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Help with your sim

Getting the right sized sim

Standard, micro and nano sim
Sims come in three different sizes - standard, micro and nano. Most new devices use a nano sim, but whatever size you need, we've got you covered.

All the sims we send out can be used in any device. Whether it takes a standard, micro or nano sim, you just need to pop out the size that's right for you. If you're not sure which one you need, have a look at the instructions that came with your device.

Don't try and cut down your old sim, as you could break it or get it stuck in your device. If you need to use your nano or micro sim in an older device, you can get a free adaptor from an O2 store.

Swapping your sim
Just go to or text SWAP to 20220, to activate your new sim.

You'll need your original sim and number, as well as your new sim. You'll also need the serial number on the back of your sim – it's the long number beginning with 8944.

The sim swap can take up to 24 hours, but is usually done within an hour. Once you lose signal on your original sim, turn your device off, put your new sim in and turn it back on. If you need to, keep turning your device off and on until you get signal. Then you're ready to go.

If you upgrade in store, they can complete the sim swap for you.

Find out more about sim swap

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