You can only use one number at a time with your iPhone's Dual SIM. To switch between numbers, here are some simple steps to follow.
To change which number uses cellular data, follow these steps:
- Go to Settings.
- Tap either Cellular or Mobile Data.
- Tap Cellular Data.
- Tap the number you want to use cellular data.
If you turn on Allow Cellular Data Switching, then while you're on a voice call on your voice-only number, that number automatically switches to use voice and data.* This lets you use both voice and data while on the call.
If you turn off Allow Cellular Data Switching and you're active on a voice number that isn't your designated cellular-data number, then cellular data won't work while you're on the call.
To turn on Allow Cellular Data Switching, follow these steps:
- Go to Settings.
- Tap either Cellular or Mobile Data.
- Tap Cellular Data.
- Turn on Allow Cellular Data Switching.
* Your data line switches automatically for the duration of your call. This cellular-data switching will not work if you are currently using Data Roaming. Check with your carrier for availability and to find out if additional fees apply.
To change your cellular settings for each of your plans, follow these steps:
- Go to Settings.
- Tap either Cellular or Mobile Data.
- Tap the number you want to change.
- Tap each option and set it as you normally would.
