A practical starting point
For a one-week trip, 1–3 GB can be enough for maps, transport apps and messaging when hotel Wi-Fi covers heavier use. A regular traveller who also browses, uploads photos and uses social media may be more comfortable with 5–10 GB. Video streaming, tethering or remote work can justify 10–20 GB or more.
These are planning ranges, not guarantees. App settings, video quality, cloud backups and operating-system updates can change consumption dramatically.
- Light use: 1–3 GB per week
- Regular use: 5–10 GB per week
- Heavy use or hotspot: 10–20+ GB per week
What uses the most data?
Maps and text messaging are usually modest compared with video. High-resolution streaming, video calls and automatic photo backup can consume gigabytes quickly. Social feeds also preload video even when you do not open every clip.
Hotspot use deserves special attention because a laptop may download updates, synchronize cloud folders and load desktop-quality media. Check whether the selected plan permits tethering and whether a fair-use limit applies.
Estimate from your current phone
Both iPhone and Android show mobile-data usage by app. Reset the statistics or note the current total, use the phone normally for several days, then divide by the number of days. Add a buffer for airport navigation, translation, ride-hailing and unexpected time away from Wi-Fi.
Do not count months of historical usage without checking the reset date. The useful figure is average daily mobile data under travel-like conditions.
Make a smaller plan last longer
Download offline maps, music and entertainment before departure. Disable mobile data for cloud photo backup and app-store updates. Set video quality to standard definition and use trusted Wi-Fi for large files.
On dual-SIM phones, confirm that mobile-data switching is disabled if it could move traffic back to the expensive primary SIM when the travel eSIM loses signal.
When to choose a top-up-capable plan
If usage is unpredictable, a smaller plan with confirmed top-up support can be safer than buying the largest option immediately. Top-ups are tied to the original provider package and ICCID, so availability must be shown for the exact plan.
When a package cannot be topped up, additional data normally requires a new eSIM. Keep the original profile installed until its trip is complete.