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How a travel eSIM works

An eSIM is a SIM card built into your phone. Instead of collecting a piece of plastic, you install a data plan by scanning a code — which means you can be connected before you land.

Installing an eSIM on iPhone

  1. Buy a plan. Pick your destination in Num, choose how much data you need, and pay with Apple Pay.
  2. Get your QR code. The app issues it as soon as payment completes — usually within seconds.
  3. Add the eSIM. On your iPhone: Settings → Cellular → Add eSIM → Use QR Code, then scan the code. You can also save the code to Photos and choose it from there.
  4. Turn on data roaming. Select the Num line and enable data roaming, then set it as your cellular data line. This is the step people miss.

Do this on wi-fi before you fly. Installing an eSIM needs an internet connection, which is exactly what you don't have when you land.

Keeping your own number

Your normal SIM stays active. Calls and texts arrive on your usual number while data runs over the travel plan. To avoid a roaming bill, turn data roaming off for your home line and on for the Num line.

Why an eSIM instead of roaming?

Roaming bills your home rate, often per day, and is capped or throttled in ways that are hard to predict. A travel eSIM is bought up front at a known price, so there is no bill waiting when you get home. Compare the two in detail →

Common questions

Do I need to remove my normal SIM?

No. An eSIM is a second line stored digitally on the phone. Your existing SIM stays in place and keeps your number active for calls and texts.

Can I install the eSIM before I travel?

Yes, and it is the recommended approach — install while you have wi-fi at home. Most plans only start counting down when the eSIM first connects to a network in the destination.

Can I move an eSIM to another phone?

Generally no. An eSIM profile is normally tied to the device it was installed on, so install it on the phone you are travelling with.

What happens if I delete the eSIM?

An activation QR can usually only be installed once, so deleting a profile may mean it cannot be reinstalled. Contact support before removing an eSIM you still need.