Your SMARTY SIM will not work abroad unless you make a one-off change to your phone settings. We’ve created a step-by-step guide to easily set up your phone to work for roaming. 🌍
Note: No need to change the settings back when you return to the UK.
If you're old school, we've also listed the written steps below:
How to set up your APN on iPhone (iOS 26)
Go to Settings.
Tap Mobile Data.
If you have more than one SIM or an eSIM, tap the plan you want to update (for example, your SMARTY SIM).
Tap Mobile Data Options.
Tap Mobile Data Network.
Under both Mobile Data and MMS, enter the following: mob.asm.net
Once entered, go back to save your changes.
Restart your iPhone to make sure the settings take effect.
Also check:
Go to Settings > Mobile Data > Mobile Data Options and make sure Data Roaming is switched on (especially if you’re using your phone abroad).
That’s the only thing you have to change. If there’s any information in other fields, you can leave it as it is.
It should look like this:
Still need a helping hand?, you can check out more here.