Codes sent by text arrive on your home number, not on the eSIM — so keep that line switched on. Codes from an app arrive over data and work on the eSIM as normal
This catches people out at the worst moment, usually in front of a payment screen. A data-only eSIM has no number, so nothing can be texted to it.
Which Codes Come Which Way
| Type | Arrives Via | Works Abroad? |
|---|---|---|
| SMS code from a bank | Your home number | Yes, if the home line is on |
| Banking app push approval | Data | Yes, over the eSIM |
| Authenticator app code | Nothing — generated offline | Yes, always |
| eMail code | Data | Yes, over the eSIM |
| Automated voice call code | Your home number | Yes, if the home line is on |
Before You Fly
- Keep the home SIM in the phone and switched on, with data roaming off
- Move important accounts to an authenticator app, which needs no signal at all
- Check your bank's app works with push approval rather than SMS
- Add a backup contact method to accounts you cannot afford to be locked out of
If you are travelling without your home SIM — an eSIM-only phone, or a second device — plan the codes before you leave. Being locked out of a bank in another country with no way to receive the code is a genuinely bad afternoon.
Receiving a text abroad is free in most countries. Keeping the home line on costs nothing as long as its data roaming is off
