Can I use my own phone in China?
Short answer
Yes, but decide how before you fly. A local SIM has to be registered against your passport, and a number of services you use daily will not load.
A local SIM means registration
Mobile numbers are tied to identity by regulation, so buying a SIM is not an over-the-counter transaction. You present your passport, it is recorded, and the number is issued against it.
That is straightforward at an airport or carrier shop and impossible from a vending machine. Budget the time on arrival rather than assuming you can grab one on the way to the train.
What will not load
A range of services that are ordinary elsewhere — some search, mail, mapping, social and messaging platforms — are not reachable from a domestic connection. Planning around that matters more than the connection speed.
The practical consequence is boring but real: if your hotel booking, your boarding pass and your photos all live in the same account, check that you can still reach it before you need it at a counter.
Roaming and eSIM
International roaming from your home carrier keeps your usual number working and routes your data through the home network, which sidesteps the problem above. It is the least fiddly option and usually the most expensive.
An eSIM bought before departure sits between the two. Check what the plan actually routes through before buying on the assumption that it behaves like roaming.
Good to know
- Download offline maps and save your booking confirmations as files before you land
- A SIM bought at the airport is registered on the spot — bring the passport you flew in on
Yes. A prepaid eSIM is usually far cheaper than roaming — but it gives you data only, not a Japanese number.
Yes, if the handset is unlocked — and bring your passport, because every SIM here is registered to a named person.
Buy a prepaid SIM on arrival with your passport — it is cheap, the coverage is good, and a local number is what makes the ride-hailing apps work.
Yes, and you may barely need data — free public Wi-Fi runs on subway trains, buses and in most cafés.
There is a genuine national free wifi network — iTaiwan, over 5,000 hotspots, and since 2020 no registration at all. Connect, open a browser, done.