Keep your primary SIM while using travel data
Use dual-SIM controls to preserve your normal number while the travel eSIM handles mobile data.
Separate calls from data
A compatible phone can often keep two lines enabled. The primary line can remain available for its normal number while the travel eSIM is chosen for cellular data. Whether calls or messages on the primary line create carrier charges depends on that carrier and is outside the travel data plan.
Review three settings
- Default voice line: choose the number you intend to call from.
- Mobile data line: choose the travel eSIM.
- Data switching: turn it off if you do not want the phone to fall back to the primary line.
Check roaming per line
Roaming controls can be separate for each SIM. Follow the travel plan instructions for the eSIM and review the primary carrier settings before departure. A screenshot of the intended setup can make later troubleshooting much easier.