Learn what an eSIM is, its key features and benefits, its pros and cons, which devices support it, how to install and activate it, and how to switch from a physical SIM to an eSIM.
eSIM technology was first introduced by Google in 2017, but it only really took off when Apple adopted it in the iPhone XS, XS Max and XR.
Summary:
- An eSIM (digital SIM) is a chip built into the circuit board of a mobile device (phone, tablet, smartwatch, etc.), so there is nothing to insert or remove like a physical SIM.
- Only phones with built-in eSIM support can use an eSIM.
- There are 2 ways to install an eSIM: scan a QR code or enter the details manually.
- To switch from a regular SIM to an eSIM, you can visit a carrier store or do it online in the carrier's app (depending on the carrier) — all 3 major Vietnamese carriers now support online conversion.
- Above all, an eSIM is more convenient and more secure than a physical travel SIM or international roaming when you travel abroad. You buy, install and activate it entirely online. Just note that you need an Internet connection to install an eSIM.
What is an eSIM?
An eSIM (embedded SIM) is a digital SIM built directly into your phone's circuit board, so there is no card to insert or remove. An eSIM is tiny (2.3mm long, 2.5mm wide and 0.2mm thick) and is set up by scanning a QR code or entering an activation code manually — no store visit required.
What are the pros and cons of an eSIM?
eSIMs have 5 main advantages: no physical SIM tray needed, better security, easy carrier switching, the ability to store multiple eSIMs, and the convenience of buying and activating online when you travel. The downsides are limited device compatibility, dependence on your device's condition, and the hassle of moving between devices.
Here is a closer look at the pros and cons of eSIMs:
1. Advantages of eSIM
- No physical SIM tray: Because it is built into the device, you never need a SIM ejector tool. This reduces the risk of losing or damaging your SIM.
- Better security: eSIMs are protected by advanced technology, reducing the risk of attacks or identity fraud.
- Easy carrier switching: An eSIM lets you change carriers and plans quickly without swapping cards like a regular SIM.
- Multiple eSIMs: You can install several eSIMs on one device, although how many can be active at the same time depends on the model.
- Convenient for travel: When you travel abroad, you can easily buy, install and activate an eSIM online from home, without visiting a store or waiting for a SIM to be delivered.
2. Disadvantages of eSIM
- Limited device support: Only phones with built-in eSIM technology can use one. Some models made for specific markets may differ in eSIM compatibility, so check carefully before deciding to use an eSIM.
- Harder to switch devices: Moving an eSIM to another device can be a bit more complicated than moving a physical SIM, especially when switching between carriers. You may need to visit a carrier store to transfer it to your new device.
- Dependent on your device: If your device has a problem, you may not be able to use your eSIM until it is repaired.
Can you use an eSIM in Vietnam?
Yes. Vietnam has adopted eSIM technology along with many other countries and territories around the world. The service officially launched in Vietnam in 2019, and today all the major carriers — Viettel, VinaPhone and MobiFone (as well as virtual operators such as Wintel and iTel) — support eSIM.
For international travel, eSIM plans are available for popular destinations among Vietnamese travelers such as Thailand, Japan, South Korea, the US and Europe — see the full list on TouriESIM's destinations page.
Is an eSIM more expensive than a physical SIM?
No. Converting a physical SIM to an eSIM in Vietnam currently costs only about 15,000–25,000 VND per SIM, depending on the carrier (reference prices, subject to change). Travel eSIMs are also very competitively priced compared with physical SIMs offering the same data, while being more convenient and more secure.
For example, on a short trip to Singapore, a travel eSIM plan usually costs about the same as a physical SIM with the same data allowance, but the eSIM offers far more value thanks to its convenience (nothing to swap, buy online and receive it instantly) and better security for your device. You can check plan prices on the Singapore eSIM page.
Should you use an eSIM when traveling abroad?
Yes, absolutely! An eSIM is usually much cheaper than international roaming and more convenient than a physical SIM, since you don't need to swap cards or hunt for a shop at the airport. Simply buy your eSIM online before you leave, receive the QR code by email, scan it, and you'll be connected as soon as you land.
Where can you buy a travel eSIM quickly and reliably?
Consider TouriESIM — data-only travel eSIMs for many countries and regions, including single-country plans, regional plans and a Global plan. TouriESIM's advantages include:
- A wide range of plans: Daily plans, fixed-data plans and unlimited plans (depending on the destination), so it's easy to choose one that fits your needs and trip length.
- A simple process: Buy entirely online, receive your QR code by email after payment, and install it by scanning the code — no need to remove your main SIM.
- Dedicated support: A Vietnamese-speaking customer care team ready to advise you and resolve issues promptly and attentively.
Browse TouriESIM plans by destination on the destinations page and buy online in just a few minutes.
Which devices are compatible with eSIM?
A wide range of devices support eSIM, most commonly iPhone XS and later, Samsung Galaxy S20 and later, and Google Pixel phones. eSIM is also supported on many other devices such as smartwatches, tablets and laptops.
Here is a detailed list of eSIM-compatible devices:
- iPhone: iPhone XR, XS, XS Max, the entire iPhone 11, 12, 13, 14, 15, 16 and 17 lineups, and the SE models (2nd generation and later).
- Samsung: Galaxy S series (S20, S21, S22, S23, S24, S25, S26), Galaxy Z series (Fold and Flip), and the Note 20 series.
- Google Pixel: Pixel 2 and later (including the Pixel Fold).
- Oppo: Oppo Find X3 Pro and later, and the Find N series, depending on the market.
- Other devices: Huawei (P40, P40 Pro and later) and Xiaomi (12T Pro, 13 series and later) also support eSIM, depending on the market.
- Tablets: iPad Pro, iPad Air (3rd generation and later), iPad (7th generation and later), iPad mini (5th generation and later), and some 5G Samsung Galaxy Tab models.
- Smartwatches: Apple Watch (Series 3 LTE and later) and Samsung Galaxy Watch.
The quickest way to check whether your device supports eSIM is to go to Settings > Cellular. If you see an Add eSIM option, your phone is compatible.
► See the full list of the latest eSIM-compatible devices.
Note: eSIM compatibility also varies by market. For example, most iPhones made for mainland China and some models sold in Hong Kong and Macau do NOT support eSIM.
How do you switch from a SIM to an eSIM with Viettel, Vinaphone or MobiFone?
All 3 carriers let you switch online through their apps (Viettel: My Viettel, 25,000 VND fee; Vinaphone: My VNPT, 25,000 VND fee; MobiFone: My MobiFone, 15,000 VND fee — reference prices, subject to change) or in store (bring your citizen ID card and your old SIM).
1. Viettel
You can visit a Viettel Store (bring your citizen ID card and your old SIM) or do it online in the My Viettel app: Log in > Other utilities > Mobile utilities > Change to eSIM > verify your details > pay the 25,000 VND fee (deducted from your main balance; reference price, subject to change) > receive a QR code by email to activate.
2. Vinaphone
You can do it online in the My VNPT app: go to Mobile subscription > Support tools > Register eSIM > Convert physical SIM to eSIM > follow the instructions; the fee is 25,000 VND (reference price, subject to change). Alternatively, visit a Vinaphone store with your citizen ID card and your old SIM.
3. MobiFone
You can visit a MobiFone store (bring your citizen ID card and your old SIM; 25,000 VND fee), or do it online in the My MobiFone app: log in with your phone number + OTP > select Change to eSIM under Utilities > confirm the 15,000 VND fee > verify your identity (ID/portrait photos or OTP) > receive a QR code to activate (reference prices, subject to change).
How to install and use an eSIM
Installing an eSIM is simple and takes only 3–5 minutes. There are 2 ways: scan the QR code you receive by email, or enter the activation code manually. See also our eSIM installation guide and eSIM activation guide.
The steps differ slightly from device to device. See the detailed guides:
Note:
- Before installing, make sure your phone is eSIM-compatible and has a stable Internet connection throughout the installation.
- If you're using a travel eSIM, make sure your phone is carrier-unlocked. It's best to install your travel eSIM about a day before your trip; the plan's validity usually starts when the eSIM connects to a network (depending on the plan — see when your data plan starts).
Frequently asked questions
How many eSIMs can one phone hold?
You can install multiple eSIMs on one device, but how many can be active at once depends on the model. Some phones can store up to 20 eSIMs. On an iPhone, you can install 8 or more eSIMs and use 2 phone numbers at the same time.
Will resetting my phone delete my eSIM?
If you reset your phone and choose to erase all data (including eSIMs), the eSIM line will be removed, and you'll need to contact your carrier or provider to get a new QR code.
Can I use an eSIM and a physical SIM at the same time?
Yes. You can use both on the same device. See how to use an eSIM and your main SIM at the same time.
What should I do if my eSIM loses signal?
If your eSIM loses signal, you can quickly fix it by updating your phone's operating system, moving to an area with better coverage, or restarting your device. In Vietnam, you can also choose an eSIM from a carrier with wide coverage such as Viettel or Vinaphone to get better signal, even in remote areas.
Should I use the eSIM as my primary or secondary SIM?
With an eSIM as your primary SIM, you can use it for everything: calls, texts, mobile data, utilities and value-added services. However, some users experience signal drops on their eSIM. To avoid losing contact, you can keep your physical SIM as your primary line.
Does using an eSIM drain the battery?
Running an extra SIM on your phone will use slightly more battery than usual. However, the difference is negligible, so you can use it with peace of mind without worrying about your battery running out quickly.
Can I buy a travel eSIM online?
Yes. Installing and activating an eSIM is very easy, so you can buy one online from a reputable provider such as TouriESIM — choose a plan by destination and receive your QR code by email after payment.
Can a carrier-locked iPhone use an eSIM?
Carrier-locked iPhones cannot use a travel eSIM. When you scan the eSIM code, you'll see the message “Cellular plans from this carrier cannot be added”. You can check whether your phone is carrier-locked before you buy.
Can the same eSIM number be used on both a phone and a smartwatch at the same time?
You can sign up for the MultiSIM service to use multiple SIMs across several devices at once. This means your phone and smartwatch will share the same phone number.
If I've installed an eSIM, can I still use it when I travel abroad?
If your carrier supports international roaming, you can keep using your eSIM abroad. Contact your carrier for details. Alternatively, you can add a travel eSIM to use local data at your destination, which is usually much cheaper than roaming.
Can I switch my eSIM from one carrier to another?
Yes. Contact your current carrier to check your eligibility and get support, then proceed with switching your eSIM to the new carrier.
Can I use my eSIM if I lose the activation QR code?
You can't install an eSIM without its activation QR code. Visit your carrier's store or contact your eSIM provider and ask them to issue a new code.
How long can I use an eSIM?
With a domestic carrier eSIM, you can keep using it indefinitely unless you delete it from your phone. With a travel eSIM, you can use it until the plan expires or the data runs out.
Can I share mobile data with other devices when using an eSIM?
An eSIM works exactly like a physical SIM, so you can share mobile data with other devices as usual. See also: Can you use an eSIM as a WiFi hotspot?
Do Mobifone and Vinaphone support eSIM on Apple Watch and Samsung Galaxy Watch?
At the moment, Mobifone and Vinaphone do not yet support eSIM on smartwatches such as the Apple Watch and Samsung Galaxy Watch. You may want to consider a Viettel eSIM to keep these wearables connected.
