eSIM QR code: how to scan it and what to do

When you buy an eSIM you are given a QR code, and that square of blocks is the whole plan. Scanning it is the installation. Everything else is preparation and troubleshooting.

Đọc 4 phútThông tin được kiểm tra ngày 25 tháng 9, 2026

A paper-cut collage of a phone held over a paper card printed with an abstract pattern of blocks, on a hotel desk beside a closed passport, a boarding pass with no writing and a pen, in soft lamp light.

Trả lời ngắn

An eSIM QR code encodes the plan’s activation code. You scan it from the phone’s own settings, usually under Add eSIM or Add cellular plan, and the plan installs in seconds. It is single use, so it should not be shared, and if scanning fails the same details can be typed in by hand.

Trong bài này
  1. What the code actually contains
  2. Where it arrives
  3. How to scan it
  4. When scanning does not work
  5. Why you should not share it
  6. Keeping the code afterwards

A QR code looks like a link, and it is easy to treat it as one. It is closer to a key. It carries the details a phone needs to fetch one particular plan from one particular server, and using it is the installation rather than a step towards it.

That is why it is single use, and why the small practical decisions around it matter more than they seem to.

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Nguồn: GSMA: eSIM

What the code actually contains

An eSIM activation code has three parts: a format marker, the address of the server that holds the plan, and a matching identifier that points at your plan on that server. The QR code is those three parts written in a form a camera can read.

Nothing in it is a password in the usual sense. It is a claim ticket. Anyone holding it can claim the plan, which is the reason for every piece of advice below.

Một hình minh họa giấy cắt mã QR với các khối vuông bay lên, tia sáng từ camera chiếu xuống.

Where it arrives

Two places, and you should make sure both are usable before you travel.

The first is the screen, at the moment of purchase. The second is email, and the email is the one that matters later, because it is where the server address and activation code live in text form.

Save both to the phone before you go. A screenshot of the QR code, kept in your photos, works when the email will not load. What does not work is arriving at an airport with no data, an email app that needs a connection, and a code you have never seen.

How to scan it

The installation lives in the phone’s settings, not in the camera app, and this is the step people get wrong.

On an iPhone, open Settings, then the mobile data section, and look for the option to add an eSIM or cellular plan. On Android the path is similar: Settings, then the network or connections section, then SIMs, then add an eSIM. Either way the phone offers to scan a code or to enter the details by hand.

Point the camera at the code and wait. The phone reads it, contacts the server, and installs the profile. You will be asked to name the new line, which is worth doing properly, because a line called Travel is easier to find at midnight than one called Secondary.

Từ lúc mua đến khi có mạng

  1. Tại điểm bán

    Bạn thanh toán, gói cước được giữ lại

    Chưa có gì được cài đặt. Gói cước đang nằm trên máy chủ, chờ điện thoại xác nhận về nó.

  2. Chỉ trong vài giây

    Mã đến với bạn

    QR code hiển thị trên màn hình và gửi qua email với địa chỉ máy chủ, mã kích hoạt đi kèm. Hãy lưu chỗ nào có thể truy cập không cần mạng.

  3. Ở nhà

    Bạn quét mã

    Trong cài đặt điện thoại, ở mục thêm gói cước. Điện thoại kết nối đến máy chủ, tải profile và thêm dòng mới. Dòng mới mặc định chưa bật.

  4. Sau khi đáp

    Bạn bật dòng mới

    Bật dòng du lịch và dùng cho dữ liệu. Gói cước chỉ bắt đầu đếm từ bước này, không phải lúc bạn cài đặt.

When scanning does not work

Three things go wrong most often, and none of them means the plan is lost.

The first is a dirty or badly lit code. A code on a screen with the brightness turned down, or a printout that has been folded, can be unreadable. Turn the brightness up, or hold the phone further away.

The second is a phone that will not accept the code at all, usually because it is locked to a network. That is a phone problem, not a code problem, and it cannot be fixed by scanning harder.

The third is the code having already been used. If you scanned it once and the install failed halfway, the plan may already be claimed. Contact the company that sold it, because they can see the state of the plan and can usually issue it again.

If the camera simply will not cooperate, type the details in. Every eSIM comes with a server address and an activation code next to the QR code, and the manual option takes both. It is the same installation by a slower route.

Why you should not share it

Do not post a screenshot of your QR code in a group chat asking whether it looks right. Do not send it to a friend so they can read it out to you. Do not photograph it and leave it in a shared album.

The reason is that the first phone to install it gets the plan. There is no second factor and no confirmation step. Someone with the code and an unlocked phone can take the plan before you do.

The same applies to the text version. If you post the server address and matching identifier anywhere public, you have posted the plan.

Keeping the code afterwards

Once the plan is installed and working, the code has done its job. Keep the email anyway, because it is the record of what you bought and when, and it is what a support conversation will ask for.

Delete nothing until the trip is over and you have checked that the plan finished as expected. A code that has been installed cannot be reused, but an order email is still evidence, and it is much easier to resolve a problem with it in hand.

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Chuẩn bị các mục sau
Sau đó kiểm tra

If you would rather understand the technology before you buy, what an eSIM is covers it from the beginning, and eSIM against a physical card deals with the choice between the two.

Du khách thường hỏi

Where do I find the QR code after buying?

It arrives by email, and with us it is also shown on screen the moment payment completes. Save it to the phone before you travel, because the email is no use in a taxi with no data. A screenshot in your photos is enough.

Can I scan the same QR code twice?

No. The code installs the plan once, and the first phone to use it gets it. A second scan will either fail or install nothing. If you need the plan on a different phone after installing it, ask the company that sold it to reissue the code.

What if the camera will not read the code?

Type the details in instead. Every eSIM comes with two pieces of text alongside the QR code: the server address and the activation code. Choose the manual entry option in the same place you would scan, and enter them. It is the same plan by a longer route.

Should I install the eSIM before or after I arrive?

Before, and at home on wifi. Installing does not start the plan, so you can install it a week early and switch the line on when you land. Doing it at home also means the QR code is on a screen you control rather than in an email you are trying to open on airport wifi.

Nguồn

Thông tin được kiểm tra ngày 25 tháng 9, 2026

  1. GSMA: eSIM
  2. Wikipedia: eSIM
  3. GSMA: eSIM solutions and impact