SIM Cards and Mobile Internet in Vietnam: Which Operator Is Best for Foreigners in 2026

Buying a SIM card in Vietnam is easy. Buying one that is actually registered to your foreign passport, will not suddenly be blocked, and can still be serviced properly months later is less straightforward.

This became especially important in 2026, when Vietnam tightened subscriber identification rules. Mobile operators are required to verify customer information, and foreigners can be registered using a valid passport together with the required identity and biometric checks. So the fact that a SIM starts working immediately is no longer enough to assume everything is correct.

If you only need data for a week, a travel eSIM can solve the problem easily. But if you plan to keep the number for months, receive SMS, use it for Zalo, banking or other important services, the real priority is not the cheapest data package. It is whether the operator can properly register the number to a foreign passport and whether you can get support later if something goes wrong.

Which operator is best for foreigners?

It is important to separate how easy the operator is for a foreign customer to deal with from how easy the operator is for a foreign customer to deal with.

Independent Opensignal data gives Viettel a very large lead in Coverage Experience: 8.4 out of 10, compared with 5.3 for VinaPhone and 4.3 for MobiFone. Viettel also leads on network reliability and consistency.

That does not mean Viettel is always the fastest network. In nPerf testing covering April 2025 to March 2026, VinaPhone ranked first overall for mobile internet performance, including download, upload and latency. In major cities, the practical difference between the big three can be much smaller than the coverage difference in mountain or rural areas.

Foreigners are officially allowed to register SIM cards with a passport

Sometimes sellers or support staff give the impression that a SIM cannot be registered to a foreigner. That is not generally true.

Under current rules, a foreign national can register a mobile subscription using a valid passport, provided the document is valid for their lawful stay in Vietnam. Depending on the process, electronic identity and biometric verification can also be involved.

From 2026, verification became significantly stricter. Operators are expected to authenticate foreign subscriber information and biometric data, including checks linked to immigration records.

That is why old-style “tourist SIMs” that were pre-activated under someone else’s identity have become particularly risky.

The practical rule is simple:

A SIM should not merely work. It should be registered to you.

How to check whose name the number is registered under

After activation, do not leave the shop as soon as the 4G or 5G icon appears.

Check mobile data, incoming and outgoing SMS, make a call, and verify the registered subscriber details.

Vietnam uses the 1414 service for subscriber-information checks. For major operators, the common method is sending `TTTB` to 1414, after which you receive information about the registered owner.

VNSKY currently publishes a slightly different format: `TTTB_[document number]` sent to 1414.

If the returned details do not match your passport, or the operator cannot clearly confirm that the number belongs to you, I would not use that number for important accounts.

Viettel: the best coverage, but far from the best foreigner experience

If you are travelling throughout Vietnam, especially to Ha Giang, Cao Bang, northern mountain areas, rural regions or remote roads, Viettel remains the safest choice for coverage.

Independent network data supports this. Viettel has a major lead in geographical Coverage Experience and also ranks first for Reliability Experience and Consistent Quality.

Foreign customers can officially register with Viettel. Its standard prepaid connection procedures accept a foreign passport, and prepaid is generally the simplest choice for travellers.

Viettel also supports eSIM and competitive data plans. For example, current packages can provide very large monthly data allowances at relatively low prices, although eligibility can depend on the specific SIM and promotion.

Viettel’s biggest weakness is English support

This is where the foreigner experience is very different from the network quality itself.

Viettel’s main apps are heavily focused on Vietnamese users and are effectively Vietnamese-only for much of the experience.

This is not an old problem that has already disappeared. Foreign users were still complaining in 2026 that even the newer Viettel Tammi app lacked a proper English interface. Some long-term customers describe relying on screenshots and machine translation just to manage packages and account settings.

The older My Viettel services are being moved into Viettel Tammi, but there is no clear sign that the transition has solved the language problem.

So I would describe Viettel as:

the best network, but not the best customer experience for someone who does not speak Vietnamese.

For a long-term number, one major advantage is Viettel’s large network of physical branded stores. If something goes wrong, you can usually take your passport to a proper service point rather than relying only on chat support.

Changing phones can trigger biometric verification again

This is a newer 2026 issue that many foreign users discover only after something stops working.

From June 15, 2026, when a SIM is moved to another device, operators are required to detect the device change and may request renewed facial verification. Until that verification succeeds, outgoing calls and SMS can be restricted.

For a Vietnamese customer with local digital identification, this is already an extra step. For a foreigner whose operator app handles passports poorly or has no English interface, it may turn into a visit to a physical store.

This is not just theoretical. In June and July 2026, foreign Viettel customers discussed having to repeat passport verification. Some completed it in a shop in a few minutes, while others found that staff had difficulty processing foreign documents or that the first verification did not save correctly.

If the number matters to you, do not ignore verification messages after changing phones.

MobiFone: currently the easiest option for foreign tourists

MobiFone has something that Viettel badly lacks: an official process clearly designed for international visitors and available in English.

MobiFone operates an International Travel eSIM service where foreign customers can register with a passport. Travellers with an e-Visa can complete part of the process before arriving, while visa-exempt visitors can use official airport QR flows and complete passport eKYC after arrival.

As of the current 2026 offer, MobiFone can even issue one free Travel eSIM per valid passport every 30 days. After successful registration, it includes an initial 10 GB for the first 24 hours, after which tourist packages can be added.

Payment can be made with international Visa, Mastercard, JCB and American Express cards.

The official travel page is fully available in English, which makes a significant difference for a visitor who has just arrived in the country.

The My MobiFone app also officially supports English and Vietnamese. It can be used to check balances, activate packages, top up the account, convert SIM to eSIM and update prepaid customer information.

The English interface has historically not been translated perfectly, and some foreign users have complained about Vietnamese-only sections. Even so, MobiFone currently offers a much more coherent foreign-tourist experience than most competitors.

The trade-off

MobiFone’s geographical coverage is significantly weaker than Viettel’s.

In Opensignal’s Coverage Experience measure, MobiFone scored 4.3 compared with Viettel’s 8.4. However, where MobiFone coverage is available, performance is often very good. Its average Download Speed Experience is almost identical to Viettel’s, and it scored highly on availability.

For a typical route such as Ho Chi Minh City → Nha Trang → Da Nang → Hanoi, island holidays and normal life in major cities, MobiFone may actually be the best overall compromise for a foreign visitor.

For long mountain trips and remote areas, I would still choose Viettel.

VinaPhone: a very strong network, but only partly foreigner-friendly

VinaPhone often sits between the two more obvious choices, although technically the network is excellent.

In the 2026 nPerf study, VinaPhone ranked first in Vietnam for overall mobile internet performance.

Its packages are also competitive. For example, current 5G plans can provide several gigabytes per day at prices around 150,000 VND per month, although some packages are available only to eligible or newly activated numbers.

For foreigners, the interface is better than Viettel’s but still far from perfect.

My VNPT includes an English-language option. However, foreign users in 2026 still reported that parts of the app remained in Vietnamese, passport verification did not always work, video verification could fail, and getting English-language help was not always easy.

So if I were choosing VinaPhone for a number I intended to keep for months or years, I would register it at a proper VNPT/VinaPhone office with my passport rather than depend entirely on the app.

VNSKY: attractive tariffs, but this is where the real problem appeared

VNSKY is a good example of why a foreign customer should not choose a SIM purely based on data allowances.

It is a digital operator from DIGILIFE using MobiFone’s infrastructure. Its packages are genuinely attractive. For example, plans around 79,000 VND per month can include several gigabytes per day, while slightly more expensive packages add more data and calling benefits.

On paper, VNSKY supports foreign customers. Its current subscriber-registration documents include fields for passport details and visa information for foreigners, and the operator has published instructions on updating subscriber information under the newer verification rules.

But my real experience as a foreign user was different.

I used VNSKY because the package was good and inexpensive. The SIM worked normally at first, but eventually it became clear that the number had not been correctly registered to my foreign passport. After subscriber-data checks became stricter, the number was blocked.

The bigger problem started after the block.

With a major operator, I could normally visit a branded store with my passport and resolve the issue in person. With VNSKY in Nha Trang, there was no practical service office where I could simply walk in and fix the registration.

Support was essentially through Zalo and Facebook, responses were slow, and communication was in Vietnamese.

VNSKY officially has a hotline, online support channels and sales partners. But a sales network and the ability to solve a complicated passport-registration issue in person are not the same thing.

For a foreigner who needs a number long-term, that difference matters a lot.

After this experience, I would not use VNSKY or another small digital operator as my only important number unless I had already confirmed that the number was properly registered to my passport and I knew how support would work if the SIM were later restricted.

As a cheap secondary data SIM, it makes much more sense.

What about Vietnamobile?

Vietnamobile can also attract customers with low prices, but it has a much more fundamental weakness: coverage.

Independent Opensignal testing gave Vietnamobile a Coverage Experience score of only 1.4 out of 10, compared with 4.3 for MobiFone, 5.3 for VinaPhone and 8.4 for Viettel. Its average download experience was also far below the big three.

For that reason, I do not see much benefit in using Vietnamobile as the only SIM for travelling around the country.

As a cheap secondary SIM in one specific city, it may work perfectly well. But the savings are small compared with the reliability you give up.

Not every airport SIM is bad — registration is what matters

The blanket advice “never buy a SIM at the airport” is too simplistic.

MobiFone, for example, now has an official tourist eSIM process built around international arrivals, with passport verification.

The actual problem is unofficial sellers and pre-activated SIMs where nobody properly registers the number to your identity.

Recent travellers have described buying airport SIMs that worked immediately and then stopped working a day later because the number had not been properly registered. Other foreign customers discovered during later verification that their supposedly personal SIM was actually registered under someone else’s name and passport.

These are individual experiences, not proof that airport SIMs in general are unsafe. But they illustrate the risk very well.

The place of purchase matters less than whether the seller actually completes passport and biometric registration in your name.

How I would buy a SIM in Vietnam in 2026

If you need a normal Vietnamese mobile number, I would use the following process:

1. For Viettel or VinaPhone, go to an official branded service point with your original passport. For MobiFone, the official tourist eSIM process is also a strong option.
2. Ask directly whether the number will be registered to your passport, rather than receiving an already activated SIM.
3. After activation, verify the subscriber information through 1414 and test mobile data, SMS and an outgoing call before leaving.
4. Save the phone number, package name and purchase documents. If the number is important, also identify the nearest genuine service centre.
5. Do not immediately attach critical accounts to the number until you are satisfied that registration has been completed correctly.

If a seller never asks for your passport, does no identity verification and simply hands you an already working SIM, that should be a warning sign in 2026 rather than a sign of efficient service.

A local eSIM and a travel data eSIM are not the same thing

The word eSIM is used for two quite different products.

A local Viettel, MobiFone or VinaPhone eSIM is a normal Vietnamese SIM without a plastic card. It can have a local number, receive SMS and calls, and is subject to the same registration requirements as a physical SIM.

An international travel eSIM from an external provider often gives you data only. It may connect to Viettel, MobiFone or VinaPhone through roaming agreements, but you may not receive a Vietnamese phone number at all.

For a one-week trip where you mainly need Google Maps, messaging apps and Grab, a data-only eSIM can be enough.

If you need local calls, SMS, long-term Zalo use or other services linked to a Vietnamese number, a genuine local SIM is more useful.

MobiFone Travel eSIM is a notable middle ground because it is an official product of a Vietnamese operator, combines remote eSIM activation with local registration, and can include local calling.

Do tourists actually need a Vietnamese phone number?

For a short trip, not always.

Most common apps work entirely through data, and many bookings, rides and messages can be handled without local calls.

For longer stays, however, a local number becomes much more convenient. Delivery drivers, small local businesses, landlords and many local services still rely heavily on phone calls and SMS.

If you plan to use the number for banking, account recovery or other important verification, you should treat it as a long-term asset rather than a disposable tourist SIM.

In that situation, the existence of a real service office can be worth more than an extra 30 GB in a cheap monthly plan.

Which option would I personally choose?

The answer depends on the scenario.

MobiFone Travel eSIM I would first consider MobiFone Travel eSIM. The process is designed for foreigners, the website is in English, passport registration is supported, international cards work, and the packages are straightforward.

Viettel Viettel. The inconvenient interface is something I would tolerate in exchange for substantially better geographical coverage.

VinaPhone, MobiFone or Viettel VinaPhone, MobiFone or Viettel can all work well, but I would register the number properly and verify ownership immediately.

Very cheap secondary mobile data: VNSKY and similar digital offers can make sense, but after my own experience I would not rely on one as the only important foreign-owned number.

Mobile data should be a backup for remote work, not your only connection

If you live in Vietnam for months and work remotely, I would not replace proper home internet with a mobile SIM just because the package advertises 150 or 200 GB. Video calls, backups, large downloads and software updates can consume those allowances surprisingly quickly.

In a rented apartment, first test the actual Wi-Fi from the room where you plan to work. The main fixed-line providers include Viettel, VNPT and FPT, while many serviced apartments provide internet through the landlord or building.

For important remote work, the best setup is often home internet from one provider and a mobile SIM from another, so one network failure does not disconnect you completely.

For hotels and short-term rentals, mobile data is an excellent backup. But test it inside the actual room: concrete walls, floor level and the building’s position can affect indoor signal more than the difference between two attractive coverage maps.

The conclusion: registration and support matter more than the price per gigabyte

Mobile data in Vietnam is inexpensive across all major operators. The difference between 79,000, 150,000 and 250,000 VND per month is too small to choose an important long-term number purely by price.

Three things matter more: whether the number is correctly registered to your passport, whether the network works where you actually travel, and whether you can get help if the operator asks for new biometric verification six months later.

As of September 2026, my practical ranking is simple: Viettel for coverage; MobiFone for foreign-tourist convenience; VinaPhone as a strong city-focused compromise; VNSKY only with a clear understanding of the support limitations and after verifying ownership.

And after the 2026 changes, the most important rule is this:

If someone sells you a SIM and the internet starts working, that still does not prove the SIM is actually registered to you.

Checking immediately is much easier than trying to recover an important number after it has already been blocked.

Updated: September 2026.

Main sources: Decree 163/2024/NĐ-CP; Circular 08/2026/TT-BKHCN; Viettel Telecom; MobiFone; VNPT/VinaPhone; VNSKY/DIGILIFE; Opensignal Mobile Network Experience; nPerf Mobile Connections Barometer; recent foreign-user and traveller reviews on Google Play, the App Store and Reddit.