Three ways to have working data abroad: pay your home carrier to roam, buy a SIM when you land, or install a travel eSIM before you go. They differ less in technology than in how you get billed and how much of your holiday you spend sorting it out.
Home-carrier roaming
The simplest and usually the most expensive. Your phone keeps working the moment you land, with your number and your plan, and your carrier bills you for the privilege in one of three shapes:
- A daily pass. A flat fee for each day you use data abroad, often in the region of a few dollars or pounds, sometimes drawn from your home allowance. Convenient, and the cost is predictable, but you pay for the whole day even if you only checked a map once.
- A bundled allowance. Some plans include roaming in certain regions. Genuinely good value when your destination is on the list. Check the list, not the marketing.
- Pay as you go. The one that produces the stories. Per-megabyte pricing with no cap is how a weekend abroad turns into a four-figure bill.
Ask your carrier two questions before you travel: what does data cost per day or per megabyte at this destination, and is there a spend cap. If the answer to the second is no, treat the first as unlimited downside.
A local SIM bought at the destination
The cheapest data per gigabyte, almost everywhere. The costs are not on the price tag:
- You need an unlocked phone and, in many countries, to register the SIM against your passport before it works.
- You lose your own number for the trip unless your phone takes two SIMs, so two-factor codes sent by SMS stop arriving.
- You spend part of your first day queueing at an airport counter, usually at the worst exchange rate available.
Worth it for long stays. Rarely worth it for a week.
A travel eSIM
A data plan you buy online and install as a second line on your phone, keeping your usual SIM for calls and texts. No queue, no passport counter, and your number stays where it is.
The trade-offs are real and worth stating plainly:
- Data only. Travel eSIM plans do not carry your voice calls or SMS. Calls over WhatsApp, FaceTime or Telegram work fine because they are data. Regular calls still use your home SIM, at your carrier’s roaming rates.
- The phone has to support eSIM and be carrier-unlocked. Most phones sold since 2019 do. Check yours in a minute.
- You have to install it while you have internet. Do it on Wi-Fi before you fly. An eSIM also installs only once, so do not delete the profile while you still need the data.
How to pick, in one paragraph
If your carrier includes your destination in your plan, use it and stop reading. If you are staying for a month or more in one country and can live without your number, a local SIM is cheapest. For everything in between, which is most trips, a travel eSIM costs less than a roaming pass, takes about a minute to set up and leaves your number alone.
What it costs with us
Vayufly plans start at $0.60, and you can see every plan for a destination, with its data allowance and validity, before you buy. A short city break usually needs far less data than people expect: our guide to how much data you actually need works it out by activity.
Browse destinations to see live prices, or get the app to keep your eSIMs, usage and alerts in one place.