My quick recommendation
For most travellers with an unlocked, eSIM-compatible phone, an eSIM is the lowest-friction choice: install it before departure, keep your home SIM in the phone, and switch the data line on after landing. If your phone does not support eSIM, a prepaid physical SIM from a Korean carrier or tourist SIM seller is the obvious alternative. A pocket Wi-Fi device still makes sense for a family or group that wants to share one data connection.
Roaming is the convenience option. It can be perfectly sensible for a very short trip if your home carrier has a good Korea package, but I would compare the actual total price rather than assuming roaming is automatically expensive or automatically easiest.
eSIM: easiest when your phone supports it
An eSIM is a digital SIM profile installed by QR code or an app. Korea Tourism Organization currently lists prepaid eSIMs alongside tourist SIMs and Wi-Fi rentals as normal visitor connectivity options. The important checks happen before you buy: confirm the exact phone model supports eSIM, confirm the handset is carrier-unlocked, and check whether the plan is data-only or includes a Korean voice/SMS number.
A data-only eSIM is enough for maps, messaging and web browsing. A Korean number can still be useful for certain bookings or local services, but having a number does not automatically mean every Korean app will accept you for identity-verified services. I would not choose a more expensive plan solely on the assumption that it unlocks every local app.
Physical tourist SIM: still a very solid option
If you want a conventional SIM, Korea Tourism Organization says traveller SIMs are available at major airports and through convenience stores and specialist sellers. Incheon and other major airports also have carrier roaming centres where visitors can arrange SIMs, roaming and Wi-Fi devices.
The trade-off is physical handling: you need an unlocked phone, the right SIM size, and somewhere safe for your home SIM if the phone has only one physical slot. The upside is that setup can be done with staff assistance at the airport instead of troubleshooting a QR code after a long flight.
Pocket Wi-Fi: best when several devices share one connection
A pocket Wi-Fi unit — often called a Wi-Fi egg — is a small rechargeable hotspot. It can be good value when two or more people want to share data, or when a child has a Wi-Fi-only tablet. It also avoids changing the SIM configuration on each phone.
The nuisance is the extra object: it needs charging, everybody has to stay within range of it, and a rental usually needs collection and return. If the person carrying the hotspot disappears into another subway carriage, the rest of the group briefly discovers the weakness in the “one device for everyone” strategy.
International roaming: pay for convenience, but check the maths
Home-carrier roaming keeps your normal number and requires almost no setup. That is useful for a two- or three-day stop, business travel, or anyone who values continuity more than saving a few dollars. Before relying on it, check the daily fee, data allowance, fair-use throttling and whether the pass starts automatically when the phone connects in Korea.
I also disable unnecessary background downloads and cloud-photo syncing until I know exactly what the plan includes. A “daily roaming pass” can be good value; accidental pay-as-you-go roaming generally is not.
Free Seoul Wi-Fi is genuinely useful — as backup
Seoul operates public Wi-Fi across many public facilities and outdoor locations, while Korea Tourism Organization notes free Wi-Fi in places such as airports, subway and rail stations and other public spaces. Cafes and hotels add another layer of coverage.
I would still buy reliable mobile data. Public Wi-Fi is excellent when you need to conserve data or rescue a connection, but your most awkward moments tend to happen between stations, outside a closed attraction, or while trying to show a driver an address. That is exactly when you do not want your navigation plan to depend on finding an SSID.
Set it up before you actually need it
- Before flying: confirm your phone is unlocked, install the eSIM if the provider allows it, and save the activation instructions offline.
- At the airport: if using a physical SIM or pocket Wi-Fi, test data before leaving the arrivals area.
- On the phone: know which line is being used for mobile data and whether data roaming must be enabled for the travel eSIM.
- As backup: save your hotel address in Korean and English and download the key information you would hate to lose without data.
Do you need a Korean phone number?
Many short-stay travellers do not. Messaging apps, map apps and ordinary web bookings work fine with data. A local number becomes more useful if you are staying longer, arranging local deliveries, dealing with accommodation hosts, or using services that send Korean SMS verification codes.
Even then, a tourist number is not the same thing as Korean resident identity verification. I treat “includes a Korean number” as a communications feature, not a magic key to every local platform.
One current wrinkle: some tourist passes bundle data
The current Discover Seoul Pass product includes a limited-period unlimited-data eSIM benefit on some pass types. That can change, and the pass only makes sense if the attractions/transport benefits suit your itinerary anyway, so I would check the current inclusions instead of buying an attraction pass purely for connectivity.
Official sources I would check before buying
- Korea Tourism Organization — Electricity & Communications for current SIM, eSIM, roaming-centre and public Wi-Fi guidance.
- Korea Tourism Organization — 1330 Travel Helpline for current multilingual traveller support.
Cheers, Carpe Diem & stay connected without turning arrival day into tech support! 🍻⏳📶
TATS Man
Your QR-code-checking, roaming-fee-reading Seoul connection mate.