What You'll Need Before You Start
You need three things: an eSIM-compatible iPhone 15 (all models support eSIM), a stable WiFi connection, and the QR code or activation details from your eSIM provider. We recommend aloSIM for travel eSIMs because they email everything you need in one clear message. Have your daughter's iPhone nearby and make sure it's charged to at least 50%. You do NOT need to remove the existing physical SIM — iPhone 15 can hold multiple cellular plans at once.
Step 1: Open Settings and Navigate to Cellular
On the iPhone 15, open the Settings app (the gray gear icon). Scroll down and tap 'Cellular' — it's about halfway down the list. You will see your current cellular plan listed here. Don't worry, you're not replacing it. Tap 'Add eSIM' or 'Set Up Cellular Service' depending on your iOS version. Apple may also label this as 'Add Cellular Plan.' All three lead to the same place.
Step 2: Scan the QR Code
Your eSIM provider (like aloSIM) emails you a QR code after purchase. Hold that email open on another device — a laptop, your own phone, or even printed on paper. The iPhone 15 camera will automatically detect the QR code when you point it at the screen. If the camera doesn't trigger automatically, tap 'Enter Details Manually' and type in the SM-DP+ Address and Activation Code exactly as shown in the email. Double-check every character — one wrong letter breaks the setup.
Step 3: Label Your Plans
After scanning, iPhone 15 asks you to label the new plan. We recommend 'Travel' or 'Italy' — something descriptive. This label appears in Control Center when you toggle between data sources. Your home carrier stays labeled as 'Primary' or whatever name you gave it. This dual-label system is what makes eSIM so powerful: your daughter keeps her US number for iMessage and calls while using the Italian data plan for everything else.
Step 4: Choose Which Plan Uses Data
iPhone 15 will ask which plan should be your default for data, calls, and iMessage. For travel: set the eSIM as the data plan, keep your home SIM as the call/iMessage plan. This means your daughter's phone number stays the same for texts from home, but all internet traffic (maps, Instagram, web browsing) flows through the affordable local eSIM data. Go back to Settings > Cellular > Cellular Data and confirm your eSIM is selected as the active data plan.
Step 5: Enable Data Roaming on the eSIM Only
This is the single most important step. In Settings > Cellular > [Your eSIM label] > turn ON 'Data Roaming.' This allows the eSIM to connect to Italian cell towers. Then, critically, go to your home carrier plan and turn OFF 'Data Roaming.' If you leave both on, your home carrier may charge $15 per day for international roaming even though the eSIM is active. The iPhone 15 will prioritize the eSIM for data, but carriers sometimes bill based on the roaming toggle alone.
Step 6: Test Before You Fly
Don't wait until landing in Rome to discover something went wrong. After setup, the eSIM profile appears in Settings > Cellular even though it has no signal yet (that's normal — it only activates in the destination country). But you can verify the profile is installed correctly. Some eSIM providers let you test with a small amount of data before departure. If aloSIM offers this, run a quick speed test on WiFi first, then briefly toggle off WiFi to confirm the eSIM icon appears in the status bar. You won't get real data at home, but you will see the signal indicator confirm the profile is recognized by the phone.
What to Do When You Land
Upon arrival in Italy, turn off airplane mode. Within 30–60 seconds, the iPhone 15 should connect to a local network — you'll see 'TIM,' 'Vodafone IT,' or 'Wind' appear in the status bar instead of 'Verizon' or 'AT&T.' Open Safari and load a webpage. If it works, you're done. If not, go to Settings > Cellular > [eSIM label] > Network Selection and manually choose a carrier. One of them will connect. This manual selection trick solves 90% of landing-day issues.
Troubleshooting Common Problems
If the QR scan fails, screenshot the QR code from the email and scan the screenshot instead — sometimes email clients compress images. If the eSIM won't activate, restart the iPhone 15 and try again. If data works but iMessage shows 'Waiting for activation,' toggle iMessage off and back on in Settings > Messages. If your daughter can't receive texts from her US friends, make sure her home SIM is still active for SMS — go to Settings > Messages > Send & Receive and confirm her US number is checked. The most common mistake parents make: turning off the home SIM entirely. Don't do that. Keep both active, just route data through the eSIM.