /**
  * افزودن نوبت — صفحهٔ کامل (بازسازی `CreateTurn.jsx` طرح tauri). از همان endpointهای
@@ -43,7 +43,7 @@ export default function AppointmentCreatePage() {
   const dbUuid = useAuthStore(s => s.dbUuid);
   const isDoctor = primaryRole === 'doctor';
 
-  const today = new Date().toISOString().slice(0, 10);
+  const today = todayIso();
 
   // ── پزشک
   const [doctorUuid, setDoctorUuid] = useState(isDoctor && dbUuid ? dbUuid : (params.get('doctor') ?? ''));
diff --git a/assets/admin/pages/AppointmentsPage.tsx b/assets/admin/pages/AppointmentsPage.tsx
index 95e01205..0b5d16b9 100644
--- a/assets/admin/pages/AppointmentsPage.tsx
+++ b/assets/admin/pages/AppointmentsPage.tsx
@@ -9,7 +9,7 @@ import { toast } from 'sonner';
 import { api } from '../lib/api';
 import type { PaginatedResponse, ApiResponse } from '../lib/api';
 import type { Appointment } from '../types';
-import { formatDate, toGregorianDate, formatTime, digitsOnly, sanitizeMobileInput, rialToToman, tomanToRial, formatRial } from '../lib/utils';
+import { formatDate, toGregorianDate, todayIso, formatTime, digitsOnly, sanitizeMobileInput, rialToToman, tomanToRial, formatRial } from '../lib/utils';
 import PriceInput from '../components/ui/PriceInput';
 import Modal from '../components/ui/Modal';
 import { useAuthStore } from '../stores/authStore';
@@ -507,7 +507,7 @@ export default function AppointmentsPage() {
   const canCancelAppt = can('appointments', 'cancel');
 
   const [params] = useSearchParams();
-  const today = new Date().toISOString().slice(0, 10);
+  const today = todayIso();
   // پس از ویرایش/ثبت، صفحه با ?date=... باز می‌شود تا همان روز نمایش داده شود.
   const [selectedDate, setSelectedDate] = useState(params.get('date') || today);
   const [viewMode, setViewMode] = useState<TurnsViewMode>('timeline');
diff --git a/assets/admin/pages/ClaimsPage.tsx b/assets/admin/pages/ClaimsPage.tsx
index 6c69938e..abc6b3d4 100644
--- a/assets/admin/pages/ClaimsPage.tsx
+++ b/assets/admin/pages/ClaimsPage.tsx
@@ -3,7 +3,7 @@ import { useQuery } from '@tanstack/react-query';
 import { useNavigate, useSearchParams } from 'react-router-dom';
 import { ArrowPathIcon } from '@heroicons/react/24/outline';
 import { api } from '../lib/api';
-import { formatRial, formatNumber } from '../lib/utils';
+import { formatRial, formatNumber, toGregorianDate, todayIso } from '../lib/utils';
 import type { ClaimPatientRow } from '../types';
 import type { ApiResponse, PaginatedResponse } from '../lib/api';
 import PageHeader from '../components/ui/PageHeader';
@@ -35,9 +35,8 @@ const PAYMENT_OPTIONS = [
 const isoNDaysAgo = (days: number): string => {
   const d = new Date();
   d.setDate(d.getDate() - days);
-  return d.toISOString().slice(0, 10);
+  return toGregorianDate(d);
 };
-const todayIso = (): string => new Date().toISOString().slice(0, 10);
 
 const toUnix = (iso: string): number | null => {
   if (!iso) return null;
diff --git a/assets/admin/pages/MyPaymentsPage.tsx b/assets/admin/pages/MyPaymentsPage.tsx
index b6cbc8ac..d79d5d29 100644
--- a/assets/admin/pages/MyPaymentsPage.tsx
+++ b/assets/admin/pages/MyPaymentsPage.tsx
@@ -7,7 +7,7 @@ import SearchableSelect from '../components/ui/SearchableSelect';
 import StatCard from '../components/ui/StatCard';
 import StatusBadge from '../components/ui/StatusBadge';
 import DataTable, { type Column } from '../components/ui/DataTable';
-import { formatRial, formatDate, formatNumber, toDate } from '../lib/utils';
+import { formatRial, formatDate, formatNumber, toDate, toGregorianDate, todayIso } from '../lib/utils';
 import {
   usePayments,
   usePaymentsSummary,
@@ -25,9 +25,8 @@ const STATUS_OPTIONS = [
 const isoNDaysAgo = (days: number): string => {
   const d = new Date();
   d.setDate(d.getDate() - days);
-  return d.toISOString().slice(0, 10);
+  return toGregorianDate(d);
 };
-const todayIso = (): string => new Date().toISOString().slice(0, 10);
 
 /** HH:MM (Persian digits) from a unix timestamp. */
 function formatTime(unix: number): string {
diff --git a/assets/admin/pages/PatientDetailPage.tsx b/assets/admin/pages/PatientDetailPage.tsx
index 449e7602..20a3e4ce 100644
--- a/assets/admin/pages/PatientDetailPage.tsx
+++ b/assets/admin/pages/PatientDetailPage.tsx
@@ -13,7 +13,7 @@ import { api } from '../lib/api';
 import type { ApiResponse } from '../lib/api';
 import type { PatientRecord } from '../types';
 import { useAuthStore } from '../stores/authStore';
-import { formatDate, formatDateTime, formatRial, formatTime, formatNumber } from '../lib/utils';
+import { formatDate, formatDateTime, formatRial, formatTime, formatNumber, unixToIso } from '../lib/utils';
 import DataTable, { type Column } from '../components/ui/DataTable';
 import type { WalletTxn } from '../hooks/usePatientWallet';
 import type { WalletModalSubmit } from '../components/WalletTransactionModal';
@@ -390,7 +390,7 @@ function MedicalRecordsTab({ uuid }: { uuid: string }) {
 
   const open = (m?: MedicalItem) => {
     setTitle(m?.title ?? ''); setBody(m?.body ?? '');
-    setDate(m?.recorded_at ? new Date(m.recorded_at * 1000).toISOString().slice(0, 10) : '');
+    setDate(unixToIso(m?.recorded_at));
     setModal(m ?? 'create');
   };
 
diff --git a/assets/admin/pages/PatientRecordFormPage.tsx b/assets/admin/pages/PatientRecordFormPage.tsx
index b186bed0..40c40e0a 100644
--- a/assets/admin/pages/PatientRecordFormPage.tsx
+++ b/assets/admin/pages/PatientRecordFormPage.tsx
@@ -12,7 +12,7 @@ import type { PatientRecord } from '../types';
 import PersianDateInput from '../components/ui/PersianDateInput';
 import SearchableSelect from '../components/ui/SearchableSelect';
 import { numericField } from '../lib/forms';
-import { iranNationalCodeSchema, iranMobileSchema } from '../lib/utils';
+import { iranNationalCodeSchema, iranMobileSchema, unixToIso } from '../lib/utils';
 
 const REFERRAL_OPTIONS = ['اینستاگرام', 'معرفی دوستان و آشنایان', 'جستجوی اینترنتی', 'تابلو مطب', 'سایر'];
 
@@ -29,7 +29,7 @@ const schema = z.object({
 type Form = z.infer<typeof schema>;
 
 const toEpoch = (iso?: string) => (iso ? Math.floor(new Date(iso).getTime() / 1000) : null);
-const fromEpoch = (ts?: number | null) => (ts ? new Date(ts * 1000).toISOString().slice(0, 10) : '');
+const fromEpoch = (ts?: number | null) => unixToIso(ts);
 
 /** تشکیل/ویرایش پرونده — patient record create & edit form (Figma "تشکیل پرونده"). */
 export default function PatientRecordFormPage() {
diff --git a/assets/admin/pages/PaymentDetailPage.tsx b/assets/admin/pages/PaymentDetailPage.tsx
index bc8ccc70..b6e77d38 100644
--- a/assets/admin/pages/PaymentDetailPage.tsx
+++ b/assets/admin/pages/PaymentDetailPage.tsx
@@ -114,7 +114,7 @@ export default function PaymentDetailPage() {
               {payment.refunds.map((r, i) => (
                 <InfoRow
                   key={i}
-                  label={formatDateTime(new Date(r.at * 1000).toISOString())}
+                  label={formatDateTime(r.at)}
                   value={
                     <span>
                       {formatRial(r.amount)}
diff --git a/docs/api/appointment-settings.md b/docs/api/appointment-settings.md
index 14be425f..fb602a2e 100644
--- a/docs/api/appointment-settings.md
+++ b/docs/api/appointment-settings.md
@@ -312,6 +312,7 @@ Get all date overrides for a doctor.
         "uuid": "...",
         "doctor_uuid": "...",
         "date": 1718476800,
+        "date_string": "2024-06-15",
         "active": false,
         "reason": "تعطیل خاص",
         "custom_slots": [],
@@ -322,7 +323,7 @@ Get all date overrides for a doctor.
 }
 ```
 
-> `date` is a Unix timestamp. `active: false` = entire day blocked. `active: true` with `custom_slots` = custom session schedule.
+> `date` is a Unix timestamp at **server-local midnight** (`Asia/Tehran`); `date_string` is the same day as `Y-m-d` and is what clients must render — converting the timestamp in a browser with `toISOString()` (UTC) shifts it one day back. `active: false` = entire day blocked. `active: true` with `custom_slots` = custom session schedule.
 
 ---
 
@@ -387,6 +388,7 @@ Create a date override.
       "uuid": "override-uuid-...",
       "doctor_uuid": "...",
       "date": 1718476800,
+      "date_string": "2024-06-15",
       "active": false,
       "reason": "تعطیل رسمی",
       "custom_slots": [],
@@ -490,6 +492,8 @@ Get all holidays for a doctor.
         "doctor_uuid": "...",
         "start_date": 1719792000,
         "end_date": 1720656000,
+        "start_date_string": "2024-07-01",
+        "end_date_string": "2024-07-11",
         "reason": "تعطیلات تابستانی",
         "active": true,
         "created_at": 1717000000
@@ -499,7 +503,7 @@ Get all holidays for a doctor.
 }
 ```
 
-> `start_date` and `end_date` are Unix timestamps. Holidays take **highest priority** — they block the day even if a date override exists.
+> `start_date` / `end_date` are Unix timestamps at **server-local midnight** (`Asia/Tehran`); `start_date_string` / `end_date_string` carry the same days as `Y-m-d` and are what clients must render (UTC conversion in the browser shifts them one day back). Holidays take **highest priority** — they block the day even if a date override exists.
 
 ---
 
@@ -536,6 +540,8 @@ Create a holiday range.
       "doctor_uuid": "...",
       "start_date": 1719792000,
       "end_date": 1720656000,
+      "start_date_string": "2024-07-01",
+      "end_date_string": "2024-07-11",
       "reason": "تعطیلات تابستانی",
       "active": true,
       "created_at": 1717000000
diff --git a/src/Appointment/Controller/AppointmentSettingsController.php b/src/Appointment/Controller/AppointmentSettingsController.php
index 4b4639da..8645fd54 100644
--- a/src/Appointment/Controller/AppointmentSettingsController.php
+++ b/src/Appointment/Controller/AppointmentSettingsController.php
@@ -42,6 +42,21 @@ class AppointmentSettingsController extends BaseController
         private readonly \App\Secretary\Security\SecretaryAccessChecker $secretaryAccess,
     ) {}
 
+    /**
+     * تاریخِ روزمحور (`Y-m-d`) را به نیمه‌شبِ همان روز در تایم‌زون سرور تبدیل می‌کند.
+     * بدون این نرمال‌سازی، ورودی‌هایی که ساعت دارند (مثلاً ISO با `Z`) روز را جابه‌جا
+     * می‌کنند. `null` یعنی ورودی نامعتبر.
+     */
+    private function parseDayTimestamp(string $value): ?int
+    {
+        $ts = strtotime(trim($value));
+        if ($ts === false) {
+            return null;
+        }
+
+        return (int) strtotime(date('Y-m-d', $ts) . ' 00:00:00');
+    }
+
     /**
      * نوع نوبت‌دهی پس از اولین ثبت غیرقابل‌تغییر است — اما فقط داخل همان context.
      * پزشکی که در مطب شخصی نوبت‌دهی اسلاتی دارد، همچنان می‌تواند در کلینیک سرویسی
@@ -289,8 +304,8 @@ class AppointmentSettingsController extends BaseController
             return $err;
         }
 
-        $timestamp = strtotime($dateStr);
-        if ($timestamp === false || $timestamp === -1) {
+        $timestamp = $this->parseDayTimestamp($dateStr);
+        if ($timestamp === null) {
             return $this->error(ErrorCodes::ERR_VALIDATION_001, 'فرمت تاریخ نادرست است', 422, 'date');
         }
 
@@ -320,8 +335,8 @@ class AppointmentSettingsController extends BaseController
         if (array_key_exists('reason', $data))       $override->setReason($data['reason']);
         if (array_key_exists('custom_slots', $data)) $override->setSetting($data['custom_slots']);
         if (!empty($data['date'])) {
-            $ts = strtotime($data['date']);
-            if ($ts !== false) $override->setDate($ts);
+            $ts = $this->parseDayTimestamp($data['date']);
+            if ($ts !== null) $override->setDate($ts);
         }
 
         $this->overrideRepo->save($override);
@@ -430,10 +445,10 @@ class AppointmentSettingsController extends BaseController
             return $this->error(ErrorCodes::ERR_ACCESS_DENIED, 'کلینیک فقط می‌تواند تعطیلی مخصوص خودش را ثبت کند', 403, 'clinic_uuid');
         }
 
-        $startTs = strtotime($startStr);
-        $endTs   = strtotime($endStr);
+        $startTs = $this->parseDayTimestamp($startStr);
+        $endTs   = $this->parseDayTimestamp($endStr);
 
-        if (!$startTs || !$endTs || $endTs < $startTs) {
+        if ($startTs === null || $endTs === null || $endTs < $startTs) {
             return $this->error(ErrorCodes::ERR_VALIDATION_001, 'تاریخ نادرست است', 422);
         }
 
@@ -461,12 +476,12 @@ class AppointmentSettingsController extends BaseController
         if (array_key_exists('active', $data))  $holiday->setActive((bool) $data['active']);
         if (array_key_exists('reason', $data))  $holiday->setReason($data['reason']);
         if (!empty($data['start_date'])) {
-            $ts = strtotime($data['start_date']);
-            if ($ts) $holiday->setStartDate($ts);
+            $ts = $this->parseDayTimestamp($data['start_date']);
+            if ($ts !== null) $holiday->setStartDate($ts);
         }
         if (!empty($data['end_date'])) {
-            $ts = strtotime($data['end_date']);
-            if ($ts) $holiday->setEndDate($ts);
+            $ts = $this->parseDayTimestamp($data['end_date']);
+            if ($ts !== null) $holiday->setEndDate($ts);
         }
 
         $this->holidayRepo->save($holiday);
diff --git a/src/Appointment/Entity/DateOverride.php b/src/Appointment/Entity/DateOverride.php
index 1b935f8d..39df5b6e 100644
--- a/src/Appointment/Entity/DateOverride.php
+++ b/src/Appointment/Entity/DateOverride.php
@@ -91,6 +91,9 @@ class DateOverride
             'clinic_uuid' => $this->clinic?->getUuid(),
             'context'     => $this->clinic === null ? 'personal' : 'clinic',
             'date'        => $this->date,
+            // نمایش تاریخ باید از این رشته خوانده شود؛ تبدیل timestamp در مرورگر
+            // با UTC انجام می‌شود و برای نیمه‌شبِ تهران یک روز عقب می‌افتد.
+            'date_string' => date('Y-m-d', $this->date),
             'active'      => $this->active,
             'reason'      => $this->reason,
             'custom_slots' => $this->setting ?? [],
diff --git a/src/Appointment/Entity/Holiday.php b/src/Appointment/Entity/Holiday.php
index 9db251b1..080272ea 100644
--- a/src/Appointment/Entity/Holiday.php
+++ b/src/Appointment/Entity/Holiday.php
@@ -90,6 +90,10 @@ class Holiday
             'scope'       => $this->clinic === null ? 'global' : 'clinic',
             'start_date'  => $this->startDate,
             'end_date'    => $this->endDate,
+            // نمایش تاریخ باید از این رشته‌ها خوانده شود؛ تبدیل timestamp در مرورگر
+            // با UTC انجام می‌شود و برای نیمه‌شبِ تهران یک روز عقب می‌افتد.
+            'start_date_string' => date('Y-m-d', $this->startDate),
+            'end_date_string'   => date('Y-m-d', $this->endDate),
             'active'      => $this->active,
             'reason'      => $this->reason,
             'created_at'  => $this->createdAt,
diff --git a/tests/Appointment/SpecialDateBoundaryTest.php b/tests/Appointment/SpecialDateBoundaryTest.php
new file mode 100644
index 00000000..6f4e9f50
--- /dev/null
+++ b/tests/Appointment/SpecialDateBoundaryTest.php
@@ -0,0 +1,112 @@
+<?php
+
+namespace App\Tests\Appointment;
+
+use App\Doctor\Entity\Doctor;
+use App\Tests\ApiTestCase;
+
+/**
+ * تاریخ خاص و تعطیلات باید دقیقاً همان روزِ ارسالی را نگه دارند: timestamp روی
+ * نیمه‌شبِ محلی و یک رشتهٔ `Y-m-d` کانونی در پاسخ، تا کلاینت مجبور به تبدیل
+ * timestamp (و جابه‌جایی یک‌روزه به‌خاطر UTC) نباشد.
+ */
+class SpecialDateBoundaryTest extends ApiTestCase
+{
+    private function makeDoctor(): Doctor
+    {
+        $owner  = $this->createUser(['ROLE_DOCTOR']);
+        $doctor = new Doctor($owner, 'دکتر تاریخ');
+        $this->em->persist($doctor);
+        $this->em->flush();
+
+        return $doctor;
+    }
+
+    public function testOverrideKeepsExactDayAndReturnsDateString(): void
+    {
+        $doctor = $this->makeDoctor();
+        $date   = date('Y-m-d', strtotime('+9 days'));
+
+        $body = $this->authJson('POST', '/api/v1/appointment-settings/date-override', $doctor->getUser(), [
+            'doctor_uuid' => $doctor->getUuid(),
+            'date'        => $date,
+            'active'      => false,
+        ]);
+
+        self::assertSame(201, $this->responseCode());
+        self::assertSame($date, $body['data']['data']['date_string']);
+        self::assertSame((int) strtotime($date . ' 00:00:00'), $body['data']['data']['date']);
+        self::assertSame($date, date('Y-m-d', $body['data']['data']['date']));
+    }
+
+    public function testOverrideNormalizesTimestampWithTimeToLocalMidnight(): void
+    {
+        $doctor = $this->makeDoctor();
+        $date   = date('Y-m-d', strtotime('+10 days'));
+
+        // ورودی ISO با ساعت (مثل چیزی که toISOString مرورگر می‌سازد) نباید روز را جابه‌جا کند.
+        $body = $this->authJson('POST', '/api/v1/appointment-settings/date-override', $doctor->getUser(), [
+            'doctor_uuid' => $doctor->getUuid(),
+            'date'        => $date . ' 23:45:00',
+            'active'      => false,
+        ]);
+
+        self::assertSame(201, $this->responseCode());
+        self::assertSame($date, $body['data']['data']['date_string']);
+        self::assertSame((int) strtotime($date . ' 00:00:00'), $body['data']['data']['date']);
+    }
+
+    public function testOverridePatchKeepsExactDay(): void
+    {
+        $doctor = $this->makeDoctor();
+        $first  = date('Y-m-d', strtotime('+11 days'));
+        $second = date('Y-m-d', strtotime('+12 days'));
+
+        $created = $this->authJson('POST', '/api/v1/appointment-settings/date-override', $doctor->getUser(), [
+            'doctor_uuid' => $doctor->getUuid(),
+            'date'        => $first,
+            'active'      => false,
+        ]);
+        $uuid = $created['data']['data']['uuid'];
+
+        $patched = $this->authJson('PATCH', "/api/v1/appointment-settings/date-override/{$uuid}", $doctor->getUser(), [
+            'date' => $second,
+        ]);
+
+        self::assertSame(200, $this->responseCode());
+        self::assertSame($second, $patched['data']['data']['date_string']);
+    }
+
+    public function testHolidayKeepsExactDaysAndReturnsDateStrings(): void
+    {
+        $doctor = $this->makeDoctor();
+        $start  = date('Y-m-d', strtotime('+13 days'));
+        $end    = date('Y-m-d', strtotime('+15 days'));
+
+        $body = $this->authJson('POST', '/api/v1/appointment-settings/holidays', $doctor->getUser(), [
+            'doctor_uuid' => $doctor->getUuid(),
+            'start_date'  => $start,
+            'end_date'    => $end,
+            'reason'      => 'سفر',
+        ]);
+
+        self::assertSame(201, $this->responseCode());
+        self::assertSame($start, $body['data']['data']['start_date_string']);
+        self::assertSame($end,   $body['data']['data']['end_date_string']);
+        self::assertSame((int) strtotime($start . ' 00:00:00'), $body['data']['data']['start_date']);
+        self::assertSame((int) strtotime($end . ' 00:00:00'),   $body['data']['data']['end_date']);
+    }
+
+    public function testInvalidDateIsRejected(): void
+    {
+        $doctor = $this->makeDoctor();
+
+        $this->authJson('POST', '/api/v1/appointment-settings/date-override', $doctor->getUser(), [
+            'doctor_uuid' => $doctor->getUuid(),
+            'date'        => 'not-a-date',
+            'active'      => false,
+        ]);
+
+        self::assertSame(422, $this->responseCode());
+    }
+}