Yes, eSIM works internationally, and it's probably the easiest way to get online abroad if you're travelling for a week or two. The technology itself crosses borders without issue—the question is whether your phone supports it and whether you've bought a data plan that covers the countries you're visiting.
How international eSIM actually works
An eSIM is a digital SIM already built into your phone. When you buy an international data plan, you download a profile (usually by scanning a QR code or through an app) that connects you to mobile networks in whichever countries your plan covers. You can switch between your home number and your travel eSIM without swapping anything physical, which is why it's caught on with tourists who want data abroad without the airport kiosk scramble.
The important bit: your phone needs to be eSIM-compatible (most iPhones from XS onwards and many recent Androids are) and it must be unlocked—meaning not tied to a single carrier. If you bought your phone outright or finished paying off a contract, you're likely fine. If you're unsure, check your settings or ask your UK provider before you leave.
Not all eSIM plans cover every country. Some are single-country (cheaper if you're only visiting France, say), others cover whole regions (Europe, Asia, North America), and a few cover dozens of countries worldwide. For a short holiday, you want a plan that matches your itinerary without paying for coverage you won't use. rentnconnect offers both: eSIM plans you set up in the rentnconnect app (iOS and Android), starting from as little as one day, and mobile hotspot rental if you'd rather not fiddle with phone settings or need to connect multiple devices at once. Both are pay-as-you-go with no subscription, which makes sense for city breaks and short trips where you just need data for the duration.
What to check before you rely on eSIM abroad
First, confirm your phone is unlocked and eSIM-capable—this takes two minutes in your settings and saves a lot of stress at the airport. Second, buy your plan before you fly. You can download the eSIM profile whilst you're still on home WiFi, then activate it when you land. Some providers let you install the profile weeks in advance, which is handy if you're the plan-ahead type.
Third, understand what you're actually buying. Data-only eSIM plans give you mobile internet but not a local phone number for voice calls (though you can still use WhatsApp, FaceTime, Signal, and anything else that runs over data). If you need to call a restaurant or hotel, you'll either use your UK number on roaming (check what your provider charges) or a VoIP app. For most tourists, data is the only thing that matters—you're navigating with Maps, messaging friends, posting photos, not ringing up strangers.
Finally, check whether the plan lets you top up if you run out. Short trips are unpredictable—you might stream more than expected or tether your laptop from a café. With rentnconnect, you top up your eSIM directly in the app if you need more data, without buying a whole new plan. And if you're travelling with family or friends who don't have eSIM phones, or you'd rather not configure everyone's device separately, the mobile hotspot rental option means one small device keeps everyone connected. You pick it up, you return it, and you're done—no long contract, no subscription, just data for as long as you need it.