Why the bill grows abroad
Roaming charges do not come from the local network, they come from your home carrier's daily fee or per megabyte rate. The fix is to stop your usual SIM from using mobile data while you travel.
Before you leave
- Install the eSIM and switch it on while you still have Wi-Fi
- Set the eSIM as the line for mobile data
- Switch data roaming off for your usual SIM and on for the eSIM
On arrival
Your usual SIM can stay in the phone for calls and verification codes from your bank or airline. Calls you make on that line may still carry roaming rates, so keep them short or use messaging apps over the eSIM data connection.
If you need a local number
A data only eSIM keeps your own number active for incoming texts. If you also want a local number to call from, buy a local prepaid SIM at the airport and keep the eSIM for data.
Compare the daily rate
Most carriers publish a daily roaming fee. Put that next to the price of a plan for the same trip and the saving is usually clear.