Search for an eSIM for Spain and the same three or four names keep coming back. They are not variations on one product — Airalo, Holafly and VamosData sell structurally different things, and the right answer depends less on who is cheapest this week than on which shape fits your trip.

Declaring the obvious bias first: we are one of the three. So this stays on facts you can check yourself on each provider's own page, and we don't quote anybody's prices — including ours. Line-ups change weekly, and a price printed in a blog post is wrong by the time you read it.
First: do you even need one?
If your line is from an EU or EEA country, "roam like at home" already covers Spain at your domestic rates. Check your operator's fair-use cap before assuming it covers a long trip, but for a week in Madrid you may need nothing at all. We wrote about where that rule stops working.
Everyone else — UK lines since Brexit, and anything from the Americas, Asia, Africa or Oceania — is on international roaming rates, which is the whole reason this comparison exists.
The three, in one line each
Holafly sells Spain as unlimited data priced by the number of days you choose. There are no gigabyte-sized Spain plans; you pick a duration. It is data-only with no local number, and hotspot sharing is capped at 1 GB per day (their own page, checked October 2026).
Airalo is the big catalogue: fixed-data packages with a set validity for Spain, alongside regional and global options and some unlimited choices, bought and topped up in their app.
VamosData sells sized plans too, bought on the web with no app to install, and leans on matching the size to real use rather than selling you a day rate. Data-only, toppable up from your account on most plans, and run by a small independent business registered in Spain.
What actually differs
| Holafly | Airalo | VamosData | |
|---|---|---|---|
| Spain plan model | Unlimited, priced per day | Fixed data for a set validity (plus some unlimited) | Fixed data for a set validity |
| Where you buy and manage it | App or web | App-centred | Web — no app needed |
| Hotspot | Shared data capped daily | Depends on the package | Depends on the plan |
| Phone number | No — data only | No — data only | No — data only |
| Running low | Buy again | Top up in the app where offered | Email alert at about 80%, with a link showing what's left without logging in |
Two rows there matter more than they look. "Unlimited" is a commercial word, not a technical one — every provider that sells it has a fair-use policy behind it, which is worth understanding before you pay for it. And an app is a dependency: it is convenient until you need it at an airport on a dying battery, which is one reason a VamosData eSIM is managed in a browser.
How to choose, honestly
Heavy user, long stay, tethering a laptop. Unlimited-by-the-day is a reasonable buy, and Holafly is built for exactly that reader. Check the hotspot cap against how you actually work.
Normal traveller — maps, messages, a few reels, some photo uploads. A sized plan wins, because you are buying an amount rather than a day rate. If you have never counted, our day-by-day breakdown by traveller type is a better guide than guessing, and every VamosData country page has a plan finder that asks four questions and points at a size.
Spain plus three other countries. Stop comparing single-country plans and look at regional ones on all three. A VamosData regional plan keeps one setup running across the route; see what is live on the destinations page.
Months in one place. Honestly, consider a Spanish prepaid SIM once you land — we argued that case here. Arrive on a VamosData eSIM, then decide with working data in your hand.
Where we are different
Two things are structural rather than promotional. First, VamosData is a small independent business registered in Spain, in the Canary Islands, and the site and every email it sends you come in five languages. Second, the refund policy is written down rather than implied: a plan that has not been installed or activated, and is still inside its validity period, is refunded in full (terms, section 10). That matters in a market where "no refunds after purchase" is common.
Before you buy anything
Three checks, five minutes total. Confirm your handset supports eSIM on the device checker — that is a property of your phone, not of any plan. Install before you fly, on home Wi-Fi, using the iOS or Android guide. And remember a data-only line needs data roaming switched on to work at all — the single most common reason a perfectly good eSIM looks broken on arrival.
Then compare the live prices the same day, for your real trip length, across all three. Ours for Spain are on the Spain eSIM page.