🇬🇧 Giffgaff SIM Card Activation and Number Preservation Ultimate Guide (2026 Edition)

For users frequently traveling between China and the UK, on international business trips, or needing to receive verification codes from abroad (such as for ChatGPT, PayPal, US Apple ID, etc.), having a long-term, stable, low-cost UK Giffgaff SIM card is undoubtedly a powerful tool for pay-as-you-go use.

Giffgaff is a well-known mobile virtual network operator (MVNO) in the UK, relying on the robust network coverage of O2. Its most attractive features include global free monthly rental for receiving SMS and, under certain pay-as-you-go use rules, the balance never expires.

To help you maximize the utility of this UK card, the MollySIM Team has specially prepared this 2026 Ultimate Guide for Giffgaff Activation, Number Preservation, eSIM Conversion, and Wi-Fi Calling Cost Reduction!

⚠️ Legal Safety Warning

📌 Important Note: The SIM card described in this guide is intended solely for overseas travel, international business, and legal pay-as-you-go use or receiving verification codes. Please strictly adhere to local laws and regulations. It is strictly prohibited to use this SIM card for any illegal activities; all consequences will be borne by the user!

I. Giffgaff Activation Steps

When you receive your Giffgaff physical SIM card, please choose the corresponding activation/login method based on the version you purchased:

📌 Option A: If You Purchased the "Pre-activated SIM (with preloaded balance, e.g., £10 or £15)"

If you purchased a pre-activated version with preloaded balance from MollySIM, our warehouse team has already completed all activation and balance top-up operations for you before shipping. Do not attempt to go to the official website for the complex paid activation process; simply follow these three easy steps to take over your SIM card:

Insert the SIM Card: After receiving the card, simply insert the Giffgaff physical SIM card into your phone. Wait for 1-5 minutes for your phone to roam and connect to a local partner network (such as China Mobile/China Unicom).
Obtain Your Phone Number:

Open your SMS app and send the message number to 2020 or 43430 (completely free).
Within a minute, you will receive a text from Giffgaff containing your UK phone number (e.g., 07xxx xxxxxx).

Reset and Take Over Your Account:

Open the Giffgaff login page in a web browser on your computer or mobile device.
In the account/phone number input box, enter the UK phone number you just received (please enter the full mobile number, including the leading 0, e.g., 07xxxxxxxxx, or the full format with country code +447xxxxxxxxx).
Click on "Forgot password/member name?".
Choose to receive the verification code via SMS.
Your phone will immediately receive a text with a reset link/verification code. Click the link to reset and set your new account password.
Congratulations! Your account has been successfully taken over, and you can now log in to view your £10 or £15 balance and use it normally!

📌 Option B: If You Purchased the "Unactivated SIM (requires self-recharge and activation)"

If you purchased a blank card with no preloaded balance, please strictly follow the steps below to pay for activation in a web browser on your computer or mobile device. Note: Do not insert the SIM card into your phone until activation is successful!

Go to the Official Activation Page:

Do not insert the SIM card; open the Giffgaff activation website in a web browser.
Enter the 6-digit activation code printed on the card sleeve or card, and click "Activate your SIM".

Enter Your Registration Email:

Enter your commonly used email (it is recommended to use an international email like Gmail or Outlook), and click "Next".

Complete Email Verification:

Log into your email and enter the 6-digit verification code you received, then click "Confirm".

Set Your Account Password:

Create your account password and click "Register" to complete account creation.

Skip Unnecessary Offers:

On the promotional offers or additional services selection page, choose "No, thanks", then click "Continue".

Select Pay-As-You-Go Plan (Key Step!):

⚠️ Important Note: During activation, the system will strongly recommend various monthly contract plans (Goodybags). If you are only looking to preserve your number at a low cost, scroll to the bottom of the page and select "Pay as you go" (zero-monthly-fee mode), then click "Continue".

Recharge for Activation:

Select the recharge amount of £10, and click "Pay now".
Payment can be made using international multi-currency credit cards (such as those with VISA or MasterCard logos).
Note: If you use a Giffgaff voucher for activation, you do not need to enter credit card information.

Fill in Billing Information:

Enter your name and address. It is recommended to use your real name in English and search for a real UK address and postcode using Google Maps to successfully pass the credit card's 3D secure verification. Click "Continue".

Submit Payment Order:

Enter your credit card number, expiration date, and security code (CVV), check "I understand and agree", and click "Place order" to submit.

Obtain Your UK Phone Number:

The system will allocate and display your exclusive phone number only after the SIM card is successfully activated and inserted into your phone. Once inserted, you can check your phone number via device settings, logging into the official console, or by sending a free SMS with text "number" to 2020.

Insert the SIM Card and Test:

At this point, you can return to the Giffgaff account homepage. If your £10 balance is displayed, activation has been successfully completed!
Now insert the physical card into your phone and wait for a signal (in China, it will usually roam to China Mobile or China Unicom's network). Activation typically completes within 30 minutes; in rare slow cases, it may take up to 1 hour, but no longer than 24 hours.

II. Tariff Details

Giffgaff's zero monthly rental pay-as-you-go tariffs during roaming in China are as follows:

Receiving SMS: Completely free 💸
Sending SMS: £0.30/message (after enabling Wi-Fi Calling, this can be significantly reduced to £0.08/message!)
Making Calls: £1.00/minute (after enabling Wi-Fi Calling, this can be significantly reduced to £0.03/minute!)
Receiving Calls: £1.00/minute

Data Packages (Not Recommended for Use While Roaming in China):

£12 / 1GB / Month
£24 / 5GB / Month
£36 / 10GB / Month
Purchase/Usage Method: If you are traveling in the UK or Europe, you can log into the Giffgaff App on your phone and select your destination country in the "My data" section at the top of the homepage to purchase.

III. Number Preservation Rules and Methods

The rules for preserving your Giffgaff number are extremely simple and cost-effective: As long as there is a change in account balance (i.e., spending or recharging) at least once every 180 days (approximately 6 months), your phone number and balance will automatically extend the validity period by another 180 days!

This means you only need to perform any of the following actions within every 6 months to easily preserve your number:

Send a Text Message: Send a text from your Giffgaff number to another international number (sending a text to a UK number from China only costs £0.30; if Wi-Fi Calling is enabled, it only costs £0.08!).
Use Mobile Data: Turn off Wi-Fi and enable cellular data to generate a few KB of traffic, incurring a small data charge.
Make a Call: Make any call that connects (charges will apply, excluding emergency services or customer service hotlines).
Recharge Your Balance: Recharge once on the official website.

Standard Format for Dialing and Sending SMS:

When making international calls or sending international SMS, the format is: + + Country Code + Phone Number.

To the USA: If the US number is 8888888888, enter the receiving number as: +18888888888.
To the UK: If the UK number is 7777777777, enter the receiving number as: +447777777777.

⚠️ Risk Control Safety Tips: When preserving your number in China, it is strongly advised not to call or send SMS to domestic +86 numbers. Currently, major domestic operators have implemented strict default interception mechanisms for overseas spam messages and harassment calls. Sending SMS to domestic numbers not only has a high probability of being intercepted by the system but may also trigger big data fraud risk control mechanisms, leading to your Giffgaff account being suspended. The safest method for pay-as-you-go use is to prepare two Giffgaff cards to send messages to each other or send messages to your own overseas virtual number (such as Google Voice).

IV. Common Tasks and Settings

To facilitate daily management, here are some commonly used self-service settings during your use of Giffgaff:

Check Your Phone Number: Edit a message with number and send it to 2020 or 43430. Usually, within 30 seconds to 2 minutes, you will receive a message containing your phone number, completely free.
Change Account Email: If you need to change your registered email, you can directly visit the Giffgaff email change page.
Reset Account Password: If you forget your password, click "Forgot your password?" on the official website and enter your registered UK phone number to reset your password (Note: When entering your phone number, you need to include the country code +44 or remove the leading 0).

V. Change Number

If you are not satisfied with the phone number randomly assigned to you by the system, Giffgaff offers a convenient self-service number change:

After logging in, open the Giffgaff number change page and click "Get a new giffgaff number".
Enter your account password and then click "Change my number".
The system will automatically redirect you to the settings interface. Wait a few minutes, and the system will randomly assign and display your new phone number.

🔔 Number Change Notes: Maintenance Time Limit: Due to system maintenance, number change requests cannot be submitted between 5:30 AM and 1:00 PM Beijing Time. Activation Delay: After a successful number change, the new number and balance may take up to 4 hours to fully activate in your account and mobile network. * Number Change Limit: It is recommended to perform the entire operation in a stable Wi-Fi environment. Each Giffgaff account supports a maximum of 2 self-initiated number changes, and the second change must be more than 24 hours after the first.

VI. eSIM Conversion Tutorial

If your device supports eSIM functionality (such as unlocked versions of iPhones or Android phones from the US or Hong Kong), you can seamlessly convert your physical SIM to eSIM online through the Giffgaff App, eliminating the hassle of keeping a physical card!

Pre-requisites for Conversion:

The device must natively support eSIM activation.
The latest version of the Giffgaff app must be installed on your phone, and you must be logged into your account.
The phone must be connected to a stable and reliable Wi-Fi network.
⚠️ Operation Time Window: Due to operator maintenance, please perform the conversion between 12:30 PM and 4:30 AM Beijing Time.

Detailed Conversion Steps:

Start the Conversion Process: Open the Giffgaff app on your phone, and sequentially click "Account" > "SIM" > "Replace my SIM" > "Switch to a new eSIM".
Confirm Risks and Start: Ensure the Wi-Fi signal is excellent, check "I understand and accept this", and click "Start the switch".
Verify Identity: Enter the SMS verification code received on your phone, or check your registered email for the code and enter it, then click "Confirm".
Download and Install eSIM: Click "Install eSIM" on the page, and the system will invoke the phone's native eSIM configuration program. Follow the on-screen prompts to complete the installation step by step.
Wait for Activation: The screen will display "We're activating your eSIM". Typically, it will be fully activated within 1 hour. Once the eSIM signal bars appear, the original physical card will automatically change to "No Service," and the physical card will become invalid.

VII. Enable Wi-Fi Calling for Ultra-Low Tariffs

Wi-Fi Calling is an incredibly powerful feature. With this feature, when your phone is connected to Wi-Fi, it communicates directly with the core network of Giffgaff in the UK via broadband. At this point, even if you are in China, all calls and texts will be treated as if you are using them in the UK, resulting in dramatically reduced costs!

💥 Wi-Fi Calling Reduced Tariff Comparison:

Sending SMS: Only £0.08/message (savings of 73%!)
Making/Receiving Calls: Only £0.03/minute (savings of 97%!)

🚀 Steps to Enable:

Network Support: Ensure your phone is on a stable Wi-Fi network (it is recommended to use a UK node IP globally).
Enable Wi-Fi Calling on iPhone:

Open "Settings" on your iPhone ➡️ Select "Phone" ➡️ Click "Wi-Fi Calling" ➡️ Toggle "Enable Wi-Fi Calling on this iPhone" to on.

Enable Cellular Data:

Open "Settings" on your iPhone ➡️ Select "Cellular" ➡️ Click on your Giffgaff number ➡️ Go to "Voice & Data" ➡️ Select "4G" or "5G".

Verify Activation Status:

After successful activation and connection to Wi-Fi, the carrier name at the top of your phone will change from the normal "China Mobile" or "China Unicom" roaming display to "giffgaff Wi-Fi".
Once you see this carrier logo, you can make calls and send texts at ultra-low UK domestic rates without any hassle!

Conclusion

As a low-cost overseas long-term pay-as-you-go use card, Giffgaff demonstrates unparalleled cost-effectiveness for receiving cross-border service verification codes and travel. We hope this ultimate guide helps you address all your questions regarding activation, tariff optimization, eSIM switching, and effective pay-as-you-go use.

If you have more questions about global business travel networks, travel physical cards, or high-quality, high-speed MollySIM eSIM plans, feel free to follow us and visit the MollySIM Blog regularly, where we will continue to provide you with the most professional, cost-effective, and efficient global network and digital solutions!✈️🇬🇧🌍