Can I use my own phone in South Korea?
Short answer
Yes, and you may barely need data — free public Wi-Fi runs on subway trains, buses and in most cafés.
Coverage is the least of your problems
Signal is dense and reaches underground. A call does not drop on the subway, and trains and city buses carry free Wi-Fi as standard equipment rather than as a perk.
Cafés, convenience stores and public buildings add more. It is genuinely possible to travel here on public Wi-Fi alone, which is not true of most countries.
Getting a SIM or eSIM
Prepaid SIMs and eSIMs are sold at airport counters, in convenience stores and online before you arrive. An eSIM bought in advance is the least effort, and it activates on landing.
Check whether the plan includes a Korean phone number or is data-only. The price difference is small and the difference in what you can do is not.
The real obstacle is proving who you are
A large share of Korean apps and websites want a domestic phone number before they will let you register, because identity verification here is tied to your mobile account.
That affects ticket booking, some delivery services, and a range of things a traveller might reasonably want to use. A data-only tourist plan gives you excellent internet and none of this. If you intend to book anything through a Korean service, get a plan with a number.
Good to know
- Subway trains and city buses carry free Wi-Fi as standard
- Some SIM plans do include a Korean number — worth checking if you intend to book anything
Yes. A prepaid eSIM is usually far cheaper than roaming — but it gives you data only, not a Japanese number.
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.
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.
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.