We’ve all been there. You buy an international eSIM for your trip and are excited to stay connected, it doesn’t work. No signal, no data, endless errors.

Why? The truth is, most eSIM issues aren’t random. They’re fixable. We’ve helped thousands troubleshoot these problems, and today, we’ll share the top reasons your international eSIM fails abroad.

From compatibility headaches to hidden network rules, we’ll break down exactly what’s going wrong. No tech jargon, no fluff. Let’s fix your eSIM struggles for good.

Your Phone Isn’t eSIM-Compatible

Many phones sold in the US or Europe still don’t support eSIMs. For example, older iPhone models (before XS) or budget Android devices won’t work. Check your phone’s settings: Go to “Cellular” > “Add Cellular Plan.”

If you don’t see an “Add eSIM” option, your phone can’t use an international eSIM. Always verify compatibility before buying. We’ve seen travelers waste $50 on eSIMs for unsupported devices. Don’t be that person.

You Bought the Wrong International eSIM Plan

Not all international eSIMs work everywhere. Say you’re planning to travel to Europe, so you buy a “Zone EU” plan, but you are still in your home country, USA for example. If you load your eSIM in your home country and then try to use your eSIM for data, the data plan you purchased (again, for EU) will not work. You will need to either put funds on the eSIM to use per MB data or purchase a small package that covers your home country so you can test.

Always check the fine print: Does it cover all the countries in which you are going to use the international eSIM? For example, a “30-country” plan might exclude popular spots like Croatia. Match the plan to your exact itinerary.

Are there speed caps? Reputable international eSIM providers like OneSimCard will list the data speeds for each country prominently. OneSimCard lists this on our Rates Page. We also list the networks we use in each country at the bottom of that page in the “View Roaming Network Details” section.

Your APN Settings Are Blocking Data

APN settings tell your phone how to connect to the internet. If these are wrong, even a working international eSIM fails. Go to Settings > Cellular > eSIM > APN. Often, the APN name auto-fills, but we’ve seen cases where it stays blank, or is set to the wrong APN.

Manually enter the APN your eSIM provider lists. For OneSimCard, you can find our APN settings for our SIM cards in our FAQs. Still stuck? Reset network settings. This fixes 80% of “no service” errors.

Data Roaming Isn’t Enabled

Another very common mistake travelers make when trying to use international eSIM cards is they don’t enable data roaming on their device. Don’t worry, though, because the fix is super simple!

We have created video tutorials demonstrating how to enable data roaming on iPhone and Android devices:

For iPhone devices, the video can be found HERE.

For Android devices, the video can be found HERE.

Your eSIM Activation Glitched Mid-Trip

International eSIMs sometimes deactivate if you switch networks too often. Imagine you’re on a train from France to Germany—your eSIM might “lock” to one tower and refuse to connect elsewhere.

Restart your phone. If that fails, delete the eSIM profile and reinstall it. However, there may be restrictions on how many times you can re-install an eSIM profile, so keep this as an “if all else fails” step. Pro tip: Activate your eSIM before leaving home (see note above about plans and where they work, though). Airport Wi-Fi is spotty, making activation risky.

Activation Nightmares in Foreign Airports

 

Ever tried activating an eSIM while jet-lagged? It’s a recipe for disaster. We’ve seen countless travelers stuck at airport info desks, frantically trying to get online.

The problem? Activation often requires a stable internet connection—which you don’t have yet! Here’s a quick fix: Download your eSIM before leaving home.

Then, activate it while still connected to your home network or airport Wi-Fi. Can’t do that? Look for free Wi-Fi spots in the arrival area.

Many airports now offer 15-30 minutes of free internet, perfect for a quick eSIM setup. Remember, patience is key.

Final Thoughts

International eSIMs should simplify travel, not stress you out. Most failures happen because we skip basics—checking phone compatibility, reading plan details, or testing APN settings.

Follow our fixes, and you’ll avoid 90% of issues. Still stuck? Contact our best-in-class USA based support immediately. Remember, even experts can face glitches.

The key is knowing how to pivot. Next trip, your international eSIM won’t suck. It’ll be your best travel buddy.