diff --git a/apps/web/app/components/Settings.tsx b/apps/web/app/components/Settings.tsx
index 0f8184d..7d4d114 100644
--- a/apps/web/app/components/Settings.tsx
+++ b/apps/web/app/components/Settings.tsx
@@ -1,5 +1,5 @@
 import { Card, CardBody, CardHeader } from '@nextui-org/react'
-import { type ReminderSetting, type User } from '@synk-cal/core'
+import { type ReminderSetting, ReminderTiming, type User } from '@synk-cal/core'
 import { UserInfo } from '~/components/UserInfo'
 
 import { Button, Input, Select, SelectItem } from '@nextui-org/react'
@@ -10,21 +10,31 @@ type Props = {
   user: User
   reminders: readonly ReminderSetting[]
   onChange: (reminders: ReminderSetting[]) => void
-  notifyBeforeOptions?: number[]
+  minutesBeforeOptions?: number[]
+  previousDayAtOptions?: { hour: number; minute: number }[]
   className?: string
 }
 
 const unitInJapanese = {
-  min: '分',
-  hour: '時間',
-  day: '日',
+  min: '分前',
+  hour: '時間前',
+  day: '日前',
 } as const
 
+const getTimingKey = (reminder: ReminderTiming) => {
+  if ('minutesBefore' in reminder) {
+    return String(reminder.minutesBefore)
+  } else {
+    return `${String(reminder.hour).padStart(2, '0')}:${String(reminder.minute).padStart(2, '0')}`
+  }
+}
+
 export function ReminderSettings({
   user,
   reminders,
   onChange,
-  notifyBeforeOptions = [5, 10, 15, 30, 60, 120, 180, 360, 720, 1440],
+  minutesBeforeOptions = [5, 10, 15, 30, 60, 120, 180, 360, 720, 1440],
+  previousDayAtOptions = Array.from({ length: 24 }).map((_, hour) => ({ hour, minute: 0 })),
   className,
 }: Props) {
   const addReminder = () => {
@@ -40,15 +50,38 @@ export function ReminderSettings({
     onChange(reminders.filter((reminder) => reminder.id !== id))
   }
 
-  const updateReminder = (id: string | number, minutesBefore: number) => {
+  const updateReminder = (id: string | number, value: ReminderTiming) => {
     onChange(
-      reminders.map((reminder) =>
-        reminder.id === id ? ({ ...reminder, minutesBefore } satisfies ReminderSetting) : reminder,
-      ),
+      reminders.map((reminder) => {
+        if (reminder.id === id) {
+          // @ts-expect-error
+          const { minutesBefore, hour, minute, ...rest } = reminder
+          return { ...rest, ...value }
+        }
+        return reminder
+      }),
     )
   }
 
   const locale = useLocale()
+  const options: { label: string; key: string; value: ReminderTiming }[] = [
+    ...minutesBeforeOptions.map((min) => {
+      const value = { minutesBefore: min }
+      let label = ''
+      if (min < 60) {
+        label = `${min} ${locale === 'ja' ? unitInJapanese.min : 'min'}`
+      } else if (min < 1440) {
+        label = `${min / 60} ${locale === 'ja' ? unitInJapanese.hour : 'hour'}`
+      } else {
+        label = `${min / 1440} ${locale === 'ja' ? unitInJapanese.day : 'day'}`
+      }
+      return { label, key: getTimingKey(value), value }
+    }),
+    ...previousDayAtOptions.map((value) => {
+      const key = getTimingKey(value)
+      return { label: locale === 'ja' ? `前日の ${key}` : `${key} the day before`, key, value }
+    }),
+  ]
 
   return (
     <div className={twMerge('flex flex-col gap-4', className)}>
@@ -76,23 +109,19 @@ export function ReminderSettings({
                 <Select
                   label={locale === 'ja' ? '通知タイミング' : 'Notify before'}
                   isRequired
-                  selectedKeys={[reminder.minutesBefore.toString()]}
+                  selectedKeys={[getTimingKey(reminder)]}
                   className="max-w-[200px]"
-                  onChange={(e) => updateReminder(reminder.id ?? i, Number(e.target.value))}
-                  items={notifyBeforeOptions.map((value) => {
-                    if (value < 60) {
-                      return { value, unit: 'min' as const, amount: value }
-                    } else if (value < 1440) {
-                      return { value, unit: 'hour' as const, amount: value / 60 }
-                    } else {
-                      return { value, unit: 'day' as const, amount: value / 1440 }
+                  onChange={(e) => {
+                    const value = options.find(({ key }) => key === e.target.value)?.value
+                    if (value) {
+                      updateReminder(reminder.id ?? i, value)
                     }
-                  })}
+                  }}
+                  items={options}
                 >
-                  {({ unit, amount, value }) => {
-                    const label = `${amount} ${locale === 'ja' ? unitInJapanese[unit] : unit}`
+                  {({ key, label }) => {
                     return (
-                      <SelectItem key={value.toString()} textValue={label}>
+                      <SelectItem key={key} textValue={label}>
                         {label}
                       </SelectItem>
                     )
diff --git a/apps/web/app/routes/settings.tsx b/apps/web/app/routes/settings.tsx
index 1c17d47..600307d 100644
--- a/apps/web/app/routes/settings.tsx
+++ b/apps/web/app/routes/settings.tsx
@@ -78,7 +78,7 @@ export default function SettingsRoute() {
         <ReminderSettings
           user={user}
           reminders={currentReminders}
-          notifyBeforeOptions={notifyBeforeOptions}
+          minutesBeforeOptions={notifyBeforeOptions}
           onChange={handleRemindersChange}
         />
       )}
diff --git a/apps/web/package.json b/apps/web/package.json
index 01ca5ac..efb70a3 100644
--- a/apps/web/package.json
+++ b/apps/web/package.json
@@ -7,11 +7,7 @@
   "bin": {
     "synk-cal": "./bin/server.js"
   },
-  "files": [
-    "bin",
-    "public",
-    "build"
-  ],
+  "files": ["bin", "public", "build"],
   "scripts": {
     "build": "remix vite:build",
     "dev": "remix vite:dev",
diff --git a/packages/core/src/config.test.ts b/packages/core/src/config.test.ts
index 4e4e91e..e4e9f80 100644
--- a/packages/core/src/config.test.ts
+++ b/packages/core/src/config.test.ts
@@ -4,17 +4,17 @@ import { parseConfig } from './config'
 
 describe('Config', () => {
   it('should parse valid configuration', () => {
-    const mockEnv = {
+    const mockEnv: NodeJS.ProcessEnv = {
+      NODE_ENV: 'test',
       GOOGLE_AUTH_SUBJECT: 'test@example.com',
       CALENDAR_IDS: 'calendar1,calendar2',
       REMINDER_SETTINGS: JSON.stringify([
         { minutesBefore: 10, notificationType: 'email' },
-        { minutesBefore: 30, notificationType: 'sms', target: '+1234567890' },
+        { hour: 9, minute: 0, notificationType: 'sms', target: '+1234567890' },
       ]),
       REMINDER_TEMPLATE: 'Your event {eventName} starts in {minutesBefore} minutes',
       WEBHOOK_URL: 'https://example.com/webhook',
       CALENDAR_PROVIDER: 'google',
-      REMINDER_MINUTES_BEFORE_OPTIONS: '1,2,3,4,5',
       REMINDER_SETTINGS_FIRESTORE_DATABASE_ID: 'test',
       REMINDER_SETTINGS_PROVIDER: 'firestore',
       AUTH_PROVIDER: 'google-iap',
@@ -25,23 +25,24 @@ describe('Config', () => {
     expect(parsedConfig).toEqual({
       GOOGLE_AUTH_SUBJECT: 'test@example.com',
       CALENDAR_IDS: ['calendar1', 'calendar2'],
+      TIMEZONE: 'UTC',
       REMINDER_SETTINGS: [
         { minutesBefore: 10, notificationType: 'email' },
-        { minutesBefore: 30, notificationType: 'sms', target: '+1234567890' },
+        { hour: 9, minute: 0, notificationType: 'sms', target: '+1234567890' },
       ],
       REMINDER_TEMPLATE: 'Your event {eventName} starts in {minutesBefore} minutes',
       WEBHOOK_URL: 'https://example.com/webhook',
       REMINDER_SETTINGS_PROVIDER: 'firestore',
       REMINDER_SETTINGS_FIRESTORE_DATABASE_ID: 'test',
-      REMINDER_MINUTES_BEFORE_OPTIONS: [1, 2, 3, 4, 5],
       CALENDAR_PROVIDER: 'google',
       AUTH_PROVIDER: 'google-iap',
     })
   })
 
   it('should handle missing optional values', () => {
-    const mockEnv = {
+    const mockEnv: NodeJS.ProcessEnv = {
       CALENDAR_IDS: 'calendar1',
+      NODE_ENV: 'test',
     }
 
     const parsedConfig = parseConfig(mockEnv)
@@ -49,20 +50,21 @@ describe('Config', () => {
     expect(parsedConfig).toEqual({
       GOOGLE_AUTH_SUBJECT: undefined,
       CALENDAR_IDS: ['calendar1'],
+      TIMEZONE: 'UTC',
       REMINDER_SETTINGS: [],
       REMINDER_TEMPLATE: undefined,
       WEBHOOK_URL: undefined,
       REMINDER_SETTINGS_PROVIDER: 'global',
       REMINDER_SETTINGS_FIRESTORE_DATABASE_ID: undefined,
-      REMINDER_MINUTES_BEFORE_OPTIONS: [5, 10, 15, 30, 60, 120, 180, 360, 720, 1440],
       AUTH_PROVIDER: undefined,
       CALENDAR_PROVIDER: 'google',
     })
   })
 
   it('should throw an error for invalid WEBHOOK_URL', () => {
-    const mockEnv = {
+    const mockEnv: NodeJS.ProcessEnv = {
       WEBHOOK_URL: 'invalid-url',
+      NODE_ENV: 'test',
     }
 
     expect(() => parseConfig(mockEnv)).toThrow(v.ValiError)
@@ -70,8 +72,12 @@ describe('Config', () => {
 
   it('should throw an error for invalid REMINDER_SETTINGS', () => {
     const mockEnv = {
-      REMINDER_SETTINGS: JSON.stringify([{ minutesBefore: 'invalid', notificationType: 'email' }]),
-    }
+      NODE_ENV: 'test',
+      REMINDER_SETTINGS: JSON.stringify([
+        { minutesBefore: 'invalid', notificationType: 'email' },
+        { hour: 25, minute: 0, notificationType: 'email' },
+      ]),
+    } as NodeJS.ProcessEnv
 
     expect(() => parseConfig(mockEnv)).toThrow(v.ValiError)
   })
@@ -79,7 +85,8 @@ describe('Config', () => {
   it('should throw an error for invalid REMINDER_SETTINGS JSON', () => {
     const mockEnv = {
       REMINDER_SETTINGS: 'invalid-json',
-    }
+      NODE_ENV: 'test',
+    } as NodeJS.ProcessEnv
 
     expect(() => parseConfig(mockEnv)).toThrow('Invalid REMINDER_SETTINGS JSON')
   })
diff --git a/packages/core/src/config.ts b/packages/core/src/config.ts
index db2ab81..0cc5329 100644
--- a/packages/core/src/config.ts
+++ b/packages/core/src/config.ts
@@ -1,10 +1,18 @@
 import * as v from 'valibot'
 
-const reminderSettingSchema = v.object({
-  minutesBefore: v.number(),
-  notificationType: v.string(),
-  target: v.optional(v.string()),
-})
+const reminderSettingSchema = v.union([
+  v.object({
+    notificationType: v.string(),
+    target: v.optional(v.string()),
+    minutesBefore: v.number(),
+  }),
+  v.object({
+    notificationType: v.string(),
+    target: v.optional(v.string()),
+    hour: v.pipe(v.number(), v.minValue(0), v.maxValue(23)),
+    minute: v.pipe(v.number(), v.minValue(0), v.maxValue(59)),
+  }),
+])
 
 export const ConfigSchema = v.object({
   GOOGLE_AUTH_SUBJECT: v.optional(v.string()),
@@ -13,6 +21,7 @@ export const ConfigSchema = v.object({
     v.optional(v.string()),
     v.transform((value) => value?.split(',') ?? []),
   ),
+  TIMEZONE: v.optional(v.string(), 'UTC'),
   REMINDER_SETTINGS: v.pipe(
     v.optional(v.string()),
     v.transform((value) => {
@@ -27,18 +36,6 @@ export const ConfigSchema = v.object({
     }),
     v.array(reminderSettingSchema),
   ),
-  REMINDER_MINUTES_BEFORE_OPTIONS: v.pipe(
-    v.optional(v.string(), '5,10,15,30,60,120,180,360,720,1440'),
-    v.transform((value) => {
-      return value.split(',').map((value) => {
-        const valueNumber = parseInt(value, 10)
-        if (isNaN(valueNumber)) {
-          throw new Error('Invalid REMINDER_MINUTES_BEFORE_OPTIONS')
-        }
-        return valueNumber
-      })
-    }),
-  ),
   REMINDER_TEMPLATE: v.optional(v.string()),
   REMINDER_SETTINGS_PROVIDER: v.optional(v.union([v.literal('global'), v.literal('firestore')]), 'global'),
   REMINDER_SETTINGS_FIRESTORE_DATABASE_ID: v.optional(v.string()),
@@ -53,7 +50,6 @@ export function parseConfig(env: NodeJS.ProcessEnv): Config {
     GOOGLE_AUTH_SUBJECT: env.GOOGLE_AUTH_SUBJECT,
     CALENDAR_PROVIDER: env.CALENDAR_PROVIDER,
     CALENDAR_IDS: env.CALENDAR_IDS,
-    REMINDER_MINUTES_BEFORE_OPTIONS: env.REMINDER_MINUTES_BEFORE_OPTIONS,
     REMINDER_SETTINGS: env.REMINDER_SETTINGS,
     REMINDER_SETTINGS_PROVIDER: env.REMINDER_SETTINGS_PROVIDER,
     REMINDER_SETTINGS_FIRESTORE_DATABASE_ID: env.REMINDER_SETTINGS_FIRESTORE_DATABASE_ID,
diff --git a/packages/core/src/reminder.ts b/packages/core/src/reminder.ts
index 5b760a0..1858fda 100644
--- a/packages/core/src/reminder.ts
+++ b/packages/core/src/reminder.ts
@@ -1,9 +1,17 @@
-export interface ReminderSetting {
+export type ReminderTiming =
+  | {
+      minutesBefore: number
+    }
+  | {
+      hour: number
+      minute: number
+    }
+
+export type ReminderSetting = {
   id?: string | number
-  minutesBefore: number
   notificationType: string
   target?: string
-}
+} & ReminderTiming
 
 export interface ReminderSettingsRepository {
   getReminderSettings: (userKey: string) => Promise<ReminderSetting[]>
diff --git a/packages/usecase/package.json b/packages/usecase/package.json
index 000acd0..f95a6a9 100644
--- a/packages/usecase/package.json
+++ b/packages/usecase/package.json
@@ -16,6 +16,7 @@
     "@synk-cal/core": "workspace:*",
     "@synk-cal/repository": "workspace:*",
     "date-fns": "^4.1.0",
+    "date-fns-tz": "^3.2.0",
     "eta": "^3.5.0"
   },
   "devDependencies": {
diff --git a/packages/usecase/src/process_reminders.test.ts b/packages/usecase/src/process_reminders.test.ts
index e0855f9..815b22f 100644
--- a/packages/usecase/src/process_reminders.test.ts
+++ b/packages/usecase/src/process_reminders.test.ts
@@ -5,14 +5,17 @@ import { processReminders } from './process_reminders'
 
 vi.mock('@synk-cal/core', () => ({
   config: {
-    REMINDER_TEMPLATE: 'Custom reminder: <%= it.title %> in <%= it.minutesBefore %> minutes.',
-    REMINDER_MINUTES_BEFORE_OPTIONS: [5, 10, 15, 30, 60, 120, 180, 360, 720, 1440],
+    REMINDER_TEMPLATE: 'Custom reminder: <%= it.title %> <%= it.minutesBefore ? `in ${it.minutesBefore} minutes` : `tomorrow at ${String(it.hour).padStart(2, "0")}:${String(it.minute).padStart(2, "0")}` %>.',
+    TIMEZONE: 'UTC',
   },
 }))
 
 vi.mock('eta', () => ({
   Eta: vi.fn().mockImplementation(() => ({
-    renderString: vi.fn((template, data) => `Custom reminder: ${data.title} in ${data.minutesBefore} minutes.`),
+    renderString: vi.fn((template, data) => 
+      `Custom reminder: ${data.title} ${
+        'minutesBefore' in data ? `in ${data.minutesBefore} minutes` : `tomorrow at ${String(data.hour).padStart(2, "0")}:${String(data.minute).padStart(2, "0")}`
+      }.`),
   })),
 }))
 
@@ -69,8 +72,12 @@ describe('processReminders', () => {
     ])
 
     const reminderSettingsMap: Record<string, ReminderSetting[]> = {
-      'user1@example.com': [{ minutesBefore: 10, notificationType: 'console' }],
-      'user2@example.com': [{ minutesBefore: 5, notificationType: 'webhook' }],
+      'user1@example.com': [
+        { minutesBefore: 10, notificationType: 'console' }
+      ],
+      'user2@example.com': [
+        { minutesBefore: 5, notificationType: 'webhook' }
+      ],
     }
 
     vi.mocked(mockReminderSettingsRepository.getReminderSettings).mockImplementation(async (userKey) => {
@@ -109,23 +116,23 @@ describe('processReminders', () => {
     expect(mockSendAllNotificationRepository.notify).not.toHaveBeenCalled()
   })
 
-  it('should not send notifications for invalid minutesBefore values', async () => {
-    const baseTime = parseISO('2023-06-01T10:00:00Z')
-    const eventStart = parseISO('2023-06-01T10:07:00Z')
+  it('should send notifications for day before at specific hour', async () => {
+    const baseTime = parseISO('2023-06-01T19:00:00Z') // UTC 19:00
+    const eventStart = parseISO('2023-06-02T10:00:00Z')
 
     vi.mocked(mockCalendarRepository.getEvents).mockResolvedValue([
       {
         id: '1',
         start: eventStart.toISOString(),
-        end: parseISO('2023-06-01T11:07:00Z').toISOString(),
+        end: parseISO('2023-06-02T11:00:00Z').toISOString(),
         title: 'Event 1',
         people: [{ email: 'user1@example.com', organizer: false }],
       },
     ])
 
     const reminderSettingsMap: Record<string, ReminderSetting[]> = {
-      'user1@example.com': [{ minutesBefore: 7, notificationType: 'console' }], // 7分は許可されていない値
-    }
+      'user1@example.com': [{ hour: 19, minute: 0, notificationType: 'console' }],
+    } 
 
     vi.mocked(mockReminderSettingsRepository.getReminderSettings).mockImplementation(async (userKey) => {
       return reminderSettingsMap[userKey] ?? []
@@ -140,18 +147,21 @@ describe('processReminders', () => {
       mockReminderSettingsRepository,
     )
 
-    expect(mockConsoleNotificationRepository.notify).not.toHaveBeenCalled()
+    expect(mockConsoleNotificationRepository.notify).toHaveBeenCalledWith(
+      'user1@example.com',
+      'Custom reminder: Event 1 tomorrow at 19:00.',
+    )
   })
 
   it('should handle multiple attendees for the same event', async () => {
-    const baseTime = parseISO('2023-06-01T10:00:00Z')
-    const eventStart = parseISO('2023-06-01T10:10:00Z')
+    const baseTime = parseISO('2023-06-01T19:00:00Z')
+    const eventStart = parseISO('2023-06-02T10:10:00Z')
 
     vi.mocked(mockCalendarRepository.getEvents).mockResolvedValue([
       {
         id: '1',
         start: eventStart.toISOString(),
-        end: parseISO('2023-06-01T11:10:00Z').toISOString(),
+        end: parseISO('2023-06-02T11:10:00Z').toISOString(),
         title: 'Event 1',
         people: [
           { email: 'user1@example.com', organizer: false },
@@ -161,8 +171,8 @@ describe('processReminders', () => {
     ])
 
     const reminderSettingsMap: Record<string, ReminderSetting[]> = {
-      'user1@example.com': [{ minutesBefore: 10, notificationType: 'console' }],
-      'user2@example.com': [{ minutesBefore: 10, notificationType: 'webhook' }],
+      'user1@example.com': [{ hour: 19, minute: 0, notificationType: 'console' }],
+      'user2@example.com': [{ hour: 19, minute: 0, notificationType: 'webhook' }],
     }
 
     vi.mocked(mockReminderSettingsRepository.getReminderSettings).mockImplementation(async (userKey) => {
@@ -181,33 +191,41 @@ describe('processReminders', () => {
 
     expect(mockConsoleNotificationRepository.notify).toHaveBeenCalledWith(
       'user1@example.com',
-      'Custom reminder: Event 1 in 10 minutes.',
+      'Custom reminder: Event 1 tomorrow at 19:00.',
     )
 
     expect(mockWebhookNotificationRepository.notify).toHaveBeenCalledWith(
       'user2@example.com',
-      'Custom reminder: Event 1 in 10 minutes.',
+      'Custom reminder: Event 1 tomorrow at 19:00.',
     )
   })
 
   it('should handle multiple reminder settings for the same user', async () => {
-    const baseTime = parseISO('2023-06-01T10:00:00Z')
-    const eventStart = parseISO('2023-06-01T10:10:00Z')
+    const baseTime = parseISO('2023-06-01T19:00:00Z')
+    const event1Start = parseISO('2023-06-01T19:10:00Z') // For minutesBefore
+    const event2Start = parseISO('2023-06-02T10:10:00Z') // For hour/minute
 
     vi.mocked(mockCalendarRepository.getEvents).mockResolvedValue([
       {
         id: '1',
-        start: eventStart.toISOString(),
-        end: parseISO('2023-06-01T11:10:00Z').toISOString(),
+        start: event1Start.toISOString(),
+        end: parseISO('2023-06-01T20:10:00Z').toISOString(),
         title: 'Event 1',
         people: [{ email: 'user1@example.com', organizer: false }],
       },
+      {
+        id: '2',
+        start: event2Start.toISOString(),
+        end: parseISO('2023-06-02T11:10:00Z').toISOString(),
+        title: 'Event 2',
+        people: [{ email: 'user1@example.com', organizer: false }],
+      },
     ])
 
     const reminderSettingsMap: Record<string, ReminderSetting[]> = {
       'user1@example.com': [
         { minutesBefore: 10, notificationType: 'console' },
-        { minutesBefore: 10, notificationType: 'webhook' },
+        { hour: 19, minute: 0, notificationType: 'webhook' },
       ],
     }
 
@@ -232,7 +250,7 @@ describe('processReminders', () => {
 
     expect(mockWebhookNotificationRepository.notify).toHaveBeenCalledWith(
       'user1@example.com',
-      'Custom reminder: Event 1 in 10 minutes.',
+      'Custom reminder: Event 2 tomorrow at 19:00.',
     )
   })
 
diff --git a/packages/usecase/src/process_reminders.ts b/packages/usecase/src/process_reminders.ts
index ca449dd..3aebd67 100644
--- a/packages/usecase/src/process_reminders.ts
+++ b/packages/usecase/src/process_reminders.ts
@@ -1,9 +1,34 @@
-import type { CalendarRepository, NotificationRepository, ReminderSettingsRepository } from '@synk-cal/core'
+import type {
+  CalendarRepository,
+  NotificationRepository,
+  ReminderSetting,
+  ReminderSettingsRepository,
+} from '@synk-cal/core'
 import { config } from '@synk-cal/core'
-import { addMinutes, isSameMinute, parseISO, subMinutes } from 'date-fns'
+import { addDays, isSameMinute, parseISO, subMinutes } from 'date-fns'
+import { formatInTimeZone, fromZonedTime } from 'date-fns-tz'
 import { Eta } from 'eta'
 
-const DEFAULT_TEMPLATE = 'Reminder: "<%= it.title %>" starts in <%= it.minutesBefore %> minutes.'
+const DEFAULT_TEMPLATE = `Reminder: "<%= it.title %>" starts <%= 
+  it.minutesBefore !== undefined 
+    ? \`in \${it.minutesBefore} minutes\` 
+    : \`tomorrow at \${String(it.hour).padStart(2, '0')}:\${String(it.minute).padStart(2, '0')}\` 
+%>.`
+
+const getReminderTime = (eventStart: Date, setting: ReminderSetting) => {
+  const timezone = config.TIMEZONE
+
+  if ('minutesBefore' in setting) {
+    return subMinutes(eventStart, setting.minutesBefore)
+  } else {
+    // Get the date of the day before the event
+    const reminderDateStr = formatInTimeZone(addDays(eventStart, -1), timezone, 'yyyy-MM-dd')
+    // Set the specified time
+    const reminderTimeStr = `${reminderDateStr}T${String(setting.hour).padStart(2, '0')}:${String(setting.minute).padStart(2, '0')}:00`
+    // Convert to UTC considering timezone
+    return fromZonedTime(reminderTimeStr, timezone)
+  }
+}
 
 export async function processReminders(
   baseTime: Date,
@@ -14,18 +39,15 @@ export async function processReminders(
   const eta = new Eta()
 
   // Get all events first
-  const maxMinutesBefore = Math.max(...config.REMINDER_MINUTES_BEFORE_OPTIONS)
   const events = (
     await Promise.all(
-      calendarRepositories.map((calendarRepository) =>
-        calendarRepository.getEvents(baseTime, addMinutes(baseTime, maxMinutesBefore)),
-      ),
+      calendarRepositories.map((calendarRepository) => calendarRepository.getEvents(baseTime, addDays(baseTime, 1))),
     )
   ).flat()
   console.debug('Fetched events', events.map((e) => `${e.title} (${e.start})`).join('\n'))
 
   const notifications: Array<{ repository: NotificationRepository; target: string; message: string }> = []
-  const reminderSettingsCache = new Map<string, Array<{ minutesBefore: number; notificationType: string }>>()
+  const reminderSettingsCache = new Map<string, ReminderSetting[]>()
 
   // Process each event
   for (const event of events) {
@@ -54,22 +76,17 @@ export async function processReminders(
 
       // Check each reminder setting for the attendee
       for (const setting of reminderSettings) {
-        // Skip if minutesBefore is not in the allowed options
-        if (!config.REMINDER_MINUTES_BEFORE_OPTIONS.includes(setting.minutesBefore)) {
-          console.debug(`Invalid minutesBefore value: ${setting.minutesBefore} for ${attendee.email}`)
-          continue
-        }
-
         const notificationRepository = notificationRepositories[setting.notificationType]
         if (!notificationRepository) {
           console.error(`No notification repository found for type: ${setting.notificationType}`)
           continue
         }
 
-        const reminderTime = subMinutes(parseISO(event.start), setting.minutesBefore)
-        if (!isSameMinute(reminderTime, baseTime)) {
+        const reminderTime = getReminderTime(parseISO(event.start), setting)
+        const isTimeMatch = isSameMinute(reminderTime, baseTime)
+        if (!isTimeMatch) {
           console.debug(
-            `Event "${event.title}" is not within ${setting.minutesBefore} minutes of ${baseTime} for ${attendee.email}`,
+            `Event "${event.title}" reminder time ${reminderTime} does not match current time ${baseTime} for ${attendee.email}`,
           )
           continue
         }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 637d813..6c9ce8c 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -302,6 +302,9 @@ importers:
       date-fns:
         specifier: ^4.1.0
         version: 4.1.0
+      date-fns-tz:
+        specifier: ^3.2.0
+        version: 3.2.0(date-fns@4.1.0)
       eta:
         specifier: ^3.5.0
         version: 3.5.0
@@ -3895,6 +3898,11 @@ packages:
     resolution: {integrity: sha512-BS8PfmtDGnrgYdOonGZQdLZslWIeCGFP9tpan0hi1Co2Zr2NKADsvGYA8XxuG/4UWgJ6Cjtv+YJnB6MM69QGlQ==}
     engines: {node: '>= 0.4'}
 
+  date-fns-tz@3.2.0:
+    resolution: {integrity: sha512-sg8HqoTEulcbbbVXeg84u5UnlsQa8GS5QXMqjjYIhS4abEVVKIUwe0/l/UhrZdKaL/W5eWZNlbTeEIiOXTcsBQ==}
+    peerDependencies:
+      date-fns: ^3.0.0 || ^4.0.0
+
   date-fns@4.1.0:
     resolution: {integrity: sha512-Ukq0owbQXxa/U3EGtsdVBkR1w7KOQ5gIBqdH2hkvknzZPYvBxb/aa6E8L7tmjFtkwZBu3UXBbjIgPo/Ez4xaNg==}
 
@@ -12130,6 +12138,10 @@ snapshots:
       es-errors: 1.3.0
       is-data-view: 1.0.2
 
+  date-fns-tz@3.2.0(date-fns@4.1.0):
+    dependencies:
+      date-fns: 4.1.0
+
   date-fns@4.1.0: {}
 
   debug@2.6.9: