How to set up and use Dual SIM — Apple Support

With iPhone XS, XS Max, and XR, you can add a second phone line and use both numbers on a single iPhone. This is handy if you need a separate business number, or if you’re traveling out of the country and want to use a local plan while you’re away. Here’s how it works. To activate dual SIM, you have to buy a plan from a carrier in the form an eSIM. Setup may vary depending on your carrier. Some may require you to download their app to purchase and activate the plan, while others will provide a QR code. if you’re adding an eSIM using a QR code, open Settings, tap Cellular, then tap Add Cellular Plan. ♪ Music playing ♪ From here, use your iPhone camera to scan the QR code.

When your iPhone detects the QR code, you’ll see this screen appear. Tap Add Cellular Plan, and then label your phone numbers so you know which is which. Tap Primary to label your original phone number. You can pick a suggested label like Personal, Business, or Travel, or create your own custom label. We’ll change this one to Personal. Now tap Secondary to label the new number you just added. We’ll use this one for travel. ♪ When you’re done, tap Continue. Next, select a default number. This is the number you’ll use for iMessage and to call or send messages to contacts that are not in your address book. Your other number will still be available for calls and SMS. Then tap Done. On the Home screen, you’ll see two cell signal bars that pair with each of your numbers. Swipe down from the top right to open Control Center, where you can get a better look at the cell signal strength for each number.

Need to make a phone call? Open the Phone app as usual and select a contact. If you haven’t assigned a preferred number to the person you’re calling, you’ll use the number from your last communication with this person to start new phone calls and messages. To assign a preferred number, tap Last Used under the contact’s name, then select a number to always use. ♪ If you dial an unsaved number like a new pizza place, your iPhone will select your default number for the call. You can change the number you’re using by tapping this gray bar with your default number right above the number pad and then selecting the line you’d like to use. When you receive a phone call, you ‘ll see an icon under the contact’s name or number that tells you which number the call is for.

Looks like Uncle Dave is calling my personal number. I’ll call him back later. Sorry, Uncle Dave. Let’s send him a follow-up message. In Messages, your default number will be used automatically when you start a new message. To change this, tap the green or blue bar with your default number and select which number you’d like to use. You can only change the number when starting a new message. It can’t be changed in an existing message. Then type out your message and tap Send. You can tweak the settings for each number at any time.

Just open Settings and tap Cellular. And that’s how you use two phone numbers on just one iPhone. 

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