If you work online and you're heading to Vietnam in 2026, here's the short version before the detail: for your first few days, land with a Saily eSIM already switched on, and if you're staying more than three or four weeks — or heading into the mountains — add a Viettel physical SIM once you're settled. That split isn't a hedge. It's a direct consequence of two facts about Vietnam specifically: Viettel has the best rural coverage in the country by a wide margin, and none of the three local carriers sell an eSIM to tourists. So the convenient option and the best-coverage option are two different products, and the smart move is to use each where it wins.
Most guides bury that. Let's not.
The honest pick
Best local carrier: Viettel. It's the largest network in Vietnam, military-owned, and its 4G reaches places the other two simply don't — Ha Giang's loops, Sapa, the Mekong Delta, the Central Highlands. If reliable signal off the tourist trail matters to your work, Viettel is the answer and it isn't close.
Best eSIM for arrival: Saily. Clean app, plans from around $3.99, and it activates the moment you land instead of after a passport-registration queue. Airalo is the strong alternative and has one specific edge worth knowing about, covered below.
Who chooses which: Short trip (under ~3 weeks), or you just want to be online the second the plane doors open? eSIM, full stop. Long stay, rural work, or you need a Vietnamese phone number for Grab, food delivery, and local sign-ups? Viettel physical SIM. Many remote workers doing a month or more use both — eSIM for day one, Viettel for the rest.
What's actually available in Vietnam right now
| Option | Data / plan | Price (approx.) | Runs on | Where to get it | Passport needed? |
|---|---|---|---|---|---|
| Viettel (local SIM) | 7GB / 7 days; or ~2GB/day + calls, 30 days | 30,000₫ (~$1.20); 120,000₫ (~$5) | Viettel (best coverage) | Airport counters, Viettel stores | Yes |
| Vinaphone (local SIM) | 1GB/day, 50 min calls, 15 days | 199,000₫ (~$8) | Vinaphone | Airport, carrier shops | Yes |
| Mobifone (local SIM) | 1GB–250GB, 1–30 days | 90,000–250,000₫ (~$3–8) | Mobifone | Airport, carrier shops | Yes |
| Saily (eSIM) | ~5–20GB, or unlimited | From ~$3.99 | Local partner network | App / online, before you fly | No |
| Airalo (eSIM) | 1GB–20GB+ | ~$4.50 and up | Viettel | App / online, before you fly | No |
A few things in that table matter more than they look. Viettel's own data-only plans are astonishingly cheap — roughly a dollar for 7GB over a week is real, not a typo. Vinaphone's official tourist SIM is the priciest per gigabyte of the three but bundles international call minutes, which almost no remote worker needs in a WhatsApp world. And every physical SIM now requires your passport at the counter, because Vietnam tightened real-name SIM registration and cut off unregistered numbers. That's the change that makes eSIMs genuinely more convenient here than they were a couple of years ago.
Arrival: get online before you're standing in the terminal
The single most useful thing you can do is have connectivity live before you land, and in Vietnam that means an eSIM, because the local carriers don't offer one to visitors.
Install Saily at home on your normal Wi-Fi, buy a Vietnam plan, and set it to activate on arrival. When your plane touches down at Noi Bai (Hanoi), Tan Son Nhat (Ho Chi Minh City), or Da Nang, you're online walking to immigration — booking a Grab, messaging your host, dropping a "landed" into Slack — while everyone else is queuing at a SIM counter jet-lagged and mentally converting dong. A 5–10GB Saily plan is plenty for a week or two of maps, messaging, and light tethering, and if you want a genuine work buffer, its unlimited plan throttles only after a generous 5GB per day (down to 1 Mbps), which is more headroom than most rivals give you. Get a Saily eSIM here and set it up before your flight.
If you'd rather run on Viettel's network from the eSIM itself — worth it if you already know you're heading somewhere remote in the first few days — Airalo is the pick, because its Vietnam plans ride Viettel. You lose a little on app polish and fair-use generosity but gain the best physical coverage in the country without a passport queue. For most people arriving into a city, Saily is the smoother experience; for a rural-first itinerary, Airalo's Viettel routing is the reason to choose it.
The one thing to avoid on arrival: buying an overpriced airport SIM in a hurry. Counters at both major airports are legit and open late (Noi Bai's arrivals kiosks run roughly 6am–2am), but staff sometimes steer tired arrivals toward the most expensive plan. If you're going to buy a physical SIM at all, it's better done deliberately, not at the first counter you see.
The longer stay: why Viettel earns the passport hassle
For a month or more, the physical Viettel SIM becomes worth the fifteen minutes of registration. Three reasons:
- Coverage. This is the whole game. In Hanoi or Ho Chi Minh City any carrier is fine. The moment you leave — a homestay outside Hoi An, a co-working retreat in Da Lat, a motorbike week through the north — Viettel is the network that still has bars. Travellers repeatedly report Mobifone dropping out indoors and in the countryside where Viettel holds. If your income depends on a call not dropping, this is not the place to economize.
- Price. Viettel's local data plans are cheaper per gigabyte than any eSIM. Roughly $5 for a month of daily data is the kind of number that makes a 30-day eSIM look expensive by comparison.
- A local number. A Vietnamese number unlocks the everyday apps — Grab, food delivery, ride-hailing, occasional two-factor for local services. An eSIM gives you data but not a usable local voice line, and for a longer base that gap gets annoying.
Buy it from an actual Viettel store rather than a random phone stall — staff can register it properly on your passport, load the plan you actually want, and confirm data is running before you leave. Bring your passport; there's no way around the registration now.
5G, speed, and what your work actually needs
Vietnam switched on commercial 5G — Viettel and Vinaphone both launched it — but in 2026 it's still a big-city phenomenon, strongest in Hanoi and Ho Chi Minh City and thin everywhere else. Good news: you almost certainly don't need it. Vietnam's 4G is fast and dense enough for video calls, large uploads, and tethering a laptop for a full workday. Treat 5G as an occasional bonus in the cities, not a deciding factor. Reliable 4G that reaches where you're going beats headline 5G that only exists downtown — which, again, points at Viettel for coverage and any decent eSIM for convenience.
The verdict, plainly
- Weekend or short trip: One eSIM. Saily for a smooth city arrival; Airalo if you're going rural fast and want Viettel routing. Don't bother with a local SIM.
- A few weeks, city-based: Saily eSIM covers you comfortably. Add a Viettel SIM only if you want a local number.
- A month or more, or any serious rural time: Saily eSIM for day one, then a Viettel physical SIM for the stay. Best coverage, lowest running cost, and a local number for the apps that need one.
The reason this guide splits the recommendation instead of naming one winner is that Vietnam genuinely rewards it. The local carriers force a passport queue and sell no tourist eSIM, so the frictionless option is always going to be an eSIM you set up at home — and Saily is the one I'd hand a friend flying in. But Viettel's countryside coverage is a real advantage no eSIM fully replaces on a long, mobile stay. Use the eSIM to erase arrival-day friction; use Viettel to stay reliably online for the long haul.