When traveling abroad, staying connected is one of the first things tourists think about. For modern travelers carrying the latest iPhones such as the iPhone 15, 16, or 17 series, using an eSIM is one of the most convenient and cost-effective ways to enjoy fast internet in Vietnam or any other country. However, not every iPhone will work with eSIM. This guide will help you check if your iPhone is compatible, explain why some iPhones cannot use eSIM, and highlight important exceptions like iPhones from Mainland China, Hong Kong, and Macao.

An eSIM (embedded SIM) is a digital SIM card built into your phone. Instead of inserting a physical SIM, you simply scan a QR code and instantly add a data plan. For travelers, this means:

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  No need to find a SIM card shop after landing.
  
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  Easy activation before departure.
  
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  Ability to keep your original number active while using local data.
  
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  Reliable connection on arrival with no roaming charges.
  

For iPhone 15, 16, and 17 users, eSIM technology is already integrated into your devices, making it the simplest solution for staying online abroad.

According to the latest eSIM-compatible devices list, the following iPhones are compatible:

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  iPhone 15 series: iPhone 15, 15 Plus, 15 Pro, 15 Pro Max
  
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  iPhone 16 series: iPhone 16, 16 Plus, 16 Pro, 16 Pro Max, 16e
  
• 
  iPhone 17 series (and newer models expected from 2025 onward)
  

Older models, from iPhone XS, XR, 11, 12, 13, and 14 series, also support eSIM. This means that if you own one of the latest iPhones, you should technically have no issue using an eSIM.

Even if your iPhone is on the compatibility list, there are cases where eSIM cannot be activated. The most common reasons are:

If you bought your iPhone under an installment plan or monthly contract from carriers such as T-Mobile, AT&T, Verizon, Vodafone, or similar, your phone might be network-locked.

• A locked iPhone means you can only use the eSIM provided by that specific carrier.
  
• You cannot install or activate a Vietnam eSIM until your carrier unlocks the device.
  
• Contact your carrier to request an unlock (conditions vary depending on payments and contract status).

Not all iPhones sold worldwide are the same. Apple designs models differently depending on the country:

• Mainland China iPhones: Do not support eSIM at all. All iPhone models bought in China only work with physical SIMs.
  
• Hong Kong & Macao iPhones: Most models do not support eSIM, with very few exceptions (like iPhone 12/13 mini, iPhone XS, and iPhone SE 2/3).
  

This is very important for travelers who bought their phones in these regions. Even if you own the latest iPhone 15, 16, or 17 from Mainland China, it will not work with eSIM.

Make sure your iPhone is updated to the latest iOS version.
If you don’t see the option to “Add eSIM” under Settings > Cellular/Mobile Data, your phone may either be locked or not supported.

Here’s a quick way to test before your trip:

1. Open Settings on your iPhone.
   
2. Tap Cellular or Mobile Data.
   
3. Look for the option Add eSIM or Add Cellular Plan.
   

• If you see this option, your device is compatible.
  
• If not, your iPhone is either locked or from a non-supported region.

If your iPhone supports eSIM, here’s why you should use it when visiting Vietnam:

• Instant Internet Access: Install before departure, so you land with working data.
  
• No Physical SIM Hassle: Avoid losing or damaging tiny SIM cards.
  
  Keep Your Main Number: You can receive SMS or calls from your home number while using local data.
  
• Multiple Plans: Easily switch between different data packages or countries if you travel around Asia.

If your iPhone is from Mainland China, Hong Kong, or Macao (without eSIM support), or if your device is locked, don’t worry—there are alternatives:

• Buy a physical SIM card upon arrival at Vietnam airports like Noi Bai (Hanoi) or Tan Son Nhat (Ho Chi Minh City).
  
• Use portable Wi-Fi devices (though less convenient).
• Ask your carrier if they can unlock your device before traveling.