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

$3

No location permission and no READ_PHONE_STATE needed.

$3

TurboModule implementation with synchronous reads for simple integration.

$3

Works with Expo prebuild/dev-client workflows.

$3

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:

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

Installation

`bash
yarn add react-native-timezone
`

For iOS:

`bash
npx pod-install
`

Expo (development builds)

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

Usage

`tsx
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`. |