Vietnam has cheap, fast mobile data and a rapidly expanding 5G footprint. Local tourist SIMs are inexpensive and easy to buy on arrival, while travel eSIMs riding on Viettel and Vinaphone let you land already online.
Networks & coverage
Three operators run the physical networks: Viettel (by far the best and widest 4G/5G coverage), Vinaphone and MobiFone. Viettel launched 5G first, with Vinaphone following in late 2024; 4G is excellent nationwide while 5G is concentrated in Hanoi, Ho Chi Minh City and major cities. Travel eSIM brands such as Airalo, Holafly and Nomad resell this capacity.
eSIM or physical SIM?
If your phone supports eSIM, buy online and install before you fly. Physical tourist SIMs are sold at Noi Bai (Hanoi), Tan Son Nhat (Ho Chi Minh City) and Da Nang airports, plus operator stores; passport registration is required and airport prices are marked up. Check your handset is carrier-unlocked.
Data, calls & messaging
Travel eSIMs are typically data-only, while local Viettel/Vinaphone SIMs add call and SMS credit. Zalo is the dominant local messaging and calling app, with WhatsApp and Facebook Messenger also widely used, so a data-only plan suits most travellers.
How much data do you need?
As a rough guide: 3 GB for a few days, 5–15 GB for one-to-two weeks, or an unlimited plan for heavy navigation and tethering. Local data is so cheap that unlimited 30-day SIMs cost only a few dollars.