You have landed, switched off airplane mode, and nothing happens. No bars, no data, no maps to find your taxi. It is one of the most stressful moments of travel, but in most cases the fix takes less than five minutes and does not require finding Wi-Fi or calling anyone. Work through these five steps in order.
Step 1: Turn airplane mode off, then back on
This sounds almost too simple, but it forces your phone to search for a network again, and clears many temporary connection glitches. Toggle airplane mode on for ten seconds, then off, and give your phone thirty seconds to search for a signal before assuming it is a bigger problem.
Step 2: Check data roaming is switched on for your eSIM
This is the single most common reason a correctly installed eSIM shows no data on arrival. Installing an eSIM and activating data roaming for that specific line are two separate steps, and it is easy to complete the first without the second.
- On iPhone: Settings, Cellular, tap your travel eSIM line, then make sure Data Roaming is switched on.
- On Android: Settings, Network & Internet, SIMs, tap your travel eSIM line, then make sure Roaming is switched on. Apple’s eSIM support page and Google’s guide to setting up a new eSIM both cover this step in more detail for their respective devices.
Step 3: Confirm the eSIM is set as your active data line
If you have two SIMs (your home SIM and your travel eSIM) installed, your phone needs to know which one to use for data. Check under your SIM or Cellular settings that “Mobile Data” or “Data SIM” is set to your travel eSIM, not your home SIM, which will not have local coverage abroad.
Step 4: Manually select the network
Occasionally a phone gets stuck trying to connect to the wrong local network. Go into your Network Selection settings (usually under Cellular or Mobile Network settings), switch from “Automatic” to manual, and choose a listed network yourself. Switching back to Automatic afterwards usually resolves the issue, as it forces the phone to re-scan.
Step 5: Restart your phone
If the first four steps have not worked, a full restart clears almost any remaining network configuration issue. This is a genuine last resort that fixes the majority of stubborn cases, since it forces every radio and network setting to reinitialise from scratch.
Still no luck?
Check your OneSim dashboard to confirm your eSIM shows as active and has remaining data. If everything looks correct there but you still have no signal, it is worth double-checking your device is genuinely supported using our device compatibility checker, since a locked or unsupported device can sometimes install an eSIM profile without being able to actually use it.
How to avoid this next time
Install and fully test your eSIM before you fly, ideally over Wi-Fi at home, by briefly switching your active data line to the eSIM and confirming data roaming is on. Our guides on installing an eSIM on iPhone and Android walk through every setting so nothing is missed before departure.
Key takeaways
- Toggling airplane mode is a quick first fix that solves many temporary glitches.
- Data roaming must be switched on separately for your eSIM line, even after installation.
- Make sure your eSIM, not your home SIM, is set as the active data line.
- A restart resolves most remaining issues if the settings above all look correct.
FAQ
Why does my eSIM show as installed but still have no signal?
Most often this means data roaming is not switched on for that specific line, or the eSIM is not set as your active data SIM. Both are quick fixes in your settings.
Could my plan have already run out of data?
Check your dashboard, which shows your remaining data allowance and lets you top up instantly if needed.
Should I reinstall the eSIM if it is not working?
Try the five steps above first, since reinstalling is usually unnecessary and OneSim QR codes are typically single-use per device.
Want to avoid this altogether next trip? Read our step-by-step guides to installing an eSIM on iPhone or Android before you fly.