Quick facts
| Networks | Viettel, VinaPhone (VNPT) and MobiFone |
| Identity | Passport, registered under Decree 163/2024/ND-CP |
| Phone | Unlocked, with 4G; VoLTE for normal calls |
| 2G | Switch-off scheduled for 15 September 2026 |
| 3G | Planned to close by 2028 |
| Alternative | An eSIM on the same networks, installed before you fly |
A disclosure first: VietSIM sells prepaid eSIMs for Vietnam, so we have a commercial interest in this topic. This page sets out the facts for both options so you can choose.
What a Vietnam SIM card gives you
A prepaid Vietnamese SIM card puts you on a local network. You pay local rates for data instead of roaming charges from your home carrier. Depending on the package, it can also give you a Vietnamese phone number for calls and SMS.
The three networks are Viettel, VinaPhone and MobiFone. They are compared side by side in Viettel, VinaPhone or MobiFone.
Registration: your passport is required
Vietnam does not allow anonymous mobile lines. Under Decree 163/2024/ND-CP, in force since 24 December 2024, the carrier records:
- your full name and date of birth,
- your passport number,
- digital copies of the document used and a time-stamped photo of the subscriber.
The carrier may only switch the line on after it has verified this information. As of September 2026, Circular 08/2026/TT-BKHCN, in force since 15 April 2026, adds that foreigners’ details are checked against the national immigration database.
Bring the passport you entered Vietnam with. The details on the SIM registration should match it exactly.
Check your phone before you buy
It must be unlocked. A phone locked to your home carrier rejects a foreign SIM card. Ask your carrier before you travel.
Count your SIM slots. In a phone with one physical slot, the Vietnamese card replaces your home SIM. Keep the home card somewhere safe.
Check VoLTE for calls. VoLTE means calls over 4G. Under the technical regulation QCVN 117:2023/BTTTT, 4G phones made or imported for the Vietnamese market must support VoLTE from 1 July 2024. The rule covers phones sold there, not the one in your pocket. Phones without it fall back to older networks for calls. The last 2G networks were scheduled to close on 15 September 2026, and the authorities plan to close 3G by 2028. Data is not affected, because it runs on 4G and 5G.
SIM card or eSIM
Both connect to the same networks. The difference is how you get the line and what happens to your home number.
| Physical SIM card | eSIM | |
|---|---|---|
| How you get it | In person, with your passport | Online, as a QR code |
| When it works | After you buy it in Vietnam | Installed before you fly, on when you land |
| Home SIM | Removed in single-slot phones | Stays in the phone |
| Phone needed | Unlocked, with a SIM slot | Unlocked and eSIM-capable |
Apple lists the iPhone XS, iPhone XS Max, iPhone XR and later models as eSIM-capable. On Android, search the settings for “eSIM” or see how to install an eSIM.
A physical card suits you if your phone has no eSIM support or you plan a long stay with a local package. An eSIM suits you if you want data the moment you land and prefer to keep your home SIM in place for bank codes. You can compare plans in the Vietnam eSIM store.
Your home number and WhatsApp
Changing SIM cards does not move your WhatsApp account. WhatsApp stays linked to the number you registered and works over any data connection. If WhatsApp ever asks you to verify again, it sends the code by SMS or phone call to that number. An eSIM keeps the home line in the phone, which makes this easier.
For ride-hailing, payments and other apps, see Apps to install for Vietnam. If you are unsure whether you need a separate router for a group, read Pocket Wi-Fi or eSIM.
If you choose an eSIM
VietSIM sells prepaid eSIMs on all three networks. Some VinaPhone plans include a Vietnamese number for incoming calls and SMS; each plan card says so. Install the eSIM over Wi-Fi before you fly, then follow Turn on your eSIM in Vietnam when you land. More questions are answered in the Vietnam phone and internet FAQ.