eSIM plans are usually sold in neat tiers — 1GB, 5GB, 10GB, unlimited — which makes the decision feel harder than it is. The honest answer depends less on trip length and more on how you'll actually use your phone once you land.
The short answer: how many GB do you need?
Most travelers use about 0.5 to 1 GB of data per day. That works out to roughly 5 GB for a one-week trip and 10 GB for two weeks with normal use: maps, messaging, some social media, and the occasional video call. If you mostly use maps and messaging, half that is often enough. If you stream video or work from your phone, plan on double.
What actually eats data while traveling
Maps and messaging apps use very little. The real data drains are: navigation with live traffic running in the background all day, streaming music or video over cellular instead of downloading it beforehand, video calls home, and posting photos/video to social media in real time. If you do all four daily, you'll burn through data much faster than someone using their phone mainly for maps and texting.
Roughly how much data common apps use
| Activity | Approximate data use |
|---|---|
| Messaging (WhatsApp, iMessage, text only) | Very little: a few MB a day |
| Google Maps or Apple Maps navigation | Low: usually under 10 MB per hour of driving or walking |
| Web browsing and email | Low to moderate: around 50 to 100 MB per hour |
| Music streaming | Around 50 to 150 MB per hour, depending on quality |
| Scrolling Instagram or TikTok | High: several hundred MB per hour, mostly video |
| Video calls | High: around 300 MB to 1 GB per hour |
| Streaming video (Netflix, YouTube) | Very high: about 1 GB per hour in standard quality, more in HD |
These are rough figures and vary by app settings and video quality. Downloading offline maps and playlists on hotel Wi-Fi before you go out cuts your usage a lot.
A rough sizing guide by trip length
| Trip length | Light use | Normal use | Heavy use |
|---|---|---|---|
| Weekend (2–3 days) | 1 GB | 2–3 GB | 5 GB |
| 1 week | 2–3 GB | 5 GB | 10 GB |
| 2 weeks | 5 GB | 10 GB | 20 GB |
| 1 month | 10 GB | 20 GB | Unlimited |
"Light use" means maps plus occasional messaging. "Normal use" adds regular social media browsing and some music streaming. "Heavy use" assumes daily video calls, streaming, or working remotely off your phone's hotspot.
Why buying slightly less than you think is usually fine
Most eSIM providers let you top up the same plan instantly from the app if you're about to run out — you don't need a new QR code or a fresh install. That means the real cost of underestimating is a two-minute top-up, while the real cost of overestimating is money spent on data that just expires unused. When in doubt, it's usually cheaper to buy one size down and top up once, than to buy the largest plan "just in case."
One thing worth checking before you buy
Not every plan covers every country the same way — some are single-country, some cover a whole region (like all of Europe), and coverage quality can vary by carrier partnership in that specific destination. Always confirm your destination is fully covered before checkout, especially if your trip crosses multiple countries.
Once you know roughly what size you need, you can compare plans by country or region and get connected before you even land.
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