Compare eSIM plans for Guernsey

Guernsey is a Crown Dependency, which puts it outside both the United Kingdom and the European Union for roaming purposes. A UK plan stops working when you land, and a Europe bundle only reaches you if it names Guernsey outright. Sure and JT serve the Bailiwick, and the useful detail is that the smaller islands sit under the same country code: Alderney, Sark and Herm need no separate purchase. What they do need is a realistic expectation, because the network scales with the population, and on Sark that is a few hundred people.

• ●St Peter Port, Castle Cornet and the main island road network are reliable, with usable 4G. The south cliff path is the one place on Guernsey where coverage comes and goes, dropping in the sheltered valleys behind Moulin Huet Bay and Pleinmont and returning as soon as you are back on an exposed headland. Nothing on a day walk is far from a signal.
• ●Alderney has its own sites and a modest amount of capacity, enough for maps, messaging and calls. Herm, car-free and tiny, runs on a light footprint. Sark is the one to plan around: an island that has banned cars and streetlights is not a place to schedule a video meeting from, and that is more or less the point of going.
• ●The crossings between islands pass through fast tidal races where coverage is intermittent. Ferry schedules shift with tides and weather, so keep them offline rather than assuming you can look them up from the boat.

Sources: Internet Society Pulse: Guernsey, ITU DataHub: Guernsey, Ookla Speedtest Global Index, Visit Guernsey: official tourism board