Why Chinese Users Buy a giffgaff UK SIM Card
People who use Codex, X, GitHub, Claude and Google Cloud together eventually run into phone verification while registering an account, changing devices or recovering access. Codex itself can use ChatGPT sign-in or an API key and does not specifically require a UK number. The value of a UK mobile number is broader: it gives the owner a number that can remain available for overseas accounts, ordinary texts and future recovery attempts. An activated giffgaff SIM supplies a real UK mobile number that works for calls, texts and data in the UK and can roam on partner networks in China.
On this page
The problem with a temporary number appears months later
A temporary number may work on registration day, but the risk appears when the account asks for the same number after a device change or password reset. By then, the old message record may be gone and the number may have been reassigned.
A giffgaff number controlled by the account owner can stay in a phone and move to another compatible handset with the physical SIM. If a platform accepts the UK number and sends a message, the same line remains available to receive it.
Important accounts should still use an authenticator or passkey and keep recovery codes. SMS is one recovery path, not the only one, so losing a SIM does not have to lock every account at once.
The UK number can receive ordinary texts in China
giffgaff supports international roaming in China through partner networks. Its current China roaming page lists incoming standard texts as free, so the line can sit in a spare phone without a monthly plan when the main job is receiving messages.
Turn data roaming off if the line is only for texts. Calls, outgoing texts and pay-as-you-go data use airtime credit, while background apps can consume data without an obvious action. China travel data add-ons are available in the giffgaff app, but ordinary UK plan data does not cover China.
Incoming texts alone do not keep the number active. Within each six-month period, make a qualifying call, send an ordinary SMS or MMS, use mobile data, or buy airtime credit or a plan. Long-term use outside the UK is also subject to giffgaff's service and fair-use rules.
Get the physical SIM before travelling to the UK
A student, business traveller or short-term visitor can receive the physical card before departure, understand activation and top-up in advance, then activate it for a UK number and O2-powered coverage after arrival.
The activated number can be shared with a school, landlord, local contacts and family. A suitable plan can then be chosen around actual UK calls, texts and data use.
For a short European trip where data is the only need, a travel eSIM may be enough. giffgaff makes more sense when a real UK number, ordinary texting and longer-term control matter.
Why a physical SIM appeals to users in China
Support for overseas eSIM profiles varies by phone model and sales region. A physical SIM is simpler when the phone has a card slot, is not network-locked and supports the required bands.
The card also moves easily between compatible phones. If a spare handset fails or loses power, the SIM can be inserted into another device without repeating an eSIM installation or transfer.
To prepare an unactivated giffgaff physical SIM before travelling, check the current LarkSIM giffgaff SIM options. The user still creates and controls the giffgaff account.
Check current LarkSIM availability
Review the current supply, activation boundary and support scope before ordering a physical SIM.
arrow_forwardView the giffgaff physical SIM