Four bars of signal and nothing loads. No maps, no WhatsApp, no boarding pass refreshing in the airline app. It's one of the most disorienting moments in travel because the phone looks fine. The signal icon says you're connected. The internet just isn't there.
Good news first: this is almost always fixable in under five minutes, and almost never means your eSIM is broken or your money is gone. Full signal with no data is a specific, well-understood fault, and it comes down to one of three things nearly every time: data roaming being switched off, your phone using the wrong SIM for data, or an APN setting that didn't configure itself properly. Work through those three in order and you'll usually be back online before your coffee's finished.
Why signal bars don't mean you have data
Signal bars measure something narrower than people assume. They tell you your phone has found a nearby tower and can talk to it, nothing more. Voice, SMS, and data are handled as separate layers on top of that connection, and a phone can quite happily register "full signal" while the data layer is switched off, misdirected, or blocked by a setting you don't normally think about.
This is why rebooting your phone often doesn't fix it. A restart re-establishes the signal connection, which was never the problem, so you end up with the exact same four bars and the exact same blank browser. The fix lives in settings, not in power cycling.
Check data roaming first (it's the most common cause by far)
Every travel eSIM, including EscapeSIM eSIMs, works by connecting to a local network partner abroad rather than your home carrier. Your phone treats that connection as "roaming" even though it's the only network you actually want to use. If Data Roaming is switched off for that eSIM line, your phone will register signal and sit there doing nothing, because it's deliberately refusing to pass data over a roaming connection.
On an iPhone, go to Settings, tap your travel eSIM under Mobile Data or Cellular, and make sure Data Roaming is turned on for that specific line, not just the general toggle. On Android, the setting usually lives under Network & Internet, then SIMs, then the eSIM you're using, with Roaming listed as its own switch. It sounds almost too simple to be the fix, but it resolves the issue for most travellers who hit this wall, especially anyone who's used their home SIM for years and never had to think about roaming before.
If you want the full walkthrough with screenshots for both operating systems, the Data Roaming Setup guide covers it step by step.
Make sure the eSIM is actually set as your data line
If your phone is running dual SIM, meaning your home SIM is still installed alongside the travel eSIM, this is the second most likely culprit. Phones default to using whichever line was primary before you left, and that's often the home SIM, not the travel eSIM. Your phone will show signal from the travel eSIM (it's sitting there, active) while all your data requests still route through the home line, which may have no roaming data at all, or be silently blocking it to avoid charges.
You want both lines active for calls and texts if you're keeping your home number alive for OTP codes or family contact, but mobile data specifically needs to point at the travel eSIM. On iPhone, this is Settings, Cellular, Cellular Data, then select the travel eSIM. On Android it's the same Network & Internet menu, with a specific "Mobile data" selector that lets you pick which SIM handles data while leaving calls on the other.
This trips up a particular type of traveller a lot: someone doing a two-week trip across several countries, keeping their home SIM for banking apps and two-factor codes, assuming the phone will "just know" which line to use for data. It won't. You have to tell it. If you're not sure your eSIM is even showing up correctly in this menu, eSIM Not Connecting To Data walks through what it should look like.
Check or reset the APN settings
The APN, or Access Point Name, is the technical address your phone uses to find its way onto a network's data service. Most eSIMs configure this automatically the moment they activate, but occasionally it doesn't populate correctly, especially if you installed the eSIM days before flying and then had a software update land in between.
You generally shouldn't need to touch this manually. If roaming is on and the data line is set correctly and you're still stuck, the next step is to toggle Airplane Mode on for about 15-20 seconds, then off again. This forces the phone to drop its current network registration and rebuild the connection from scratch, including re-fetching the correct APN profile. It's a genuinely useful first move before you go digging into menus, because it fixes a surprising number of cases on its own.
If that doesn't shift it, a full network settings reset (not a factory reset, just the network one) clears out any stale configuration. On iPhone it's Settings, General, Transfer or Reset iPhone, Reset, Reset Network Settings. On Android it's typically under System, Reset Options. Know going in that this will drop saved WiFi passwords and Bluetooth pairings too, so it's worth doing once you've ruled out the simpler fixes rather than as your first move.
One thing not to do: don't delete the eSIM
When nothing seems to work, the instinct is to remove the eSIM profile and start again. Resist it. Many eSIM QR codes and activation codes are single-use, which means deleting the profile can mean losing access to that data plan entirely, with no way to reinstall it. Troubleshoot the settings first. Deleting and reinstalling should be a genuine last resort, not a first reaction to frustration.
If your eSIM shows "No Service" rather than full signal, that's a different and separate problem, usually related to network selection or an installation issue rather than anything in this guide. The No Signal No Service page deals with that specific scenario.
What to do if you're still stuck
Try manually selecting a network. Automatic network selection usually picks the right local partner, but occasionally it latches onto a network your eSIM isn't provisioned to use. Going into Settings and manually choosing a different available carrier from the list can resolve this instantly, particularly in border regions or smaller towns where several networks overlap.
Think about where you actually are, too. A remote worker running a hotspot from a rural guesthouse, or a family on a road trip through national parks, will hit genuine coverage gaps that have nothing to do with settings. If you've gone through roaming, data line selection, airplane mode, and a network reset and you're still blank, it may simply be a weak-coverage pocket rather than a configuration fault. Moving a few hundred metres, or waiting until you're back in a town centre, sometimes solves it faster than any setting does.
It's also worth building a few habits before you fly next time that reduce how often this happens at all, like checking your eSIM is active and correctly set before you leave home rather than at airport WiFi with ten minutes until boarding. For broader advice on managing data sensibly once you're connected, How To Conserve Mobile Data While Travelling Internationally is a useful companion read. And if you're still deciding on a plan for an upcoming trip, browsing the current eSIM plans for destinations like Greece or Japan will show you what's actually available before you go, rather than guessing.
よくある質問
Why does my eSIM have signal but no internet?
Do I need to turn on data roaming for a travel eSIM?
Should I delete and reinstall my eSIM if it's not working?
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