Is there a free eSIM for travel, and is the free data actually usable?
The short answer
Yes. Firsty gives free, ad-supported data at reduced speed in most countries, and it is the only genuinely free tier on our shortlist. That is enough for maps and messages, not for video. Free data you earn by watching ads lasts seven days, and unlimited data at full speed costs from €2 a day.
In detail
Free here means one specific thing. Firsty's free tier is ad-supported and deliberately slow, so it carries messaging, maps and a boarding pass, but not streaming or video calls. The eSIM itself can sit unused on your phone between trips, while free data you earn by watching ads lasts seven days.
When the free lane is too slow you buy a day of speed instead of a bundle. Unlimited data at full speed starts at €2 a day. You pay on the days you need speed, and nothing on the rest.
Two other providers get close to free from a different direction. Instabridge is free to use as a crowdsourced map of millions of free Wi-Fi hotspots, and sells data on the side, for Europe in packs from 1 GB for seven days up to 10 GB for 30 days, priced in euros.
Roamless is built around a wallet rather than bundles. You load credit and pay per gigabyte used at the local rate, and the credit does not expire. You never pay for gigabytes you did not burn, which is as close to free as light users get.
The practical move is to treat free data as insurance rather than as the plan. Install Firsty at home next to your paid eSIM, and if the paid profile refuses to connect on arrival you still have a slow lane for the app, a map, or your hotel.
Who should not lean on it? Anyone tethering a laptop, taking video calls, or working while traveling. The free lane will not carry that, and buying speed every single day adds up faster than people expect.
The arithmetic is quick. Fourteen days at €2 cost at least €28, while a 5 GB / 30-day Europe bundle runs $16.99 at GigSky and $19.49 at Saily. On a two-week trip the bundle is the cheaper base and Firsty is the safety net.