Glossary
- eSIM
- An embedded SIM. It's a digital SIM that lives inside the phone itself, activated by scanning a QR code or installing a profile. No plastic card to lose.
- Data-only plan
- A plan that gives you mobile data and nothing else. No local phone number to receive calls or texts on. Most travel eSIMs are built this way.
- Validity
- How long the plan keeps working after activation, measured in days. Whatever data you haven't used by then disappears with it.
- Price per GB
- The plan's total price divided by its data allowance. It's the cleanest number for putting fixed-data plans head to head, since plan sizes vary so much.
- Fair-use cap
- A daily speed throttle hidden inside most 'unlimited' plans. You run at full speed up to a set amount of data each day, after that, the speed drops, sometimes a lot.
- Carrier / network
- The actual local mobile operator your eSIM hops onto when you land (KDDI in Japan, say, or Orange in France). Plans that can use more than one carrier give you somewhere to fall back when the first network gets patchy.
- Top-up
- Buying more data for an eSIM you already have, instead of starting a fresh plan from scratch.
- Regional plan
- A single eSIM that covers a whole batch of countries in one region. Handy when you're crossing borders, since you don't have to swap plans every time you change country.