Cheapest eSIM for Japan: the real price list
The cheapest way into Japan is £2.99 for 1 GB over 7 days. That is the entry price, not the best value — on a per-gigabyte basis the 20 GB plan works out about 70% cheaper per gigabyte. Here is the full list and how to choose between them.
Every Japan plan, cheapest first
| Data | Valid | Price | Per GB |
|---|---|---|---|
| 1 GB | 7 days | £2.99 | £2.99 / GB |
| 1 GB | 1 day | £3.49 | £3.49 / GB |
| 3 GB | 30 days | £5.99 | £2.00 / GB |
| 5 GB | 30 days | £7.99 | £1.60 / GB |
| 10 GB | 30 days | £12.99 | £1.30 / GB |
| 20 GB | 30 days | £17.99 | £0.90 / GB |
Live prices in GBP, updated from our network partners. 6 plans currently available for Japan.
Cheapest entry price vs best value
Those are two different questions and they have two different answers here. £2.99 is the least you can spend, and for a short trip where you mostly need maps and messaging it is often enough. But at £2.99 per gigabyte it is the most expensive data on the list.
The 20 GB plan at £17.99 works out to £0.90 per gigabyte, roughly 70% less. If there is any chance you will use more than 1 GB, buying the larger plan up front costs less than buying the small one twice.
The largest option is 20 GB at £17.99 — worth it for a long stay, tethering a laptop, or a trip where you are uploading photos and video rather than just checking directions.
How long the plans last
Validity in Japan runs from 1 day up to 30 days. Validity counts from activation, not purchase, so installing before you fly costs you nothing — the clock starts when the profile first connects to a network in Japan.
That is the single most useful thing to know about buying early: you can have the eSIM on the phone days ahead, with no penalty, and it only begins when you land.
A note on routing
Plans for Japan exit locally — your data leaves for the internet from Japan rather than being routed back through another country first. In practice that means lower latency and fewer oddities with services that check where you appear to be.
What you still need to check
Price is the easy part. Before buying any travel eSIM for Japan, confirm your phone supports eSIM (look for Add eSIM in Settings) and that it is not carrier-locked. iPhones bought in mainland China have no eSIM hardware at all, whatever the model. Full detail is in installing a travel eSIM on iPhone.
And if you are weighing this against an unlimited plan, fixed data or unlimited explains what a fair-use cap does to that comparison.