Regional vs global eSIM: which should you buy?
The short answer
Buy as narrow as your trip allows. Single-country plans are cheapest per gigabyte, regional plans (Europe, Asia) are worth the small premium for multi-country trips, and global plans only pay off for genuine multi-continent itineraries or frequent unpredictable travel.
In detail
eSIM pricing follows a simple ladder. The wider the coverage, the more you pay per gigabyte. A single-country bundle for Spain costs less than a Europe bundle, which costs less than a global one. So the buying logic is to match the footprint to the itinerary, not to buy flexibility you will not use.
One country, even for three weeks? Country plan, no contest. The classic multi-country holiday (a Europe rail trip, an Asia hop)? Regional plan, because one eSIM crossing every border beats juggling three country bundles, and the premium over single-country pricing is modest at Airalo, Saily, and friends. Genuine globe-trotting (a conference in the US, then clients in Asia, then home via the Gulf)? That is what global plans from GigSky, BNESIM, or a pay-as-you-go wallet like Roamless exist for. Per-gigabyte they are the priciest tier, but one working setup everywhere has its own value.
Two checks remain before paying. The exact country list (regional plans differ on edge cases like Turkey in "Europe" or China in "Asia"), and whether your route's main country rides a good local network on that plan. When in doubt, narrow plus a small top-up later beats wide and wasted.