iPhone 16 vs iPhone 15 eSIM in Vietnam: What Changed?

Both the iPhone 15 and iPhone 16 support eSIM on all models sold for Vietnam — that means the global/AQ variants. There is no difference in hardware or carrier features introduced by Apple that specifically benefit Vietnam. The eSIM capabilities are essentially identical across the two generations.

US models of both iPhones ship without a physical SIM slot, but that is irrelevant for visitors to Vietnam because local eSIMs work perfectly on those devices. Vietnam models retain a single physical nano-SIM slot alongside eSIM support. Carrier compatibility with Viettel, Vinaphone, and Mobifone is identical between the iPhone 15 and iPhone 16 — no new bands or profiles were added.

Both generations support dual SIM in the same way: one physical SIM plus one eSIM, or two eSIMs on models without a physical slot (like US versions). For Vietnam, where the local models keep a physical tray, you can insert your home SIM for SMS and banking while using a Viettel or Vinaphone eSIM purely for data. This setup works identically on iPhone 15 and iPhone 16.

Apple did not change the dual‑SIM management UI with the iPhone 16 — it runs iOS 18, but the eSIM menus are the same as iOS 17 on the iPhone 15. One important limitation remains on Vietnam models: you cannot use two eSIMs simultaneously if a physical SIM is inserted, because the single SIM tray hardware restricts the phone to one active physical line at a time. This is not a new restriction; it applies to both generations.

Installing an eSIM on either iPhone is identical. Go to Settings > Cellular > Add Cellular Plan and scan the QR code provided by your eSIM provider. The process has not changed between iOS 17 and iOS 18, so anyone familiar with setting up an eSIM on an iPhone 15 will find the exact same flow on the iPhone 16.

Both models require a Wi‑Fi connection to activate the eSIM — this could be your home network or airport Wi‑Fi. A common practice is to install the eSIM before departure (scanning the QR while still connected to Wi‑Fi), but activation only completes once you connect to a Vietnamese carrier network. That means the eSIM will begin working as soon as you land, regardless of whether you pre‑installed it. The same rule applies to both phones.

Viettel, Vinaphone, and Mobifone all support eSIM on both iPhone 15 and iPhone 16 without any change. No new 5G bands or optimizations were added by Apple that would affect local coverage. The 4G and 5G bands used in Vietnam are already supported on iPhone 15, so coverage on the iPhone 16 will be identical.

Our plans from simvietnam — for example the Viettel 5GB/day 7-day plan or the Vinaphone 5GB/day 10-day plan — work identically on both iPhone generations. You can use the same eSIM profile, see the same data speeds (typically enough for maps, social media, and video calls in cities), and enjoy the same reliability. If you already have an eSIM installed on an iPhone 15, you can even transfer it to an iPhone 16 using Apple’s eSIM Quick Transfer.

One critical point that has not changed: iPhone 15 and iPhone 16 models sold in mainland China, Hong Kong, and Macau do not include eSIM functionality. This is a hardware limitation imposed by Apple for those regions. If you are traveling with a Chinese iPhone, you will need to use a physical Vietnam SIM — or borrow a phone that supports eSIM.

No software update can enable eSIM on these models. There is no workaround. Travelers from China, Hong Kong, or Macau should plan accordingly: either purchase a physical SIM upon arrival at the airport (Vietnam’s major carriers sell tourist SIMs) or bring a secondary device that supports eSIM. This limitation applies to both iPhone 15 and iPhone 16 equally.

If you already own an iPhone 15, there is zero eSIM benefit in upgrading to iPhone 16 for Vietnam travel. Both generations handle eSIM with identical performance and reliability. The activation process, carrier compatibility, and dual‑SIM management are all the same.

The only reasons to upgrade would be if you need the new camera system, the A18 chip, or other non‑connectivity features. For eSIM‑based internet access in Vietnam, your iPhone 15 is already fully capable. Save your money unless the camera or performance upgrades genuinely matter to you.