iPhone has no mobile data abroad

Abroad, an iPhone with a home plan uses another carrier's network. Data then needs Data Roaming, a plan that allows roaming, and the right line for cellular data.

Fix this with your agentCopies a prompt for Claude Code, Codex or any agent that can use Terminal.

My Mac has this problem: iPhone has no mobile data abroad. Read https://kilobat.app/guides/iphone-no-data-abroad.md and work through it with me. Install the Kilobat CLI if it’s missing: brew install seifip/kilobat/kilobat. Run the guide’s Terminal and kilobat checks yourself and tell me what you find. List the steps only I can do. Ask before you change any setting.

Applies to: Current iOS versions. Connectivity Assist replaces Wi-Fi Assist in the latest iOS versions.Checked: 7 November 2026

Symptoms

  • The iPhone shows signal bars abroad, but apps do not load over cellular data.
  • The status bar shows No Service or Searching.
  • Data works on hotel Wi-Fi, but not on the street.
  • The Mac on the iPhone hotspot has no internet abroad.

Likely causes

  • Data Roaming is off. Apple says that Data Roaming permits internet access in a region that your carrier's network does not cover.
  • The plan does not include roaming. Apple says to check with your carrier about roaming on your plan, or about travel passes.
  • The wrong line for cellular data. With two lines, iPhone uses the line chosen under Cellular Data. Personal Hotspot uses the same line.
  • The carrier account or the device is blocked. Apple says to ask the carrier whether the account is active and the device is not barred.
  • Local registration rules. Apple says that some governments require IMEI registration for an iPhone bought in another country or region.
  • Weak Wi-Fi with no fallback. Apple says that Connectivity Assist is not used during international roaming. Weak Wi-Fi does not move to cellular.

How to check

  1. Open Settings > Cellular. Make sure that Cellular Data is on.

  2. With one line, tap Cellular Data Options. Look at Data Roaming.

  3. With two lines, tap the line that you use abroad. Then tap Cellular Data Options and look at Data Roaming.

  4. Tap Cellular Data. Make sure that it uses the line that has the roaming plan.

  5. Scroll down to the list of apps. Make sure that cellular data is on for the apps that you need.

  6. In the carrier's app or account, make sure that roaming or a travel pass is active for this country.

How to fix it

  1. Turn on Data Roaming for the line that you use abroad. Roaming charges can apply.

  2. Turn on Airplane Mode for at least 15 seconds. Then turn it off.

  3. Restart the iPhone.

  4. Install a carrier settings update in Settings > General > About, if one appears.

  5. Update iOS to the latest version.

  6. If the carrier names a partner network, choose it by hand. Then turn on automatic selection again later.

  7. Ask the carrier whether the account is active and set up for roaming.

  8. If roaming costs too much, add a local or travel eSIM. See Travel eSIM stuck on Activating or has no data abroad.

With Kilobat

  1. Kilobat runs on the Mac. It cannot see the iPhone's lines or its roaming settings.

  2. When the Mac uses the iPhone hotspot abroad, Kilobat shows which apps use the data. See See which app uses data on a hotspot.

  3. Set a budget for the roaming data. With Pro and the network filter, new connections stop at the limit.

    kilobat limit 1

  4. For prepaid data, add a data pack. It shows the data left and the day it runs out.

    kilobat pack add 5 7 --name "Roaming pass"

  5. With Pro and the network filter, Kilobat switches to Essentials on metered networks. Only the apps you allow can connect.

Questions

Data Roaming is on, but there is still no data. What now?

Make sure that the plan includes roaming in this country. Then try Airplane Mode, a restart and a carrier settings update.

Should I choose a network by hand?

Only if the carrier tells you. Vodafone says that a phone set to one network loses service when that network is out of reach.

Does Low Data Mode help when I roam?

Apple says that Low Data Mode pauses automatic updates and background tasks when iPhone is not on Wi-Fi.

Why does iPhone stay on bad hotel Wi-Fi?

Apple says that Connectivity Assist is not used while iPhone roams internationally. Turn off Wi-Fi to use cellular data.

Sources

Checked on 7 November 2026.