Vodafone Travel

Vodafone Travel is the official travel eSIM service from one of the UK's "big three" carriers, so you're getting the network operator's own offering rather than a reseller. Plans are data-only and designed specifically for tourists, with transparent pricing and no hidden charges. They also bundle regional packages covering parts of Europe, which suits travelers crossing the Channel from the UK.

This appeals most to anyone who values the credibility of buying directly from the carrier. Compared to third-party marketplaces, you get the carrier's customer service guarantee and their roaming reciprocals with partner networks across Europe.