How do I make my iPhone choose a particular SIM card? I've called a contact today that has a setting 'Last used' in choosing what number to use, but iPhone called her using the other number. I've initiated the call from MacOS
MacBook
Hello sirj,
Welcome to Apple Support Communities!
I understand from your question that you have questions about the dual SIM capability. I can certainly help you with this!
This article will be a good resource for you. It will walk you through the necessary steps to resolve the question.
"Change your cellular data number
One number at a time can use cellular data. To change which number uses cellular data, follow these steps:
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:
* 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."
I hope this is able to resolve your issue. If you have any more questions or this does not resolve your issue, please reach back out on the thread!
Cheers.
Thank you for taking the time to answer, but it is a different question. Let me explain the scenario.
I'm working on a MacBook. I want to call someone. My AirPods are connected to a Mac. I open Contacts and click a phone icon next to a contacts cell number. MacOS initiates a call, I see 'Calling Contact using iPhone'.
The problem is that in this scenario this call ignores my iPhone's settings on what SIM card/phone number to use to call this contact. There is also no dialog on a Mac that allows me to choose which sim is going to be used.
sirj,
Thank you for the additional information regarding your device.
This is due to the face that the Mac does not have dual SIM functionality. Because this is the case, the Mac uses the phone's default way of choosing which SIM card to use. I would refer to the same article on how to set this default behavior.
"Set your default number
Choose a number to use when you call or send a message to someone who isn't in your Contacts app. With iOS 13, choose which cellular plans you want to use for iMessage and FaceTime. With iOS 13, you can choose either or both numbers.
On this screen, choose a number to be your default, or you can choose which number is to be used only for cellular data. Your other number will be your default. If you want your iPhone to use cellular data from both plans, depending on coverage and availability, turn on Allow Cellular Data Switching."
Cheers.
I'd say it is a bug and I hope it has been reported as one.
My default phone/sim for the contact I'm calling is set to #1
My default phone/sim for all unknown/not set contacts is set to #2
Call that is initiated from Mac is placed using phone/sim #2 ignoring my 'per-contact' setting in the phone. Meaning Mac forces the phone to use default sim.
I do see that there is no dual-sim support, but this behaviour has put me into a very uncomfortable situation.
Take care
Choosing a SIM for a call from MacOS
