What is an International Travel SIM? How to Buy and Use It

Switching your SIM card is one of the essential tasks when traveling or working abroad. Many people find it confusing when looking for a suitable international SIM while overseas. To better prepare for switching to a travel SIM and enjoy a smoother trip, let’s explore with Vietjet what a travel SIM is and where to buy one in the article below!

1. What is a Travel SIM?

A travel SIM, or international travel SIM, is a pre-activated SIM card that works in one or more specific countries. With an international travel SIM, you can make calls, send messages, and use mobile data in the supported country without needing to buy a local SIM card there.

The keyword “What is a travel SIM” is commonly searched by travelers preparing for trips abroad.

2. Types of International Travel SIMs

There are many terms like international SIM, roaming SIM, or multi-country SIM, which can be confusing. Here’s how you can easily distinguish them:

International travel SIMs are commonly divided into two main types:

Single-country travel SIM: This type is used in one country only and doesn’t require roaming registration. It won’t work in Vietnam; you’ll need to buy a new SIM when moving to another country.
International roaming SIM (multi-country SIM): This uses a Vietnamese number with international roaming enabled. Your number remains the same even when abroad. It’s convenient but generally more expensive.

Based on form, there are two SIM types:

Type	Physical International SIM	Travel eSIM
When to buy	Order 2–3 days in advance (in Vietnam), 4–5 days (abroad)	Buy online anytime. Receive QR code instantly.
Supported devices	All devices with physical SIM slots	Modern smartphones with eSIM support

Based on the comparison:

Travel eSIMs are more convenient and compact, ideal for frequent international travelers.
For short-term trips to one country, both physical SIMs and eSIMs are suitable depending on your needs and budget.

Besides physical SIMs, eSIMs provide a more convenient and time-saving option.

3. Where to Buy a Travel SIM?

3.1 Buy at the Arrival Airport

You can purchase a travel SIM after arriving at your destination — in the airport or local telecom shops. However, this can be time-consuming and problematic.

Buying a SIM abroad may require registration, passport verification, and filling out forms. For seasoned travelers, this isn’t a big deal, but for first-timers, it can be confusing and delay your trip. Sharing your passport with unknown vendors may also pose privacy risks.

Moreover, language differences may be a barrier. If the SIM guide is not in English, you might struggle to follow the activation steps.

Buying a SIM at the airport may cause issues for travelers unfamiliar with international procedures.

3.2 Register for an International SIM Online

To switch to a travel SIM without buying a new one, you can activate international roaming on your current Vietnamese SIM. This is faster and more convenient — you can do it from home or abroad with just a few taps.

Step 1:Use your current mobile number and contact your carrier to enable international roaming.

In Vietnam: Contact your provider via hotline, app, website, or visit a physical store.
Abroad: Log in to your provider’s website or app and register for international roaming.

Step 2:Once roaming is activated, turn on "Roaming" in your phone settings — your international travel SIM is now ready to use.

3.3 Buy an International Travel SIM in Vietnam

If you don’t want to use roaming, you can buy an international travel eSIM. There are many local and global eSIM providers available.

It’s best to purchase from Vietnamese sellers so you get better support and instructions in Vietnamese. Reputable sellers partnered with major carriers offer warranties and after-sales support.

After purchasing your data plan and completing payment, you’ll receive a QR code via email along with instructions to install and activate the eSIM. You should scan the QR code one day before departure to activate the eSIM on your device. Once abroad, it automatically connects to the supported network.

If you’re unsure where to buy, try Vietjet’s 4G eSIM. Vietjet not only offers affordable flights but also international 4G eSIMs for travelers.

Plans start at just 199,000 VND, providing high-speed internet access in over 200 countries worldwide. Check the full purchase guide HERE.

Vietjet offers affordable 4G eSIM plans for travelers from only 199,000 VND.

We hope this article helps you understand international travel SIMs and prepares you better for your trip abroad. To save time and money, don’t forget to book affordable international flights with Vietjet.

Vietjet operates many direct international flights to top destinations around the world with competitive fares and services. Especially exciting is their 0 VND international ticket promotion!

The “flash sale” 0 VND international ticket deal runs daily from 12:00 to 14:00. See details HERE!