How to Transfer UK SIM to a Different Phone

Why You Might Need to Transfer Your UK SIM

There are many reasons to transfer a UK SIM to a different phone. You may have upgraded to a new device, your current phone broke, you want to use a dual-SIM setup in Pakistan, or you need to switch to an eSIM-compatible phone. Whatever the reason, the process is straightforward — but there are important details to get right.

According to a 2025 mobile industry survey, 68% of smartphone users in Pakistan switch devices every 18–24 months. Of those who use international SIMs, approximately 43% report issues when first moving their SIM to a new phone, usually related to APN settings or roaming configuration.

Data from UK mobile networks shows that over 2 million roaming connections from Pakistan are made annually on UK SIMs. The most common support query from Pakistani users relates to SIM transfer between devices, accounting for 27% of all international roaming support tickets.

Physical SIM Transfer: Step by Step

Transferring a physical UK SIM is the simplest method. Follow these steps:

1. Turn off both phones — Always power down devices before handling SIMs
2. Locate the SIM tray — Use the eject tool or a paperclip to open the tray
3. Remove the SIM — Carefully take the SIM from the old phone
4. Check SIM size — Ensure the SIM fits the new phone's tray (see sizing section below)
5. Insert the SIM — Place it in the new phone's tray and close it securely
6. Power on the new phone — The SIM should register on the network automatically
7. Enable data roaming — Go to Settings > Mobile Network > Data Roaming and enable it
8. Test OTP reception — Send a test SMS or request an OTP to confirm everything works

SIM Sizes: Which One Fits Your New Phone?

UK SIM cards come in three sizes. Most SIMs from BUY UK SIM are multi-size (tri-cut) and can be adapted to any tray:

Most SIMs sold by BUY UK SIM are pre-cut as nano-SIMs with adapters for micro and standard slots. If your SIM is too large for the new phone's tray, do not cut it yourself — use a proper SIM cutter or ask your seller for guidance.

eSIM Transfer: What You Need to Know

If your UK SIM is an eSIM (digital SIM), the transfer process is different. eSIMs are tied to a specific device. To move an eSIM to a new phone:

• Giffgaff: You cannot currently transfer a Giffgaff eSIM to a new device. You would need to order a new eSIM or request a physical SIM instead
• Smarty: eSIM profile can be re-downloaded on a new device via the Smarty app or website
• VOXI/Vodafone: Log into your account, deactivate the old eSIM, and generate a new QR code for the new phone
• EE: eSIM transfer is available via the EE app or by contacting customer service

For most Pakistani users, a physical SIM is more practical as it can be moved freely between devices without contacting the network.

Reactivation: What If Your SIM Does Not Connect?

Sometimes a UK SIM may not automatically register on the new phone, especially when used outside the UK. If this happens:

1. Check roaming is enabled — Go to Settings > Mobile Data > Data Roaming (must be ON)
2. Set APN correctly — For Giffgaff: APN = giffgaff.com, username/password = blank
3. Manual network selection — Go to Network Operators > Search > Select Jazz or Zong manually
4. Restart the phone — A full reboot often resolves registration issues
5. Wait 5–10 minutes — Some networks take a few minutes to register a SIM in a new device
6. Test the old phone — If the SIM still works in the old phone, the issue is with the new device

APN Settings by UK Network

Dual SIM Considerations

Most Pakistani smartphones support dual SIMs. If you plan to use your UK SIM alongside a Pakistani SIM (Jazz, Zong, Telenor, Ufone), follow these guidelines:

• Set UK SIM as secondary (data roaming): Enable roaming specifically for the UK SIM slot
• Default SIM for SMS: Set the UK SIM as the default for SMS to ensure OTPs arrive on that number
• Data source: You can use your Pakistani SIM for data and keep the UK SIM for OTP-only — incoming SMS is free
• Call forwarding: If you want to receive calls on your Pakistani number, set up call forwarding from your UK number

Frequently Asked Questions

• Can I move my UK SIM to a different phone?

  Yes. Physical UK SIMs can be moved to any compatible unlocked phone. Simply remove the SIM from the old device and insert it into the new one. The SIM may automatically reconnect within a few minutes. If it does not, follow the reactivation steps in this guide.

• Will my UK number change if I switch phones?

  No. Switching phones does not change your UK number. The phone number is stored on the SIM card itself, not on the phone. Your +44 number remains the same regardless of which device the SIM is inserted into.

• Do I need to contact my UK network to transfer my SIM?

  For physical SIM cards, no — you can simply move the SIM to any phone. For eSIMs, you may need to contact the network to transfer the eSIM profile to a new device. For pre-activated SIMs from BUY UK SIM (Giffgaff), no network contact is needed for physical SIM transfers.

• What if my UK SIM stops working after changing phones?

  If your UK SIM does not work after switching phones, try: 1) Checking APN settings for mobile data, 2) Enabling data roaming in settings, 3) Restarting the phone, 4) Cleaning the SIM contacts, 5) Testing the SIM in the original phone to confirm it still works. If none of these help, contact your network or the seller.

• Can I use the same UK SIM in two phones at once?

  No. A physical SIM card can only be in one phone at a time. Some UK networks offer multi-SIM options (e.g., Giffgaff's additional SIM feature) that allow the same number on multiple devices, but this requires separate SIM cards and is not available on all networks.

UK SIM کو دوسرے فون میں منتقل کرنا بہت آسان ہے۔ صرف SIM نکالیں اور نئے فون میں لگائیں۔ آپ کا +44 نمبر وہی رہے گا۔ اگر SIM کام نہ کرے تو ڈیٹا رومنگ آن کریں اور APN سیٹنگز چیک کریں۔ BUY UK SIM سے 1,999 روپے میں پری ایکٹیویٹڈ SIM حاصل کریں جو کسی بھی فون میں چلے۔