SIM cards connect your device to the mobile network, giving you access to calls, texts, and data. This guide explains the difference between SIMs and eSIMs, how to order and activate them, and what to do if you run into issues.

What is a SIM?

• SIM card (physical): A small, removable chip you insert into your device.
• eSIM (embedded SIM): A digital SIM built into newer devices. Unlike a physical SIM, it can’t be swapped — you need to re-activate it each time you move to a new handset.

⚠️ SIMs and eSIMs are available with Mobile and Mobile Broadband (MBB) tariffs only. They are not supported for devices such as smartwatches.

Ordering a new SIM or eSIM

• New SIM card: Order through your plan partner.
• New eSIM: Order directly via my.plan.

Activating your SIM or eSIM

You can activate any SIM type through my.plan:

1. Log in.
2. Go to Controls → SIM Controls → SIM Swap.
3. Follow the step-by-step instructions.

Activation can take up to 24 hours but usually completes much quicker. Once active, restart your device to refresh the connection.

Troubleshooting SIM problems

If your device shows “Insert SIM” or the SIM isn’t working:

• Remove the SIM, restart your device, then reinsert.
• Check your APN settings (important if you’re on the O2 network). See the APN settings guide.
• Test the SIM in another device, if available.
• Check network status using your postcode:
  • plan Network coverage
  • O2 Network status
  • Ofcom mobile checker

If you’re having issues with calls or SMS, note any error messages — these details will help support teams investigate faster.

Common SIM issues

• Lost SIM: A replacement must be ordered from us — SIMs from other providers (like O2 directly) will not work.
• Wrong size SIM: All SIMs supplied are triple-cut (standard, micro, nano). Snap down to the size that fits your device.

SIM misuse policy

SIM misuse is prohibited, including:

• SIM boxes or gateways for bulk SMS
• Sharing one SIM across multiple devices

Such misuse may lead to termination of service.