International Roaming vs. Local SIM: Which is Cheaper in Vietnam?

You land in Vietnam, the phone buzzes with a “Welcome” text from your home carrier, and you need a Grab ride, a map and a way to message your hotel. Do you let roaming handle it, or do you spend ten minutes buying a local SIM? In 2026 the price gap between the two is bigger than ever, and the wrong choice can cost you more than a night in a decent hotel. This guide uses an exchange rate of about 1 USD = 25,000 VND throughout, so you can compare the numbers directly.

What International Roaming Really Costs in Vietnam

International roaming lets you use your own number and plan in Vietnam through agreements between your home carrier and local Vietnamese networks. It works the moment you land, and that convenience is the only real selling point.

The danger is what happens without a plan. Standard per-use rates are extreme:

• Data: upwards of 250,000 VND (10 USD) per MB
• Calls: 50,000–100,000 VND (2–4 USD) per minute
• SMS: 5,000–10,000 VND (0.2–0.4 USD) per message

At those rates, one map refresh or a few photos in a group chat can wipe out a day’s budget. This is the classic bill shock: people underestimate how much data a phone uses in the background, and the invoice arrives after they get home.

Roaming passes soften the blow, but not by much. Daily passes usually cost 250,000–500,000 VND (10–20 USD) per day for a limited high-speed allowance, often 500MB to 2GB, then throttled speeds, plus a few calls and texts. Monthly passes run 1,000,000–2,500,000 VND (40–100 USD) for roughly 5GB to 20GB, and many are built for specific regions rather than global travel. Roaming data can also be deprioritised compared with local users, so speeds may drop when networks are busy.

Roaming has one honest advantage besides convenience: you keep your home number. That helps with two-factor authentication codes and with contacts who only have that number. For a one- or two-day stopover, or as an emergency backup, it makes sense. For anything longer, it does not.

What a Local SIM Costs: Viettel, Mobifone and Vinaphone

Three operators run Vietnam’s mobile market: Viettel, Mobifone and Vinaphone (a VNPT brand). All offer 4G nationwide and growing 5G in major cities and tourist areas. Tourist packages typically last 7, 15 or 30 days and bundle high-speed data, local call minutes and local SMS. Package names, allowances and prices change often, so treat the figures below as typical 2026 offers and confirm at the counter.

Viettel (viettel.vn)

Viettel is the largest operator, with the widest coverage, especially in rural and remote areas. It is generally seen as the most reliable network, which matters if you plan to ride the Ha Giang loop or visit the Central Highlands.

• Tourist Data Pack 15D: 5GB per day (75GB total), then throttled to 256kbps, plus 50 local minutes and 20 local SMS. About 200,000 VND (8 USD).
• Tourist Unlimited 30D: unlimited high-speed data under a fair usage policy (for example 3GB per day, then throttled), 100 local minutes and 50 local SMS. About 350,000 VND (14 USD).

Mobifone (mobifone.vn)

Mobifone is the second-largest operator, with strong urban coverage and competitive prices.

• Welcome Vietnam SIM 7D: 3GB per day (21GB total), then throttled, plus 30 local minutes. About 100,000 VND (4 USD).
• Mobifone Tourist 30D: 2GB per day (60GB total), 100 local minutes, 10 international minutes and 50 local SMS. About 300,000 VND (12 USD).

Vinaphone (vinaphone.vn)

Vinaphone is third-largest, with good coverage in cities and tourist spots and often attractive data deals.

• VNPT Tourist SIM 15D: 4GB per day (60GB total), then throttled, plus 60 local minutes. About 180,000 VND (7.2 USD).
• Vinaphone Travel Unlimited: unlimited high-speed data under a fair usage policy (for example 2.5GB per day), 80 local minutes, valid 30 days. About 320,000 VND (12.8 USD).

eSIM Options: Keep Your Home Number and Pay Local Prices

If your phone supports eSIM, you do not need a physical card at all. Viettel, Mobifone and Vinaphone all offer tourist eSIMs, activated by scanning a QR code. Generally they cost the same as the physical SIM packages. You can buy them at airports or official stores.

Compatible phones include iPhone XS/XR and newer, Google Pixel 3 and newer, and Samsung Galaxy S20 and newer. To install, go to Settings, then Cellular/Mobile Data, then Add eSIM or Add Data Plan, and scan the code.

The biggest benefit is that your home SIM stays active in the other slot. You can still receive calls, SMS and verification codes on your home number, while the Vietnamese eSIM handles data. Set your data line to the Vietnamese eSIM and switch off data roaming on the home line so nothing leaks through at roaming rates.

Global eSIM providers such as Airalo and Holafly are the middle option. They deliver international data packages via eSIM before you even fly, so you land already connected. They often cost less than traditional roaming but are still typically more expensive than a local Vietnamese SIM. They also give you data only, with no local Vietnamese number. That can be a problem for some local services that send codes by SMS. They suit travelers who value arriving connected over saving every dong.

Step-by-Step: Buying and Activating a SIM on Arrival

The Viettel, Mobifone and Vinaphone kiosks at Noi Bai, Tan Son Nhat and Da Nang airports are usually easy to spot. Airport prices can be slightly higher for convenience, but activation takes about 5–10 minutes.

1. Find a seller. Use an airport kiosk, or an official store in any city. Look for “Cửa hàng Viettel,” “Cửa hàng Mobifone,” or “Cửa hàng VNPT”/”Vinaphone.”
2. Choose a plan. Match the data, calls and duration to your trip. Most visitors need data far more than minutes.
3. Hand over your passport. Registration is a strict government requirement. Staff will scan or copy it and may take a quick photo of you.
4. Pay. You pay the stated fee for the SIM and package.
5. Let staff activate it. They insert the SIM, activate it and check it works. Expect 5–15 minutes depending on the queue. For an eSIM, they give you a QR code to scan.
6. Test before you leave the counter. Check data, calls and SMS.

Official stores are the safest alternative to the airport. You can also buy pre-registered Viettel SIMs from online retailers or travel agencies for airport pickup or hotel delivery, but check that the seller is legitimate. Smaller convenience shops may sell Mobifone SIMs. Make sure they register the SIM with your passport.

Topping Up Credit

If your package runs out or you need extra call credit, topping up in Vietnam is simple.

Scratch cards

Phone shops and convenience stores sell cards for all three networks in denominations from 20,000 VND to 500,000 VND.

1. Buy a card for your provider.
2. Scratch the silver panel to reveal a 12–14 digit code.
3. Dial *100*<scratch_card_code># and press call. This is the same format for Viettel, Mobifone and Vinaphone.
4. Wait for the SMS confirming the top-up.

Apps and wallets

• My Viettel, My MobiFone and My VNPT (App Store and Google Play) let you top up, check your balance and manage packages.
• MoMo and ZaloPay, two of Vietnam’s popular e-wallets, can also top up phone credit.
• If you open a local bank account, its mobile app often has a top-up function too.

2026 Budget Reality

Here is how the real costs stack up for a 30-day stay, using the typical packages above. Roaming figures use the daily pass range of 250,000–500,000 VND (10–20 USD).

• Budget: Mobifone Welcome Vietnam SIM 7D at about 100,000 VND (4 USD) for a one-week trip. A Vinaphone 15D SIM at about 180,000 VND (7.2 USD) covers two weeks.
• Mid-range: Mobifone Tourist 30D at about 300,000 VND (12 USD) or Vinaphone Travel Unlimited at about 320,000 VND (12.8 USD) for a full month.
• Comfortable: Viettel Tourist Unlimited 30D at about 350,000 VND (14 USD), with the widest coverage. Add a pocket Wi-Fi rental at 75,000–150,000 VND (3–6 USD) per day if you travel as a group.

Now the roaming comparison. A ten-day trip on daily passes would cost 2,500,000–5,000,000 VND (100–200 USD). The same ten days on a local SIM costs 100,000–350,000 VND (4–14 USD). Even a roaming monthly pass at 1,000,000–2,500,000 VND (40–100 USD) buys far less data than a local tourist SIM at 300,000–350,000 VND (12–14 USD).

Side by side:

• Data allowance: roaming is limited and quickly throttled. Local SIMs give 2–5GB per day or unlimited under fair use.
• Calls and SMS: roaming is expensive per use or capped by plan. Local SIMs include local minutes and texts, sometimes international minutes.
• Speed: roaming can be deprioritised. A local SIM gets full access to local 4G/5G.
• Convenience: roaming keeps your home number with no setup. A local SIM means a new number and a quick setup at the counter.
• Best for: roaming suits trips of 1–2 days or emergencies. A local SIM suits most travelers on medium to long stays.

Wi-Fi and Pocket Wi-Fi: Can They Replace a SIM?

Wi-Fi is easy to find. Nearly every hotel and guesthouse, from budget hostels to luxury properties, offers it free. Most cafes, restaurants and bars do too. Ask the staff for the password, or look for a sign. Hanoi, Ho Chi Minh City and Da Nang airports offer free public Wi-Fi, though it can be slow or require registration. Speeds are generally good in cities, but they can drop at peak times or in crowded venues.

The gap is in between. Secure, fast public Wi-Fi outside specific venues is limited, and many open hotspots are unsecured. Avoid logging into banking apps on them. More importantly, you cannot hail a Grab, check a map or translate a menu while walking between cafes if you only have Wi-Fi. Think about booking a train, too: a Hanoi to Da Nang soft-sleeper ticket costs 900,000–1,500,000 VND (36–60 USD) depending on the train and season, and you can check schedules and book on dsvn.vn or vietnamrailways.com.vn. Doing that on the go needs mobile data.

Pocket Wi-Fi is a middle path. You can rent a device at international airports or through online agencies such as Klook and local providers. Prices run 75,000–150,000 VND (3–6 USD) per day for unlimited data under fair use. It connects several devices, which suits groups. The downsides are one more device to charge and carry, the risk of loss or damage, and a deposit. For solo travelers and couples, a SIM or eSIM is usually cheaper.

What Has Changed Since 2024

• Stricter SIM registration. Since late 2023 and early 2024, the government has pushed harder to link every SIM to a registered identity. Buying a SIM now almost always means a passport scan and sometimes a quick photo, even for tourist SIMs. Unregistered SIMs can be deactivated. There have been discussions and pilots about collecting biometric data such as fingerprints. It is not universally enforced for tourists, but it is a possibility, so a passport scan and photo remain the standard for now.
• More 5G. 5G coverage has expanded considerably in Hanoi, Ho Chi Minh City, Da Nang and Hai Phong. Tourist packages generally include 5G where available, as long as your phone supports it.
• eSIM goes mainstream. All three carriers now offer eSIMs, and availability and promotion have grown significantly since 2024.
• Better Wi-Fi and more rental options. Internet infrastructure keeps improving, and the pocket Wi-Fi market has matured with more providers and competitive pricing.
• Roaming has barely moved. Some carriers have added regional passes or adjusted prices, but roaming remains more expensive than local options.

Common Mistakes to Avoid

• Leaving data roaming on. Even if you plan to use a local SIM or eSIM, switch off roaming on your home line. Background updates add up fast at 250,000 VND (10 USD) per MB.
• Buying from an unregistered seller. A cheap SIM with no passport check can be deactivated later. Insist on proper registration.
• Skipping the test. Check data, calls and SMS at the counter. Fixing a dead SIM is far easier before you have walked away.
• Choosing by price alone. A Mobifone or Vinaphone plan is great in cities, but if you are heading to remote areas, Viettel’s wider coverage is worth the extra few thousand dong.
• Ignoring the fair usage policy. “Unlimited” plans throttle after a daily cap, such as 3GB for Viettel’s unlimited pack. Heavy video users should check the cap.
• Assuming your phone supports eSIM. Check the compatibility list before you plan around it.
• Trusting prices you read online. Package names and prices change often. Ask what is on offer when you arrive.

Frequently Asked Questions

Is a local SIM cheaper than international roaming in Vietnam?

Yes, in almost every case. Roaming day passes run 250,000–500,000 VND (10–20 USD) per day, while a 30-day Vietnamese tourist SIM costs roughly 300,000–350,000 VND (12–14 USD). Only a stay of one or two days makes roaming competitive.

Do I need my passport to buy a SIM card in Vietnam?

Yes. Passport registration is a strict government requirement. Staff will scan or copy it and may take a quick photo. Unregistered SIMs can be deactivated, so avoid sellers who skip registration, even when the price looks tempting.

Can I use an eSIM from Viettel, Mobifone or Vinaphone?

Yes. All three offer eSIMs for compatible phones, such as iPhone XS/XR and newer, Pixel 3 and newer, and Samsung Galaxy S20 and newer. You buy at an airport or official store and scan a QR code. Prices generally match physical SIM packages.

Which Vietnamese network has the best coverage?

Viettel has the widest coverage, especially in rural and remote areas, and is generally seen as the most reliable. Mobifone and Vinaphone are strong in cities and tourist spots. If you plan to trek or ride through the countryside, choose Viettel.

Can I keep my home number while using a Vietnamese SIM?

Yes, with an eSIM. Keep your home SIM active in one slot for calls, texts and two-factor codes, and use the Vietnamese eSIM for data. Switch off data roaming on the home line to avoid surprise charges.

---

📷 Featured image by Bùi Đạt on Unsplash.