PrepaidHow to Use a Data-Only eSIM with WhatsApp, iMessage, and Telegram
- WhatsApp, iMessage, Telegram
- Dual SIM setup covered
- Data usage estimates
- Updated June 2026
Daniel Mercer
Lead eSIM Analyst
Previously at Analysys Mason covering APAC mobile markets (2016-2021)
How we testPublished June 2026 · Updated June 2026
The Basics
Why data-only eSIMs work with messaging apps.
WhatsApp, iMessage, Telegram, and Signal are internet-based messaging apps. They send messages and make calls over a data connection, not through the traditional phone network. Any source of internet works: WiFi, cellular data from a physical SIM, or cellular data from an eSIM.
A data-only travel eSIM provides cellular internet access on local networks abroad. It does not include a phone number, voice minutes, or SMS. Messaging apps do not need any of those. They need data, and the eSIM provides exactly that.
Your phone number remains on your home SIM card. WhatsApp, iMessage, and Telegram are registered to that number. The eSIM handles data routing. The home SIM handles identity. Both run simultaneously on any dual SIM phone.
Setting up WhatsApp with dual SIM and eSIM.
WhatsApp requires zero configuration when switching to eSIM data. The app uses whatever data connection your phone provides. Set your eSIM as the data line, and WhatsApp automatically routes through it.
- 1
Keep your home SIM installed
Your home SIM card stays in the phone. WhatsApp is registered to that number. Do not remove the home SIM even if you turn off its data roaming.
- 2
Set eSIM as your data line
On iPhone: Settings > Cellular > Cellular Data > select your travel eSIM. On Samsung: Settings > Connections > SIM Manager > Mobile Data > select your travel eSIM.
- 3
Open WhatsApp and use normally
Text messages, voice calls, and video calls all route through the eSIM data connection. Group chats, media sharing, and status updates work exactly as they do at home.
If you remove your home SIM entirely, WhatsApp still works as long as you have data. You will not receive SMS verification codes, but WhatsApp does not require re-verification unless you log out or switch devices.
Apple
Using iMessage and FaceTime over eSIM data.
iMessage sends messages over the internet between Apple devices. FaceTime makes voice and video calls over data. Both work over any data connection, including a travel eSIM.
iMessage is linked to your Apple ID, not your SIM card. When your eSIM provides the data connection, iMessage sends and receives through it automatically. Blue bubbles stay blue. Read receipts work. Tapback reactions work. No settings change is needed.
FaceTime audio and video calls also route through eSIM data. One important exception: FaceTime calls are blocked in the UAE and Saudi Arabia. In those countries, FaceTime will fail regardless of your data source.
If you send a message to a non-Apple device, it falls back to SMS. SMS uses your home SIM, not the eSIM. If your home SIM has no international SMS plan, that message may fail or incur charges. Consider using WhatsApp for cross-platform messaging abroad.
Other Apps
Telegram, Signal, and other messaging apps over eSIM.
Telegram uses data for all messages, calls, and media. It works identically over eSIM data as it does over WiFi or home cellular. Telegram accounts are tied to a phone number, but the app does not require that number's SIM to be actively providing data.
Signal operates the same way. All messages are encrypted end-to-end and route through data. Signal calls (voice and video) use the eSIM data connection. Signal is the most data-efficient calling app, using roughly 1 MB per minute for voice calls.
Other apps that work over eSIM data without configuration: Google Messages (RCS mode), Facebook Messenger, LINE, KakaoTalk, WeChat, Viber, and Zoom. Any app that uses an internet connection rather than the cellular voice network will work.
Traditional SMS and MMS use the cellular voice network, not data. They route through your home SIM, not the eSIM. If your home SIM has international roaming disabled, SMS will not send. Use data-based messaging apps instead.
Restrictions
Countries where VoIP calling is restricted.
Most countries allow VoIP calling without restriction. A small number of markets block or limit voice and video calls through messaging apps. Text messaging remains unaffected everywhere.
| Country | Status |
|---|---|
| UAE | Voice/video calls blocked. Text messaging works. |
| Saudi Arabia | Intermittent. Some calls connect, others fail. |
| China | WhatsApp/Telegram blocked entirely without VPN. |
| Qatar | Unrestricted. All VoIP apps work. |
| Oman | Partially restricted. Some apps blocked. |
In countries with VoIP restrictions, your data-only eSIM still provides full internet access for browsing, maps, email, and text messaging. Only voice and video calling features are affected.
Data Planning
How much data messaging apps use.
Messaging apps use very little data for text conversations. Voice and video calls consume more. Here is what each activity costs in data terms, based on real-world measurements.
| Activity | Per minute | Per hour |
|---|---|---|
| WhatsApp text messaging | ~0.01 MB | ~1 MB |
| WhatsApp voice call | ~1 MB | ~60 MB |
| WhatsApp video call | ~5 MB | ~300 MB |
| iMessage text | ~0.01 MB | ~1 MB |
| FaceTime audio | ~3 MB | ~180 MB |
| FaceTime video | ~8 MB | ~480 MB |
| Telegram text | ~0.01 MB | ~1 MB |
| Signal voice call | ~1 MB | ~60 MB |
A 1 GB eSIM plan supports roughly 16 hours of WhatsApp voice calling or 1,000+ hours of text messaging. For a 7-day trip, 1-2 GB covers normal messaging and occasional calls.
FAQ
eSIM and messaging apps: common questions.
Will I get a new WhatsApp number with an eSIM?
No. WhatsApp keeps the phone number you originally registered with. A data-only eSIM provides internet access but does not assign a new phone number. Your WhatsApp account, chats, and contacts remain unchanged.
Do I need to verify WhatsApp again after installing an eSIM?
No. WhatsApp verification is tied to your phone number, not your data connection. As long as you keep your home SIM active (even without data), WhatsApp stays verified. You only need to re-verify if you change your WhatsApp phone number.
Can I make WhatsApp calls over an eSIM data connection?
Yes, in most countries. WhatsApp voice and video calls work over any data connection. The exceptions are countries that block VoIP at the carrier level, including the UAE and Saudi Arabia. In those markets, WhatsApp text messaging still works.
How much data does a WhatsApp video call use?
A WhatsApp video call uses approximately 5 MB per minute on average. A 30-minute video call consumes about 150 MB. A 1 GB eSIM plan supports roughly 3 hours of video calling, plus normal messaging and browsing.
Does iMessage work with a data-only eSIM?
Yes. iMessage uses an internet connection to send and receive messages between Apple devices. A data-only eSIM provides that connection. Your iMessage account stays linked to your Apple ID and phone number. No reconfiguration is needed.
Stay connected abroad. Keep your number. Add data.
From $4.50/GB. Works with WhatsApp, iMessage, Telegram.