Two separate things get confused under the heading of staying connected. One is getting a data signal, which in Korea is easy and almost impossible to get badly wrong. The other is being able to sign up for Korean services, which is a different problem with a different solution. The second half matters more than most visitors expect.
Three Ways to Get Data, Suited to Different People
You have three real options: a prepaid physical SIM, an eSIM, or a rented pocket wifi router. They are not ranked from worst to best. They suit different travellers, and picking the wrong one is the usual cause of complaint.
- Prepaid SIM — a physical card you swap in. Best if your phone is older, locked to a carrier, or does not support eSIM.
- eSIM — a digital profile you install by scanning a code. Best for a solo traveller with a recent, unlocked phone.
- Pocket wifi router — a rented battery-powered hotspot. Best for a family or group sharing one connection across several devices.
If you are travelling alone with a recent unlocked handset, an eSIM is almost always the least trouble. If there are four of you, one router beats four SIMs. Everything below is detail on those three cases.
The Prepaid SIM and What It Requires
Bring your passport. Korean mobile lines must be registered to an identified person, and this applies to tourist SIMs too, so the shop will scan your passport as part of the sale. There is no informal version of it.
The easiest place to buy one is the arrivals floor at Incheon or Gimhae airport, where the counters are signed in English and staff handle foreign visitors constantly. In the city, mobile phone shops and some larger convenience store branches also sell them, and convenience stores will top up a prepaid account at the till afterwards.
There are three carriers — SK Telecom, KT and LG U+ — and tourist products are resold under various brand names on top of those networks. Coverage on all three is unusually thorough, extending through subway tunnels, up mountains and along motorways, so the choice between them matters far less here than at home. What differs between products is the data allowance and whether outbound Korean calls are included.
eSIM: the Same Networks Without the Card
An eSIM runs on those same three carrier networks. The difference is delivery: you buy it online, receive a QR code, and install the profile over wifi, often before you leave home. There is no counter to find on arrival and no small plastic card to keep track of.
The real advantage is that your existing number stays active alongside it. Your home line keeps receiving messages and verification codes while the Korean profile carries your data, and that matters more than it sounds — see the section on phone numbers below.
Two things to confirm before buying, because neither is refundable afterwards. Your handset must support eSIM, and it must not be carrier-locked. Check both with your own provider rather than assuming, as a locked phone will accept the purchase and then refuse to activate the profile.
Pocket Wifi, and Who It Is Actually For
A pocket wifi router, called an 에그 (egeu, "egg") in Korean, is a small rented device that takes one mobile data connection and shares it as a wifi network for several devices at once. You collect it at the airport and return it there.
For a family or a group of friends this is the sensible answer. One rental covers everyone's phones plus a laptop, nobody swaps SIMs, and there is nothing to configure beyond a password.
The trade-offs are practical. It is another device to charge every night and it must be handed back on schedule. More importantly it only covers people standing near it, so the moment the group splits up for an afternoon, only whoever is holding it stays online. For a solo traveller it is the wrong tool.
Public Wifi Is Dense Enough to Rely On
Free public wifi in Korea is unusually widespread, and unlike the token provision in many countries it is worth connecting to. Government-backed hotspots signposted Public WiFi Free cover stations, libraries, community centres, buses and many public buildings. Subway platforms and trains carry their own networks.
Cafés almost always offer wifi, with the password printed on the receipt or posted near the counter. Asking is routine: 와이파이 비밀번호 (waipai bimilbeonho) is the wifi password, and pointing at your phone while saying it will get you there.
The limitation is movement. Public networks are excellent while you are sitting still and useless while you are walking somewhere you cannot find. Treat them as a way to reduce how much mobile data you buy, not a replacement for having any.
Why a Korean Phone Number Still Matters
This is the constraint that surprises people, and it has nothing to do with signal strength. Many Korean services require 본인인증 (bonin injeung), identity verification, which sends a code to a mobile number registered to a named person in Korea. A foreign number cannot complete it.
What this blocks is narrower than it sounds. Everyday tools — maps, messaging, translation — sign up perfectly well with an email address or a foreign number. What tends to require verification is domestic ticketing, some delivery platforms, certain reservation systems and anything adjacent to banking.
The workarounds are modest. Many services run an international-facing version of the same site that skips verification. For the occasional booking that insists, a guesthouse host or a Korean friend can complete it, and asking is a normal request rather than an imposition. Anyone staying long enough to hold a residence card stops having this problem entirely.
The Map Problem, and What Koreans Use Instead
Google Maps works in Korea for searching landmarks and for basic public transport routing, so it is not useless. But walking directions are patchy and driving navigation is largely absent, which is why visitors relying on it end up circling a block looking for an entrance.
The cause is regulatory rather than technical. South Korea restricts the export of detailed mapping data, and because Google processes its map data on servers outside the country, it cannot use the fine-grained road information that turn-by-turn navigation needs.
What Koreans use is Naver Map or Kakao Map. Both have English interfaces, both do walking, driving and transit properly, and both carry building-level detail — which floor a restaurant is on, which subway exit to take. Install one before you arrive and treat it as the default, alongside our public transport guide.
Messaging Runs Through KakaoTalk
KakaoTalk, 카카오톡 (kakaotok), is not merely the most popular messaging app in Korea. It is the assumed default, in the way a phone number is assumed elsewhere. Registration accepts foreign numbers, so this is one Korean service genuinely open to visitors.
In practice it is how a guesthouse host, a tour operator or someone you met at dinner will expect to stay in contact. Many small businesses answer a Kakao message faster than a phone call, and text is far easier than speech when your Korean is limited, because you can paste either side into a translator.
Translation, and the Payment App Limit
For translation, Papago handles Korean better than general-purpose tools, particularly the compressed phrasing on menus and signs. Its camera mode overlays a translation onto printed text, which works well on menus, product labels and station signage, though it struggles with handwriting and decorative fonts. Download the offline Korean pack before you travel — it is the difference between a working translator and a blank screen in a basement with no signal. Being able to sound out Hangul makes its mistranslations easier to catch.
Payment apps are where to lower expectations. KakaoPay, Naver Pay and the domestic QR schemes are built around a Korean bank account or a Korean-issued card, and a foreign card generally cannot be added. This is a design of the domestic financial system rather than an oversight.
The workable approach is unglamorous: carry a physical card, which is accepted almost everywhere including taxis and small shops, and keep some cash for transit card top-ups, traditional markets and street food stalls. That is what most visitors settle into by the second day.
