Most of the smartphones launched on the market are presented as dual SIM, or capable of being able to manage two separate cards (and therefore numbers) simultaneously. Even the new iPhones are not an exception: even the latest Apple devices such as iPhone XS, Max and XR can easily manage two SIMs at the same time.
iPhone XS, Max and XR are dual SIMs after updating to 12.1
Although the door for the second SIM was logically already available on the devices, it is with the recent update 12.1 that the new iPhone users can definitely make use of this feature so important.
For dual SIM support, the new iPhone uses a traditional SIM for the primary number and an eSIM for the secondary account. If the operator of the second card supports eSIM technology, the additional number can be configured.
Also keep in mind that if the numbers are of the same operator, just insert the two cards and you can safely operate on both: only if the second slot is occupied by a different operator you have to intervene with the following settings.
How to set up the second SIM card
First, go to the Settings menu. From there, choose the Phone option. After that, choose Add phone plan and, if everything goes well, a QR scanner should activate. All relevant information will be added instantly and everything will be resolved immediately.
If you do not have a QR code, however, you will need to enter this information manually. Touch the Enter details manually button at the bottom of the display. All the necessary information here should be provided by your operator, if you are missing something (excluding the confirmation code, which is optional and may not be provided) you will need to contact the service directly to know all the data to be entered.
Once you have entered the correct details, you need to establish the connection and you will be able to take advantage of all the dual SIM capabilities on your iPhone.