React Native Timezone

Fast, privacy-first timezone and country detection for React Native with zero extra permissions.

react-native-timezone gives you:

• Current timezone ID
• Best current country from telephony (network-first, then SIM fallback)
• Locale country fallback
• Android auto-timezone setting status

Why this package

Privacy-first

No location permission and no READ_PHONE_STATE needed.

Native + fast

TurboModule implementation with synchronous reads for simple integration.

Expo development builds ready

Works with Expo prebuild/dev-client workflows.

Lightweight

Measured from the v3.2.1 package (February 7, 2026):

• Publish tarball: ~13.2 KB (varies slightly between pack runs)
• Installed package contents (unpacked): 52,165 bytes (~51.0 KB)
• JS runtime payload (CommonJS entry used by Metro): 1,288 bytes raw, 706 bytes gzip

Compatibility

| React Native | New Architecture | Status | | --- | --- | --- | | >= 0.71.0 | Supported | Compatible | | 0.76.x | Default New Arch | Verified in this repo | | 0.81.x | Default New Arch | Verified in example app |

iOS note on telephony APIs

Apple has deprecated CTCarrier APIs with no direct replacement. This can make telephony country unavailable on newer iOS versions, depending on device/network/privacy behavior.

Recommended pattern:

const bestCountry =
  Timezone.getRegionByTelephony() ?? Timezone.getRegionByLocale();

Installation

yarn add react-native-timezone

For iOS:

npx pod-install

Expo (development builds)

npx expo install react-native-timezone
npx expo prebuild
npx expo run:ios

Usage

import { useEffect } from 'react';
import Timezone from 'react-native-timezone';

export default function App() {
  useEffect(() => {
    const timezone = Timezone.getTimeZone();
    const isAutoTimeZoneEnabled = Timezone.isAutoTimeZoneEnabled();
    const telephonyRegion = Timezone.getRegionByTelephony();
    const localeRegion = Timezone.getRegionByLocale();
    const bestCountry = telephonyRegion ?? localeRegion;

    console.log({
      timezone,
      isAutoTimeZoneEnabled,
      telephonyRegion,
      localeRegion,
      bestCountry,
    });
  }, []);

  return null;
}

See the example app.

API

| API | Description | | --- | --- | | getTimeZone() | Returns current timezone ID (for example Asia/Colombo, Europe/Berlin). | | isAutoTimeZoneEnabled() | Android only. Returns true or false; returns null on iOS. | | getRegionByTelephony() | Returns best current telephony country (network-first, then SIM fallback) as uppercase ISO code (for example LK, US) or null. | | getRegionByLocale() | Returns locale country as uppercase ISO code (for example LK, US) or null. |