Every price below was read off the selling page on 14 September 2026. Currency is kept as the seller quotes it.
The answer, first
Buy a data-only travel eSIM before you fly, and skip the airport counter. You do not need a Korean phone number for maps, the subway, or paying in shops. The cheapest capacity today is a 50 GB / 30-day plan at $23.99 — $0.48 per gigabyte (MobiMatter, checked 14 Sep 2026); Airalo’s 50 GB / 30 days is $49, or $0.98 per gigabyte. If you would rather not think about gigabytes, Trazy sells an unlimited SKT plan at $3.34 for one day and $17.80 for seven.
Two conditions decide everything. Your handset must be unlocked, and it must actually support eSIM — dial *#06# and look for an EID number starting with 89. If either fails, nothing on this page works and you should be looking at a physical SIM or a pocket router instead.
And there is one more thing worth knowing before you pay: the eSIM you buy as a visitor is not the eSIM Koreans buy. The two products share a name and almost nothing else. Four things go wrong for people who don’t know that, and all four are cheaper to avoid now than to fix in Seoul.
What goes wrong first
1. Inside Korea, moving an eSIM to a new phone costs money — every single time. Korean carriers bill ₩2,750 including VAT to reissue an eSIM profile whenever the handset changes, and the charge lands on the following month’s bill. That applies after a factory reset, after a repair that swaps the mainboard, and simply because you bought a new phone. It is not a one-off setup fee. LG U+ states the companion rule outright: once downloaded, the eSIM cannot be transferred to another device, and there is no refund or reissue if you delete it or the handset fails.
That is the opposite of how the same technology behaves in the United States. Swap an eSIM to a new phone through a US carrier’s own app and there is no extra charge; T-Mobile levies nothing separate to activate one. Korean carriers also demand the device identity up front — EID plus IMEI1 and IMEI2 — which is a registration step most visitors never touch.
Here is why that matters to you anyway. It explains the reputation. A traveler who reads that Korean eSIM is a bureaucratic nuisance and decides to skip it has read something true about a product they were never going to buy. The plan you purchase from a travel eSIM seller is a roaming profile. It lives on your phone, it follows you home, and nobody asks for your IMEI. Judge the two separately.
2. Data-only really does mean no calls, and some Korean services want a number. Ordering a taxi in Kakao T, getting food delivered, and a few restaurant waiting-list apps ask for phone verification. If you need that, a Korean number is the answer — but you cannot simply buy a normal Korean plan. Prepaid and postpaid sign-ups require a residence card, Korean-style identity verification, and a card or bank account issued in Korea. Without all three, the online option open to you is the operator’s traveler plan, and LG U+ and KT hand those over only after you present your passport at an airport counter. LGU+ also caps purchases at three items per passport.
The practical split: data-only eSIM if you just need to get around; a local voice SIM if you plan to book rides and order in.
3. Compatibility claims on the box are not compatibility on your handset. Korean sellers warn that some foreign models do not work at all — one operator’s English FAQ names Huawei, Xiaomi and Google Pixel among the problem handsets for physical SIMs. The *#06# check settles it for eSIM in about four seconds. Do it at home, not in the arrivals hall.
4. Your home SIM is not automatically safe. Roaming on your existing line is the lazy option, and it is the expensive one: one Korean carrier’s own roaming bundle runs about ₩29,000 for 3 GB. Worse, some carriers ship with a roaming-blocking service switched on, so you land, switch the phone on, and nothing connects. If you plan to roam, call your carrier and confirm roaming is actually enabled before you leave.
What it costs, per gigabyte
Sellers advertise the sticker price. Convert to a unit rate and the market splits wide open. On 14 September 2026 the spread from best to worst was more than eight to one.
| Plan | Price | Per GB |
|---|---|---|
| MobiMatter, 50 GB / 30 days | $23.99 | $0.48 |
| Airalo, 50 GB / 30 days | $49.00 | $0.98 |
| Orange, 20 GB / 30 days (30% off) | €20.99 | €1.05 |
| Orange, 30 GB / 30 days | €45.85 | €1.53 |
| Airalo, 20 GB / 30 days | $32.00 | $1.60 |
| Orange, 10 GB / 7 days | €15.99 | €1.60 |
| Airalo, 10 GB / 7 days | $19.00 | $1.90 |
| Airalo, 5 GB / 7 days | $10.00 | $2.00 |
| Orange, 5 GB / 7 days | €10.99 | €2.20 |
| Orange, 3 GB / 7 days | €7.99 | €2.66 |
| Airalo, 3 GB / 3 days | $8.00 | $2.67 |
| Airalo, 1 GB / 3 days | $4.00 | $4.00 |
The lesson is not “buy the biggest plan”. It is that the smallest plan is where the margin lives: 1 GB from Airalo costs $4.00 a gigabyte; 50 GB costs $0.98. If your trip needs more than about 3 GB, buying small is the expensive way to do it.
Unlimited plans do not convert to per-GB at all, so convert them to cost per day instead:
| Plan | Price | Per day |
|---|---|---|
| Trazy, SKT unlimited, 60 days | $36.47 | $0.61 |
| Trazy, SKT unlimited, 90 days | $54.61 | $0.61 |
| Holafly, unlimited, 30 days | $73.90 | $2.46 |
| Trazy, SKT unlimited, 7 days | $17.80 | $2.54 |
| Trazy, SKT unlimited, 5 days | $14.00 | $2.80 |
| LGU+, unlimited LTE, 5 days | ₩27,500 | ₩5,500 |
| Holafly, unlimited, 7 days | $27.50 | $3.93 |
| Trazy, SKT unlimited, 1 day | $3.34 | $3.34 |
| Holafly, unlimited, 3 days | $12.50 | $4.17 |
| Trip.com, day pass, from | $0.44 | $0.44 |
Trazy’s 60- and 90-day columns are worth a second look: $0.61 a day undercuts every metered plan in the table above, and both are the same SKT product as the one-day option at $3.34. Long validity is where unlimited pricing quietly collapses.
The dated price table
Nothing below is a memory. Each figure was on the seller’s page on 14 September 2026.
| Seller | Product | Plan shapes | Prices as checked 14 Sep 2026 |
|---|---|---|---|
| MobiMatter | eSIM Korea | fixed data, up to 50 GB / 30 days | from $0.50/GB; 50 GB / 30 days $23.99 |
| Trip.com | South Korea eSIM | 500 MB/day → unlimited, 1–30 days | from $0.44/day (4G SKT); $0.52/day (4G LTE); $0.54/day (5G/4G) |
| Airalo | South Korea eSIM | 1 GB → 50 GB | 1 GB/3 d $4.00 · 3 GB/3 d $8.00 · 3 GB/7 d $9.00 · 5 GB/7 d $10.00 · 10 GB/7 d $19.00 · 20 GB/15 d $31.00 · 20 GB/30 d $32.00 · 50 GB/30 d $49.00 |
| Trazy | SKT unlimited | 1 day → 90 days | 1 d $3.34 · 3 d $9.11 · 5 d $14.00 · 7 d $17.80 · 60 d $36.47 · 90 d $54.61 |
| Holafly | South Korea unlimited | 3 days → 30 days | 3 d $12.50 · 5 d $20.50 · 7 d $27.50 · 10 d $36.50 · 15 d $50.50 · 30 d $73.90 |
| LGU+ (official) | Korea eSIM, data-only | 1 day → 5 days + monthly | ₩6,500 / ₩12,000 / ₩18,000 / ₩23,000 / ₩27,500 for 1–5 days; unlimited from $4.50 |
| Orange | South Korea eSIM | 1 GB → 30 GB, plus 1-day unlimited | 1 GB/7 d €3.99 · 3 GB €7.99 · 5 GB €10.99 · 10 GB €15.99 · 10 GB/14 d €16.99 · 20 GB €20.99 (30% off, was €29.99) · 20 GB/30 d €30.99 · 30 GB €45.85 · 1 day unlimited €18.99 |
| esimkorea.net | city and regional plans | per-city, regional, global | Seoul / Jeju / Busan / Incheon from $4.99; Korea–Japan–China unlimited from $13.99; Asia unlimited from $12.99 |
Two things fall out of that table that the marketing pages do not say. First, the official carrier option is not automatically the premium one — LGU+’s own 1-day unlimited LTE is ₩6,500, which is competitive with the resellers, and its 3-day-and-up bundles throw in a free T-money card collected at the airport. Second, the reseller market is where the bargains are: the same 30-day window costs $23.99 from one seller and $49 from another.
Unlimited, metered, or both
The break-even is arithmetic, not vibes. Suppose you buy Airalo’s 20 GB / 30 days at $32. That is $1.07 a day across a 30-day trip, or $2.29 a day if you only stay 14 days. Holafly’s 7-day unlimited costs $3.93 a day; Trazy’s 7-day is $2.54 a day.
So: on a one-week trip, metered 20 GB at $32 ($4.57/day) loses to Trazy’s unlimited at $17.80. On a two-week trip the metered plan drops to $2.29 a day and wins. The crossover sits somewhere around ten days for a normal data appetite — and it moves if you tether a laptop, because tethering is what burns 20 GB in an afternoon.
Two hard limits to check before you trust an “unlimited” label: some plans meter the daily high-speed bucket and drop you to a crawl afterwards, and a few block hotspot use altogether. LGU+ promises “no speed cap, truly unlimited” on its LTE product; verify the tethering row on any plan you intend to share.
Setting it up: five minutes, and the two places it stalls
- Confirm the handset. Dial
*#06#. An EID starting with 89 means you are fine. - Buy before you fly, install on stable Wi-Fi. A dropped connection mid-download aborts the profile install.
- Install. On Android the path is Settings → Connections → SIM manager → Add eSIM; on iPhone it is Settings → Cellular → Add eSIM. Scan the QR code, or paste the activation code if the seller gives you one — scanning needs a second screen, and the paste route does not.
- Do not close the screen while it activates. It takes about a minute and cancelling it wastes the profile.
- Set the roles. Use the travel eSIM for mobile data and keep your home SIM active for calls and SMS. Then switch off data switching so the phone cannot quietly fall back to a roaming charge.
- Watch the clock on validity. LGU+ plans must be activated within 60 days of purchase; Trazy asks you to scan within 180 days; other sellers run their own windows. Buy too early and you can burn the plan before boarding.
Details that never make it into a plan comparison
- The Discover Seoul Pass bundles a free eSIM along with its attraction access — the pass’s own site states this. If you were going to buy the pass anyway, price the bundle before you buy a separate plan.
- Your transport card and your wallet can be one card. WowPass is a prepaid card carrying two separate balances — one that works exactly like a T-money transit card, one that works like a Korean debit card wherever domestic cards are accepted, which covers the shops that reject foreign cards. Buy it at the CU convenience stores in the arrivals hall; charge the transit balance in cash only, and top up the spending balance in the app with an international card. Foreign cash from 16 currencies can also be loaded at kiosks at Hongik University, Seoul Station, Gangnam and Myeongdong.
- Recharging T-money changed in 2026. International cards now work at the recharge machines — with a service charge attached. Bring some cash anyway; the machines that take foreign cards are not everywhere.
- Free Wi-Fi is genuinely usable: every subway station, the trains themselves, most buses, and most tourist districts. Treat it as a backup rather than a plan, because it is the reason some travelers arrive without any data at all and then queue at a kiosk.
- Airport to Seoul, four ways. All-stop train ₩4,500, roughly an hour, and no luggage racks. Express train ₩9,500, about 45 minutes from Terminal 1 to Seoul Station, reserved seat and luggage storage included. Airport bus around ₩15,000, about 90 minutes, and the one to pick if you are hauling a suitcase. Taxis cost the most.
- Never take a taxi from someone who approaches you inside the terminal. Go to the official stand, and check that the meter starts.
- Cash: ₩100,000 covers a short trip, ₩250,000 if you are staying a week or more. Withdraw from the major bank ATMs — KB, Shinhan, Woori, Hana — rather than the third-party machines, which charge more. Exchange only ₩30,000–50,000 at the airport to get into town, then use the counters downtown. Myeongdong has the most competitive rates precisely because it has so many of them.
- Wear your hotel’s name and address in Korean, on screen. Taxi drivers will not read a Latin-alphabet address aloud, and showing one on a phone saves a five-minute pantomime at every trip.
- Taxi lights, decoded: red means the cab is empty and available, green means it is reserved for someone else, blue or dark means it is off duty.
- Money-saving edge that locals use: 24-hour saunas, called jjimjilbangs, take overnight guests on very tight budgets — not for a whole trip, but useful for one long layover.
- Navigation is a two-app job. The local apps own turn-by-turn directions in Korea because of map-data licensing. But for tourist-friendly restaurants — vegetarian, vegan, halal in particular — the international app is the one with usable ratings. Use each for what it is good at instead of arguing about which is better.
- Translation: test both before you trust one. The two long-term resident views do not agree. One swears by Papago and finds the other app’s output awkward in both directions; the other now prefers the international app because it improved sharply. Install both, and keep the offline language pack downloaded for the day the signal drops.
- Reviews are gameable. Some Korean restaurants trade free sides for five-star ratings, so treat everything above roughly 4.2 as the same score and judge on review count and photos instead.
Pick by trip shape, then stop
A week of city travel with no phone calls: one travel eSIM, installed on your own Wi-Fi, under $20. Two weeks or more: metered 20–50 GB and watch the unit rate fall. Rides and food delivery in the plan: add a traveler voice plan, and expect the passport check at the airport. Longer stays: the long-validity unlimited tiers beat every metered plan per day, and nobody expects you to use all of it.
That settles connectivity in about ten minutes. Where you sleep shapes the other 23 hours — Myeongdong puts the currency counters, the subway and the shopping in one walkable triangle, which is why it is the default for a first trip. Our 明洞住宿推薦 guide covers the three that are worth the money, and what to check before booking.
Land with data. Everything else in Korea is downhill from there.