To move your phone number to a different SIM card or activate a new SIM, you'll need to know your SIM number. It's written on the SIM card itself, but some phones let you find it from the settings menu too. Here's how…
Finding the SIM number in settings
Older Android phones will show you the SIM number in your settings menu, so you don't need to remove your SIM card to read it. If you can't find your SIM number by following the steps below, click here to download an app for finding your SIM number (often called an ICCID), or click here to find your SIM number from the SIM card.
Open your Apps list and tap on Settings. Scroll to the bottom of the menu and press About.
Tap Status. On some phones like HTCs, this may be called ‘Phone Identity’.
Tap IMEI Information.
Your SIM number will show as either the 'IMSI' number, or the 'ICCID number'. You can use this number when talking to your mobile network provider.
Can’t find your SIM number?
If you can't see your SIM number in the settings menu, you'll need to take the SIM card out of the phone and read it from the card directly. It's usually written on the plastic side.
If you still can't find your SIM number, you may have to call your network. This is the company who provide your SIM card, and their contact details can be found on your monthly bill. Here are the contact numbers for some of the most common UK mobile networks, just in case you get stuck:
EE - 0800 956 6000
o2 - 0344 809 0202
Three - 0333 338 1001
Vodafone - 03333 040 191
Virgin Mobile - 0345 454 1111