A restriction that stops a phone from using other carriers' SIMs. A locked phone may not accept a travel eSIM.
Some phones are sold by a carrier with a lock that limits them to that carrier's network. A locked phone may refuse a travel eSIM even though the hardware supports it.
Phones bought unlocked, or ones where the carrier has removed the lock, work with any eSIM provider.
What to check
- Ask your carrier whether the phone is unlocked before you travel
- Check the lock status well before the flight