International data plans — whether a roaming add-on, local SIM, or eSIM — can range from $2/day to $15/day for the same usage. Picking the wrong option means overpaying or arriving with no connectivity. This guide compares all options by destination so you stay connected at the lowest cost.
Find Your Best Data Option
Option Types at a Glance
| Option | Typical Cost | Setup | Best For |
|---|---|---|---|
| eSIM (Airalo, Holafly) | $2-6/day | App, instant | eSIM phones, quick trips |
| Local SIM card | $1-5/day | Airport/store, 30 min | Longer stays, best value |
| Carrier roaming add-on | $5-15/day | App, pre-trip | Weekend trips, convenience |
| Pocket WiFi rental | $5-12/day | Airport pickup | Groups sharing data |
| No plan (hotel/cafe WiFi) | Free | None | Ultra-light travelers only |
| Default international roaming | $5-25/MB | None (dangerous) | Never — turn data roaming OFF |
How to Choose an International Data Plan
The single biggest mistake travelers make is forgetting to disable data roaming before landing abroad. Default international roaming from major carriers can charge $10-25 per megabyte — a single Google Maps refresh costs more than an entire day of eSIM data. The first thing to do when planning any international trip is sort your data plan.
Step 1: Check if Your Phone Supports eSIM
iPhone XS (2018) and later support eSIM. Most flagship Android phones from 2019 onward (Samsung Galaxy S20+, Google Pixel 3a+) also support eSIM. With eSIM, you can purchase a data plan via the Airalo or Holafly app before your trip and activate it the moment you land without touching your physical SIM. This is the fastest and often cheapest option for shorter trips.
Best Value: Local SIM Card
For trips of a week or more, a local SIM card usually wins on value. In Thailand, a 30-day Tourist SIM with 15GB costs about 300 THB (~$9). In the UK, a Three or Smarty SIM with 5GB is around £5. The tradeoff: you need to pick it up at the airport or a phone shop, and ID verification is required in some countries (Japan, India). Get an unlocked phone or check if your carrier offers unlocking before you travel.
Carrier Add-Ons: Convenient but Expensive
US carriers like T-Mobile (free international data in 210+ countries, albeit slow), AT&T ($10/day International Day Pass), and Verizon ($10/day TravelPass) offer roaming add-ons. These work without any setup and keep your regular number, which is ideal for 2-3 day business trips. For anything longer, eSIM or local SIM is cheaper. T-Mobile's included international data is worth enabling just as a backup even if you get a local SIM.
Japan: Special Case
Japan requires a local address for SIM registration. Most tourists use pocket WiFi rentals (book at Narita Airport) or data-only SIMs (available at airport kiosks) that don't require voice capability. IIJmio and Docomo tourist SIMs are reliable options. eSIMs from Airalo or Japan-specific providers like iVideo work well for eSIM-capable phones and can be purchased before landing.
FAQ
Is this international data guide free?
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What is an eSIM and is it better than a local SIM?
An eSIM is a digital SIM that you activate via a QR code — no physical swap needed. Services like Airalo, Holafly, and Apple's International eSIM let you add a local data plan before you land. For trips under 2 weeks, eSIMs are often cheaper and more convenient than buying a local SIM. For trips over 3 weeks, a local SIM usually offers better value.
Is T-Mobile International Pass worth it?
T-Mobile's Magma MAX plan includes unlimited data in 215+ countries (though often throttled to 256Kbps unless you purchase the International Day Pass for $5/day for full speed). For light data users or short trips, the included international data is often sufficient. For heavy users or remote workers, upgrading to the day pass or getting an eSIM may be better.
How much does AT&T International Day Pass cost?
AT&T International Day Pass costs $12/day per line and activates automatically when you use your phone abroad in 210+ countries. It includes unlimited talk, text, and data (throttled after high usage) using your domestic plan. For trips of 3 days or less, this is usually competitive. For longer trips, eSIM or local SIM is cheaper.
What is the cheapest way to get data in Europe?
Options ranked by cost: (1) Local SIM on arrival ($10-20 for 10-30GB), (2) eSIM via Airalo or similar ($10-20 for 10GB), (3) T-Mobile plan with included international data (free but slow), (4) AT&T/Verizon day passes ($12-15/day for full speed). For trips over a week, local SIM or eSIM beats carrier day passes significantly.