What's the difference between a standard SIM, micro-SIM and nano-SIM?
There are now three different sizes of SIM you might need to use, depending on your device: a standard SIM, micro-SIM or nano-SIM. We'll send you the right SIM for your phone when you take out your contract or upgrade with us.
If you're using a device that you didn't get from Three, you may not have the right sized SIM for your device to work. If that’s the case and you’re a Pay Monthly customer, you can order a replacement online. If you’re a Pay As You Go customer, you can visit a Three Store or contact us to order a replacement SIM.