eSIM APN settings explained: when a travel eSIM needs one and how to enter it

What an APN does on a travel eSIM

An APN is the name of the gateway that connects a mobile network to the internet. When your phone opens a data connection, it sends this name to the network, and the network uses it to decide where your data goes and which account it belongs to. If the name is wrong or missing, the network accepts your phone but refuses the data session. That is why a bad APN typically looks like full signal bars with no internet.

On a travel eSIM, the APN normally belongs to the company that issued the eSIM profile, not to the local network you see on your screen. Most travel eSIMs work by roaming: your phone joins a partner network in the country you are visiting, and your data is passed back to the issuer's gateway. The APN points to that gateway. This is why the network name on your phone shows a local operator, while the APN in the settings often looks unrelated to it.

In most cases the APN arrives together with the eSIM profile, or the phone takes it from its built-in carrier settings. You only notice it when that automatic step does not happen.

Do you need to set an APN at all?

Usually not. Enter an APN only in one of these situations:

• Your provider tells you to. If the installation email, the app or the QR code page lists an APN, enter exactly that value once the eSIM is installed.
• You have signal but no internet. The travel line is connected to a network, mobile data and data roaming are on, but nothing loads, even after a restart.
• Data works, but the hotspot does not. Some providers need a separate APN entry, or an extra APN type, for sharing data.
• Data stopped after a system or carrier update. Updates can replace an APN you entered by hand with the default one.

This table helps you tell an APN problem from other faults:

Slow data is almost never an APN issue; our guide to slow eSIM internet abroad covers those causes.

Five checks before you touch the APN

Changing the APN is the right fix only when the basics are in order. Go through these first, in this order:

1. Turn the travel line on. In the SIM or mobile settings, the travel eSIM must be switched on.
2. Set it as the line for mobile data. On a phone with two lines, data only flows through the line you select for mobile data.
3. Switch on data roaming for the travel eSIM. Most travel eSIMs roam on partner networks, so without roaming they never start a data session. Roaming on the travel eSIM does not cost extra; keep it off for your home SIM.
4. Restart the phone, or switch airplane mode on and off. This forces a fresh connection.
5. Try another network. Switch off automatic network selection and pick a different partner network from the list.

If you still have signal but no internet, the APN is the next thing to check. Our checklist eSIM not working abroad? 10 fixes covers the other causes in more detail.

How to enter an APN on iPhone

On iPhone, APN settings are stored per line, so changing them for the travel eSIM does not affect your home SIM. The menu is called Mobile Service in some regions and Cellular in others.

1. Open Settings > Mobile Service (or Cellular) and tap the travel line in the list of SIMs.
2. Tap Mobile Data Network (or Cellular Data Network).
3. In the Mobile Data section, type the APN exactly as your provider gives it. Leave Username and Password empty unless the provider lists values for them.
4. If the instructions also mention the hotspot, enter the same APN, or the one they give for it, in the Personal Hotspot section.
5. Go back. iPhone saves the entry automatically. Then switch airplane mode on and off, or restart the phone.

To undo your changes, scroll to the bottom of the same screen and tap Reset Settings. The installation itself is covered in our guide How to install an eSIM on iPhone.

How to add an APN on Android

On Android the APN list is also kept per SIM, but the menu names differ by manufacturer:

1. Open the APN list of the travel SIM, not the one of your home SIM.
2. Tap Add or the + symbol.
3. Under Name, type any label, for example the provider's name. Under APN, type the value from your provider exactly.
4. Fill in other fields only if the instructions list them. The next section explains which ones matter.
5. Save through the three-dot menu, then go back and select the new entry so its circle is marked. An APN that is saved but not selected has no effect.
6. Switch airplane mode on and off, or restart the phone.

If the list is greyed out or there is no Add button, the eSIM's carrier settings lock the APN and only the provider can change it. To undo your changes, use Reset to default in the three-dot menu of the APN list. Installation steps for Samsung, Pixel and Xiaomi are in our guide How to install an eSIM on Android.

Which APN fields matter, and which to leave alone

An APN entry on Android has many fields, and iPhone shows a few of them. For a travel eSIM, almost all of them should stay as they are:

The most common mistake is not a missing field but an extra character: a space at the end, a full stop copied from an email, or a letter that autocorrect changed. Compare the value character by character with the provider's instructions.

Does the APN change when you change country or network?

For most travel eSIMs it does not. Because the data goes back to the issuer's gateway, the same APN works on every partner network and in every country the plan covers. That matters on regional plans: you do not need to change anything when you cross a border, and your phone may switch between several partner networks within one country without you noticing.

How many networks that can be is shown in this table of the networks used by Japan plans in our database:

There are exceptions. Some eSIMs use a local operator's own profile in certain countries, and some providers install a second profile for part of their coverage. Each profile then comes with its own APN, which is usually set automatically. If your provider's instructions list different APNs for different countries or profiles, follow that list.

Before you buy, you can see which networks each plan uses on our destination pages, for example eSIM plans for Japan.

Common APN mistakes and how to undo them

• Entering the APN on the home SIM. The travel APN only works with the travel eSIM. If you changed the home line by mistake, reset its APN settings as described above.
• Using an APN from a forum or another provider. An APN only works with the eSIM it belongs to. A value that worked for someone else's plan will not help yours.
• Saving but not selecting the entry on Android. Only the selected entry is in use.
• Collecting entries from experiments. Delete the entries you added and keep only the one from the provider.
• Not checking again after an update. A system or carrier settings update can restore the default APN. If data stops after an update, look at the APN first.

A wrong APN does not damage the eSIM and does not use up your data. It simply blocks the connection until the right value is in place. If the correct APN is set, the five checks above are done and there is still no data, contact the provider's support with the network name your phone shows and a screenshot of the APN screen. A problem on the provider's side, such as a plan that has not been activated, cannot be fixed on the phone.

After the trip there is nothing to change back on the travel eSIM. Switch the line off, set mobile data back to your home SIM and keep the eSIM installed if you may use it again. If you are still choosing a plan, compare eSIM plans by destination; our guide to sharing travel eSIM data as a hotspot covers the hotspot APN in more depth.