The SIM card is your device's ticket to the T-Mobile network!
- Your SIM card is linked to your phone number, and it connects you to T-Mobile. It's not a memory card or SD card.
- Your SIM card can be easily moved from your current phone into another compatible phone to transfer your service.
- Check your device to find out the SIM size (See the "Tech specs" page), how to insert it, and how to set up SIM security.
- T-Mobile devices support three SIM sizes. If your device needs a different size, see Buy a SIM card.
- Nano SIM: The smallest SIM, most likely to be found in new devices.
- Micro SIM: A medium SIM, normally used in previous model devices.
- Standard SIM: The largest SIM, aka Mini SIM, found in older devices.
- T-Mobile SIM cards comes with adapters to work in devices that require nano, micro, and standard SIMs.
- Limited devices on our network support eSIMs using the T-Mobile eSIM app.
- We strongly suggest that you change or update your Customer PIN/Passcode to protect your account.
T-Mobile SIM cards come with adapters, in case your device uses a nano, micro, or standard card.
- Postpaid accounts: See our SIM card page to check prices or order online. You can also find one in a T-Mobile store.
- Prepaid accounts: See the Prepaid SIM Card page to check prices or order online. You can also stop by a store.
If you're using a device from another wireless provider, you first need to contact that provider to request a SIM unlock on the device.
To activate an unused T-Mobile SIM card:
- Log in to my.t-mobile.com, select the line, and click Phone > Change SIM. This online option is available only to postpaid, and only for physical SIM cards.
- Contact us or stop by a store. For your security, the account holder or an authorized user must make the request.
- If you're changing to an eSIM on a postpaid account, you'll need to use the QR code to download your eSIM settings after you contact us.
- If you want to activate an iPhone eSIM on a prepaid account, download the T-Mobile eSIM app.
If a SIM PIN security code has been entered incorrectly multiple times, the SIM will lock and require you to enter a PUK code to use your device again.
- Be careful!
- If you incorrectly enter your PUK code 10 times, your SIM will need to be replaced.
- Moving your SIM to another device will not fix this error.
- The PUK is unique to your SIM card. To get the code, you need to either:
- Contact us online or with another phone. For your security, you must be the account holder or authorized user to verify.
- Use the PUK Code printed on the card your SIM came in. Make sure the SIM card number matches the card.
- Once you have the PUK code, follow the instructions for your Device to enter it.
- "Contact your service provider'
- 'Insert SIM' or 'Invalid SIM'
- 'Unregistered SIM'
If you receive any of these errors:
- If using a non-T-Mobile device, make sure it is SIM unlocked. Contact the original provider if you need help.
- Turn off the device.
- Remove the SIM card from the device. For steps on how, visit the Devices page.
- Re-insert the SIM card snugly in the SIM slot.
- Turn on the device.
- If you're able to register on our network, the error should no longer appear.
- Perform a manual network selection, and try to register on the T-Mobile network.
- If available, move the SIM card to another T-Mobile device and test if it works or not. This test will help Customer Care diagnose the problem.
- If the error continues, use another device or online option to contact us.