The most common fix for a travel eSIM with no connection is switching data roaming on for that line; it resolves more cases than every other remedy combined. eSIMs fail for a short, predictable list of reasons, and nearly all of them are settings, not faults.
That is worth internalising before you touch anything, because the instinctive fixes are the dangerous ones. Deleting and reinstalling, the reflex from a decade of restarting routers, is precisely the wrong move with an eSIM: many travel profiles are single install, and deletion can turn a two minute settings problem into a dead plan.
This guide is ordered as a decision tree, from most likely cause to least. Start at check one and work down; most travellers are back online before check three. If you have not installed the profile yet and are troubleshooting the installation itself, start instead with our installation and activation guide and come back here if the connection fails after install.
In this guide:
- Check one: is data roaming switched on
- Check two: is the eSIM set as your data line
- Check three: cycle aeroplane mode and restart
- Check four: select a network manually
- Check five: review the APN settings
- Check six: confirm the plan is active and has data left
- Why you should not delete and reinstall the eSIM
- When to contact support
- Symptoms and fixes at a glance
- Back online: your next step
Check one: is data roaming switched on
Travel eSIMs are issued by networks whose home country is usually not the one you are standing in, so your phone classifies the connection as roaming and blocks data until the roaming toggle says otherwise. With a prepaid plan the toggle carries no cost risk; it is a permission, not a meter.
On iPhone: Settings, Mobile Service (Cellular in the US), tap the travel line, then Data Roaming on. On Android: Settings, Network and internet (or Connections on Samsung), select the travel SIM, then Data roaming on. The toggle is per line, so make sure you are editing the travel eSIM and not your home SIM; roaming can stay safely off on the home line.
If data starts flowing, you are done. This single toggle closes the majority of cases.
Check two: is the eSIM set as your data line
The second most common failure: the eSIM is installed, enabled and roaming, but the phone is still routing data through your home SIM, which either has roaming disabled (no connection) or roaming enabled (an expensive surprise).
On iPhone: Settings, Mobile Service, Mobile Data, and select the travel line. While there, turn off Allow Mobile Data Switching so iOS cannot drift back to the home line. On Android: Settings, Network and internet, SIMs (or SIM manager on Samsung), and set Mobile data to the travel eSIM. Also confirm the travel line itself is toggled on; a line that is installed but switched off shows in the list yet does nothing.
Running two lines confuses more setups than any other factor; our dual SIM travel setup guide shows the exact combination of defaults that keeps calls on your home number and data on the travel plan.
Check three: cycle aeroplane mode and restart
Phones sometimes cling to a failed network registration. Aeroplane mode forces a clean re-registration: switch it on, count to twenty, switch it off, and give the phone a minute to negotiate. This clears a large share of the connects-then-drops and stuck-on-no-service cases, especially right after landing when the phone first meets the local networks.
If aeroplane mode does not do it, restart the phone fully. A reboot rebuilds the modem session from scratch and resolves oddities that toggles cannot reach. Between the two, this step fixes most of what checks one and two did not.
Check four: select a network manually
Travel eSIMs typically work through one or more partner networks in each country, and occasionally your phone camps on a network the plan cannot use, or refuses to pick one at all.
On iPhone: Settings, Mobile Service, tap the travel line, Network Selection, switch off Automatic, wait for the list, and try the available networks one by one, giving each a minute. On Android: in the travel SIM’s settings, choose Network operators, disable automatic selection and do the same. If your plan’s documentation names supported networks, start with those; if a manual choice connects, you can usually return to automatic afterwards and it will remember what worked.
This check earns its place in remote regions and border areas, where the strongest signal is not always a supported network.
Check five: review the APN settings
The APN (access point name) tells the phone which gateway carries your data. Most eSIM profiles configure it automatically during install, but a few need it set by hand, and some Android phones ignore the pushed value.
Find the APN under the travel line’s settings: on iPhone, Settings, Mobile Service, the travel line, then Mobile Data Network (this menu only appears when the profile allows manual APN); on Android, the travel SIM’s settings, then Access point names. Compare what is there against the APN printed in your plan’s installation email, correct it if it differs, save, and cycle aeroplane mode once more. Do not invent values: the correct APN comes from your provider’s documentation, nowhere else.
Check six: confirm the plan is active and has data left
If everything above is correct and data still will not flow, the problem may be the plan rather than the phone. Three states masquerade as faults: a plan that has not started yet, a plan whose validity window has already ended, and a plan whose data allowance is exhausted (some plans drop to zero rather than throttling).
Check the confirmation email for the activation policy: some plans start at purchase, others at install, others on first network connection. Then check remaining data through your provider’s plan page or the usage details from your confirmation email. An exhausted or expired prepaid plan is not revivable, but the fix is painless: prepaid plans from Viasimo are one off purchases delivered by email within minutes, so a fresh plan can be bought, installed and online faster than most support tickets get a first reply.
Why you should not delete and reinstall the eSIM
On any other technology, remove and reinstall is a safe reflex. On eSIMs it is the one move that can make things permanently worse: many travel profiles are single install, bound to the first device that downloaded them, and once deleted they are gone even though the plan behind them may still be running. A settings problem then becomes a lost plan.
The rule: never delete a travel eSIM profile mid trip without first confirming, in writing, that your provider can reissue it to your device. If support explicitly instructs a reinstall and confirms the profile will be reissued, follow their steps exactly. Otherwise, deletion is the last resort after every check above and a support conversation, not before.
When to contact support
Contact support when the checks are exhausted or when the symptom involves anything on the provider side: a QR code that will not scan or reports itself as already used, an install that fails partway, a plan that shows active but has passed every device check, or any situation where reinstalling looks like the only option left. Around the clock support via live chat and email means a landing at 3am is not a reason to wait.
Speed the conversation up by including: your phone model and OS version, the destination country, which checks from this guide you have completed, what the status bar shows (no service, signal without data, wrong network name), and your order or plan reference. That set usually turns a back and forth into a single reply.
One more possibility worth ruling out before writing in: if the eSIM never installed at all and the option was missing from Settings, the phone itself may be carrier locked or a regional variant without eSIM; two minutes with our device compatibility checker settles that.
Symptoms and fixes at a glance
| Symptom | Most likely cause | Fix |
|---|---|---|
| Signal bars but no internet | Data roaming off on travel line | Check one |
| No service on the travel line | Failed network registration | Checks three and four |
| Home SIM roaming charges appearing | Data still routed to home SIM | Check two |
| Connected but pages never load | Wrong or missing APN, or a stuck VPN | Check five; disable VPN |
| Worked for days, then stopped | Data exhausted or validity ended | Check six |
| QR code will not scan or says used | Provider side profile issue | Contact support; do not delete anything |
| No Add eSIM option in Settings | Locked phone or unsupported variant | Compatibility checker; carrier unlock |
Back online: your next step
Run the checks in order; roaming, data line and an aeroplane mode cycle resolve the overwhelming majority of failures within five minutes, and manual network selection catches most of the rest. Keep the profile installed no matter what, and bring in support the moment provider side symptoms appear.
The best troubleshooting is the kind you never do: install over reliable Wi-Fi before departure, preset the roaming and data line toggles at home, and test the setup the moment you land rather than the moment you need it. Do that once and this guide becomes something you read, not something you use.
