In summary: a Vietnam eSIM gives you mobile data as soon as you land in Hanoi or Ho Chi Minh, without having to find a store or pay your Spanish operator's roaming fees (Vietnam is outside the EU). It relies on Viettel, Vinaphone, or Mobifone, covers cities and the coast well, and calculating between 1 and 2 GB per week for normal use will be more than enough.
Vietnam is one of Southeast Asia's star destinations, and arriving connected changes your trip: maps for Hanoi's motorbike chaos, a translator in Hoi An's markets, and data to book a night train or a Ha Long Bay excursion on the fly. A Vietnam eSIM gives you internet as soon as you land, without having to find a store or pay your operator's expensive roaming fees. Here's information on coverage, local operators, how many GB to bring, and how to activate it in a minute.
Does an eSIM work in Vietnam?
Yes. An eSIM works in Vietnam if your mobile is compatible: it connects to local networks like a physical SIM, but without a card or paperwork. You install it before leaving home, land in Hanoi or Ho Chi Minh, and have data in 1 minute, without going to any store or waiting in line at the airport.
It's the perfect option for backpackers and frequent travelers, because you don't have to rely on finding a shop to buy a SIM or having it registered with your passport, which is common in Vietnam with physical SIMs. Before buying, check if your phone supports eSIM: if you have doubts about what exactly this technology is, the guide on what a virtual eSIM is explains it without technical jargon. Almost all mid-range and high-end models from recent years are compatible.
In Vietnam, cheap physical SIMs are sold on every corner, especially in the tourist areas of Hanoi and Ho Chi Minh, but they involve bargaining, changing your usual card, and sometimes a document registration that becomes inconvenient if you're in a hurry. With an eSIM, you save all that: you arrive at Noi Bai (Hanoi) or Tan Son Nhat (Ho Chi Minh) airport already connected, order your Grab to the hotel, and start your trip seamlessly from the first minute.
Operators and coverage: Viettel and company
Travel eSIMs rely on existing Vietnamese operators; they don't create their own networks. The largest and with the best coverage is Viettel, followed by Vinaphone and Mobifone. Viettel reaches more rural and mountainous areas, so it's the one you'll want if you're venturing out of the cities into the interior.
4G coverage is very good in Hanoi, Ho Chi Minh, Da Nang, Hoi An, and throughout the coast. In Sapa, the northern mountains, and the more rural areas of the Mekong Delta, the signal drops but remains stable in tourist towns and along main roads. In Ha Long Bay, you'll have solid coverage from the coast and ports, although in the middle of a cruise among the karst islets, it might be intermittent due to the distance from antennas; this happens with any operator, not an eSIM fault.
| Operator | Main strength | Where it excels |
|---|---|---|
| Viettel | Best coverage in the country | Rural areas, Sapa, Mekong Delta |
| Vinaphone | Good speed in cities | Hanoi, Ho Chi Minh, Da Nang |
| Mobifone | Stable on the coast | Hoi An, Nha Trang, Da Nang |
An eSIM that connects to the best available network at each point gives you the maximum possible coverage without you having to choose the operator. If you want to understand why this works differently from your Spanish company's traditional roaming, take a look at the difference between eSIM and roaming.
How many GB do you need for Vietnam?
For a typical trip involving maps, messaging, social media, and photos, estimate between 1 and 2 GB per week. Vietnam is a destination where you'll heavily rely on translators (the alphabet and tones mean spoken English doesn't always work) and booking transport and accommodation on the fly, so if you're tight on data, aim for the higher end of the table.
| Duration | Light usage | Medium usage | Heavy usage |
|---|---|---|---|
| 1 week | 2 GB | 3 GB | 5 GB |
| 2 weeks | 3 GB | 5 GB | 10 GB |
| 1 month | 5 GB | 10 GB | 20 GB |
A tip: in Vietnam, hotel and cafe Wi-Fi is abundant and decent, so you can rely on it to upload photos and make video calls, and save your eSIM data for when you're out on the street, in a Grab, or at the market. If you also want to stretch every gigabyte to the maximum (for example, by disabling automatic updates or lowering streaming quality), the guide on how to save eSIM data when traveling has tricks that make a difference, especially on long trips where you won't be recharging every two days.
Hanoi, Ho Chi Minh, and the north-south route
The most common itinerary covers the country from north to south (or vice versa): Hanoi and Ha Long Bay in the north, Hoi An and Da Nang in the center, and Ho Chi Minh with the Mekong Delta in the south. With an eSIM, you maintain connectivity throughout the journey, even on night trains and long-distance buses that connect these stops.
Traveler's tip: In Vietnam, you'll use Grab a lot (the Asian equivalent of Uber, also for ordering food) to get around. It needs active data to function, so having stable internet on your mobile saves you from haggling with taxi drivers and unnecessary waits on the street.
On long train or bus journeys, having data saves you from boredom and keeps you located: you can follow the route on the map, notify your accommodation of your actual arrival time (delays are frequent), and download tickets or vouchers on the go. Mobile coverage follows the coastline quite well, so most of the trip you'll be connected without problems.
If your route continues outside of Vietnam, for example with a long layover in Europe on your return, you don't need to activate your Spanish line for roaming during those hours: you can have an eSIM for Europe just as easy to install.
Roaming in Vietnam: why your plan won't work
Vietnam is outside the European roaming zone, so your Spanish plan does not include free data there. As soon as you land, your operator will charge you for international roaming, and the cost will skyrocket compared to what you pay at home. If you want to understand exactly the difference between roaming and data roaming and why it pays operators to charge for it this way, the guide on what data roaming is breaks it down well.
The classic alternative before eSIM was to buy a local physical SIM or an international chip at the airport. It works, but it has its drawbacks: you swap out your usual SIM (and you can't receive verification SMS on your Spanish number while it's in), you wait in line, and sometimes you haggle over the price. If you're debating between the two options, the comparison of international chip vs. eSIM helps you decide based on your specific situation.
That said, be honest with yourself in your calculation: if you're only in Vietnam for a couple of days on a layover within a larger trip and you already have guaranteed Wi-Fi at the hotel and airport, you might not need to buy anything and Wi-Fi will suffice. An eSIM makes sense when you're going to be moving around, relying on Grab or Google Maps on the street, or if the trip lasts more than a couple of days.
How to activate your eSIM step by step
The convenient way is to install the eSIM with Wi-Fi at home and activate the data upon landing in Vietnam. This way, you arrive connected without depending on airport Wi-Fi, which in Noi Bai and Tan Son Nhat can be slow during peak hours.
- Buy the eSIM for Vietnam and receive the QR code instantly via email.
- With Wi-Fi, go to Settings > Mobile Data > Add eSIM and scan the QR.
- Label the eSIM ("Vietnam") so you don't confuse it with your Spanish line.
- Upon landing, activate the eSIM data and deactivate roaming for your usual line, so you aren't accidentally charged.
- Check the connection; if something goes wrong, review the step-by-step installation guide.
If this is your first eSIM and you want to overcome any hesitation before leaving, the step-by-step guide on how to install an eSIM will clarify it in minutes. A useful trick: if you've never used an eSIM, calmly test the installation process before your trip, for example with an eSIM for Spain on a random weekend, so that on the day of your flight to Hanoi you know exactly what to do. Our eSIM for Vietnam includes 24/7 Spanish support in case any questions arise during your trip.
Myths and what almost no one tells you
"With an eSIM, I don't need a Wi-Fi device or a backup plan." That's not entirely true. On a cruise through Ha Long, on some sections of a night train, or in remote areas of Sapa, the signal might disappear completely for minutes or hours. Download the offline map of the area on Google Maps before leaving the city; it's free and will save you if you lose coverage in the middle of an excursion.
"All eSIMs offer the same speed." Not exactly: it depends on which local operator your eSIM connects to in each area, and that varies. An eSIM that prioritizes Viettel will perform better outside major cities than one tied to a single, more urban operator.
"I can receive SMS from my Spanish bank while using the eSIM." If your mobile is dual SIM and you keep your physical line active in the background (no data, only for calls and SMS), then yes, you can continue receiving those codes. If, however, you insert a local Vietnamese physical SIM into your mobile's only physical tray, you lose that reception while it's in; with the eSIM on the second line, however, you don't have that problem.
"In Hanoi and Ho Chi Minh, traffic and noise don't affect the signal." Interestingly, they do have some influence: in Hanoi's Old Quarter, with narrow streets and buildings close to each other, the indoor signal in shops and ground-floor restaurants sometimes drops a notch compared to the street. Nothing serious, but if you need to make an important video call, step out onto the sidewalk.
"When it's not worth buying anything." If your layover in Vietnam is only a few hours at the airport and you're not going out, don't spend on an eSIM: the airport Wi-Fi, even if not perfect, will be enough for those hours.
Frequently asked questions
Which operator is best in Vietnam?
Viettel is the operator with the widest coverage in the country, especially in rural and mountainous areas like Sapa or the Mekong Delta. Vinaphone and Mobifone also work well in cities and on the coast. A travel eSIM connects to the best available network at each point, so you don't have to choose manually.
Is there free roaming in Vietnam with my Spanish plan?
No. Vietnam is outside the European roaming zone, so your Spanish plan does not include free data there. Your operator would charge you international roaming at standard rates, which is much more expensive than contracting a local eSIM before you leave. Always check the current price with your operator before traveling, just in case.
How many GB do I need for two weeks in Vietnam?
For two weeks of tourist travel, between 3 and 5 GB is usually enough if you take advantage of Wi-Fi in hotels and cafes, which is abundant in Vietnam. If you use Grab, a translator, and social media extensively without relying on Wi-Fi, budget around 10 GB to avoid any worries.
Does the eSIM work in Ha Long Bay?
Yes, from the coast and ports, with good 4G coverage. During the cruise through the islets, the signal might be intermittent due to the distance from the antennas. This is normal with any operator, not a problem specific to the eSIM; take advantage of those moments to disconnect between karst formations.
Can I use Grab and order food with the eSIM?
Yes. Grab, Google Maps, WhatsApp, and the rest of your apps work with eSIM data just like at home. In fact, having stable data is key in Vietnam for getting around with Grab and avoiding haggling over taxi prices on the street.
Do I need a different eSIM for Hanoi and for Ho Chi Minh?
No. The same eSIM for Vietnam works throughout the country, whether you're changing cities or areas, because it connects to the local network available wherever you are. There's no need to contract anything different between Hanoi, Ho Chi Minh, or the central part of the country.
Does the eSIM work as soon as I land, or do I have to do something first?
If you installed it with Wi-Fi before leaving home, you just need to activate the data for that line when you land (and deactivate roaming for your usual line). You don't need airport Wi-Fi or any additional management in Vietnam.
Conclusion
Vietnam is much more enjoyable when connected, and since it's outside the EU, roaming charges skyrocket as soon as you land. With an eSIM, you get data at a fixed price, coverage from Viettel and others, and activation in a minute, without registrations or bill surprises. Buy your eSIM for Vietnam before you fly and land in Hanoi or Ho Chi Minh already connected, ready to order your first Grab.
