South Korea is one of the cheapest countries in the world to buy travel data for, and one of the easiest to overpay in. The table below is the first half of the answer: our live prices for South Korea next to Airalo’s published ones, read from their own product page on the date shown. We are cheaper on every row the two of us both sell, and the gap is widest on the sizes most people actually buy. The second half is the part no price table can show you. Three decisions cost travellers more than the provider they choose. They buy a regional Asia plan that does not include South Korea at all. They buy the plan that spans Japan and Korea because one eSIM sounds simpler than two, when two country plans give more data for less money. And they buy too little data for a country where the map app they use everywhere else cannot give them directions. This guide takes those in order, with the arithmetic shown rather than asserted, and ends with what to buy for the length of trip you are actually taking.
How the prices compare for South Korea
Lumbus prices are live from our catalogue. Airalo prices are the public list prices on their own websites, in US dollars, checked on 18 September 2026. Where another provider is cheaper, the table says so.
| Plan | Lumbuslive price | Airalo |
|---|---|---|
| 1GB | $3.99 · 7 days$3.99/GBCheapest | $4.00 · 3 days$4.00/GB |
| 3GB | $4.99 · 30 days$1.66/GBCheapest | $9.00 · 7 days$3.00/GB |
| 5GB | $5.99 · 30 days$1.20/GBCheapest | $11.00 · 30 days$2.20/GB |
| 10GB | $8.99 · 30 days$0.90/GBCheapest | $19.00 · 30 days$1.90/GB |
| 20GB | $15.99 · 30 days$0.80/GBCheapest | $30.00 · 30 days$1.50/GB |
| Unlimited · 7 days | $19.99 · 7 days$2.86/day3GB/day at full speed, then 1MbpsCheapest | $29.00 · 7 days$4.14/day3GB/day at full speed, then 1Mbps |
| Unlimited · 30 days | $62.99 · 30 days$2.10/day3GB/day at full speed, then 1MbpsCheapest | $69.00 · 30 days$2.30/day3GB/day at full speed, then 1Mbps |
Lumbus is the cheapest option in 7 of the 7 plans compared.
Not in this table yet: Holafly, Saily, and Nomad. Their prices are added once checked.
Price pages checked: Airalo (18 September 2026)
Read the days column, not just the price
The table sorts by how much data you get, but the number that catches people out is the validity next to it. At three gigabytes, the comparable plan on the other side runs for a week. Ours runs for a month and still costs a little over half as much. That is two differences stacked in the same row, and only one of them is a price.
The pattern holds as the sizes go up. At ten gigabytes for a month, the widely bought size for a one- or two-week trip, ours is less than half. At five and at twenty it is a little over half. At one gigabyte the prices are within a penny of each other, and the difference is the validity again: a week rather than three days.
Where the gap closes is unlimited. At seven days ours is roughly a third cheaper. At thirty days the two are within a tenth of each other, which for practical purposes is the same price. If a month of unlimited data is what you want, price is not a good reason to pick either of us, and you should choose on whatever else matters to you.
One thing the table cannot show is that "unlimited" means the same thing on both sides here. Both products give you a fixed allowance each day at full speed, then keep working at a reduced speed until the allowance resets the next day. The daily allowance and the reduced speed are identical on both. Nobody is offering more unlimited than anybody else in South Korea.
The cheapest Asia plan does not include South Korea
A regional plan covers a list of countries, not a region on a map, and the cheapest Asia list is a Southeast Asia list wearing a wider name. It covers Vietnam, Indonesia, the Philippines, Cambodia, Thailand, Malaysia and Singapore. South Korea is not on it. Neither is Japan.
This is the single most expensive mistake on this page, because it is not a matter of paying more. It is landing at Incheon with an eSIM that will not connect, at the one moment you have no easy way to fix it.
The Asia lists that do carry South Korea start at twelve destinations and run up to a little over twenty. Those wider lists add China, Japan, Hong Kong, Taiwan and Macao at the smaller end, and India, Saudi Arabia, Pakistan and Central Asia at the wider end. They are real products and they are useful, but they are priced like what they are: for a month of ten gigabytes, the widest of them costs about five times the South Korea plan.
So the rule is short. Buy a wide Asia list when you are genuinely visiting several of the countries on it in one trip, and the alternative is three or four separate eSIMs. For a trip to South Korea, even one with a stopover somewhere, it is the wrong product.
- The cheapest Asia list: Vietnam, Indonesia, the Philippines, Cambodia, Thailand, Malaysia, Singapore. No Korea, no Japan, no China.
- The twelve-destination list adds China, Japan, Hong Kong, Taiwan, Macao and South Korea.
- The widest Asia lists add India, Pakistan, Saudi Arabia, Australia, New Zealand and the Central Asian countries.
- Before you pay for any regional plan, open its coverage list and find your destination by name.
Japan and Korea: two eSIMs beat the one that covers both
There is a plan built for exactly the trip a lot of people take: mainland China, Japan and South Korea on one eSIM. One purchase, one install, no switching at the border. It sounds obviously right, and for most itineraries the arithmetic says the opposite.
Take ten gigabytes for a month, the size most two-week trips land on. Japan and South Korea happen to be priced identically in our catalogue, and each country plan at that size costs a little under a third of the combined plan. Buy both instead, and you have two eSIMs carrying ten gigabytes each. That is twice the total data for around forty per cent less than the combined plan charges for ten.
Add mainland China and it gets starker rather than closer. Three country plans at ten gigabytes each come to within a couple of pennies of the three-country plan carrying ten gigabytes in total. Same money, three times the data, across the same three countries.
The combined plan does win in one narrow case: the very smallest size. If a single gigabyte is genuinely all you need for the whole trip, one eSIM carrying it costs less than two eSIMs carrying one each, because you are paying twice for a minimum rather than buying twice the data. Above that size it does not win again.
What you actually buy with the combined plan is convenience. One install, one profile, nothing to switch when you land in the next country. That is worth something on a tightly packed trip, and it is worth admitting that switching between two travel eSIMs is a few taps in your phone’s mobile data settings, not a reinstall. Decide on the convenience, not on a price advantage that is not there.
Google Maps still cannot give you directions in South Korea
This is the Korea-specific fact that changes how much data you should buy, and most travellers discover it on day one.
Google Maps works in South Korea as a search tool. It finds restaurants, shows opening hours and reviews, and puts pins on a map. What it does not do is navigate. There is no turn-by-turn driving navigation, and walking and transit directions are patchy to absent. The cause is a long-running restriction on exporting detailed Korean map data, kept in place on national security grounds for nearly two decades. In February 2026 the Korean government granted conditional approval for the data to leave the country, but as of this writing the navigation it would enable has not arrived. Plan for the country as it is today, and treat any improvement as a bonus.
What people use instead is Naver Map or Kakao Map. Both have English interfaces, both do transit, walking and driving properly, and both are built to run online. That matters for your data budget more than it sounds.
Everywhere else, the standard advice for saving data abroad is to download offline maps before you go and let the phone navigate without a connection. In South Korea that advice quietly stops working, because the app that offers offline maps is not the app that can direct you. Your navigation runs live, all day, on the days you walk the most.
Add the rest of the phone-shaped stack around it. Camera translation of menus and signs. A taxi app instead of explaining an address. Transit times that change. Tickets and entry passes on your screen. None of it is heavy on its own, and together it is why a week in Seoul draws more than the same week in a city where you could have cached the map.
Ten gigabytes is the quiet default, and why
For a week to ten days of ordinary sightseeing, ten gigabytes for a month is the size that fits almost everyone. It is not the cheapest line on the page and it is not meant to be. It is the one that stops you thinking about data for the rest of the trip.
The reason is the shape of the pricing rather than anything about Korea. Stepping up from five gigabytes to ten costs about half as much again and gives you double the data. That is the cheapest insurance on the page. Stepping from ten to twenty is less than double the price for double the data again, which is the size to take if you are hotspotting a second phone, travelling as a couple off one plan, or on the train between cities with a laptop open.
Below that, three gigabytes for a month is a real answer for a long weekend where you are mostly on hotel Wi-Fi and want maps and messaging in between. One gigabyte for a week is for a very short, very light trip, and it is easy to underestimate. If you are on the fence between the two, the gap between them is small enough that the larger one is the sensible mistake to make.
At the other end, fifty gigabytes over a month is the remote-working size: video calls, cloud sync, tethering a laptop most days. It costs a bit more than double the twenty for two and a half times the data.
And every one of these fixed sizes accepts a top-up. If you misjudge it you add data to the same eSIM rather than starting again, so the cost of guessing low is inconvenience, not a wasted purchase.
- Long weekend, hotel Wi-Fi most of the day: three gigabytes, thirty days.
- A week or ten days of sightseeing: ten gigabytes, thirty days.
- Two weeks, two cities, photos uploading and a hotspot on: twenty gigabytes.
- A month with a laptop and video calls: fifty gigabytes.
When unlimited is the right answer in Korea, and when it is not
Unlimited plans here are sold by the day: three, seven, fourteen or thirty days. Each day you get a full-speed allowance, and when it runs out the connection keeps working at a reduced speed until the clock rolls over and the allowance comes back. It is genuinely unlimited in the sense that it never cuts off. It is not unlimited in the sense of full speed forever, and that is true of every provider selling the word in South Korea, including the one in the table.
The daily full-speed allowance is generous for phone use and thin for laptop use. Maps, messaging, photos and a couple of hours of video will not reach it. A working day of tethering, a large cloud sync or a few hours of high-quality streaming will.
Then there is what it costs against the fixed sizes. A week of unlimited is about a quarter more than twenty gigabytes that lasts a full month. A month of unlimited is nearly twice the price of fifty gigabytes over that same month. Unless you are genuinely going to use more than fifty gigabytes in Korea, the fixed plan is the cheaper way to buy a lot of data.
So unlimited earns its place in three situations. You tether a laptop most days and cannot predict the load. You are shooting and uploading video. Or you simply do not want to watch a counter on holiday, and the difference is worth the peace of mind. All three are legitimate. "It sounds safer" is not, when the same money buys more data the other way.
One practical difference between the two shapes: a fixed plan takes a data top-up when you run low, while an unlimited plan is extended by adding days to it while it is still running. Neither is better, but they fail differently, and it is worth knowing which lever you have before you need it.
The networks you will actually be on
In South Korea your eSIM connects to LG Uplus and SKTelecom, with 5G where it is available. Those are two of the country’s three national networks, and both carry 5G in our coverage data. For a visitor walking around Seoul or Busan, the practical difference between the two is small.
There is nothing to configure. The phone scans both and settles on the stronger signal, and it will move between them on its own as you travel. You do not pick a network when you buy, and no honest provider can promise you a specific operator inside a specific building.
If the connection feels slow rather than absent, the first thing to try is airplane mode on and off. That forces a fresh network scan and fixes the most common complaint, which is a phone that latched onto a weak cell and stayed there. If it is still slow after that, it is worth checking whether your allowance has run down into the reduced-speed part of an unlimited day.
Buy before you fly, not at Incheon
The airport counter is not just slower, it is worse timed. You queue after a long-haul flight, with paperwork, to get something you could have set up on your sofa a week earlier.
A travel eSIM has two clocks and they are easy to mix up. The first is a shelf life: from purchase, the eSIM has a window in which it must make its first connection, and on every plan we sell that window is a hundred and eighty days. The second is the plan validity, the seven or thirty days of actual data. That one does not start when you buy and does not start when you install. It starts the first time the eSIM connects to a network in South Korea.
So the timing that works is: buy when you book, install a day or two before you fly while you are on home Wi-Fi, and land with it already sitting in your phone waiting for a signal. Installing does not spend any of your data and does not start the validity.
Buying early is also lower risk than it sounds. If the trip falls through and you have not installed the eSIM, it is refundable on a change of mind, and UK law gives you a fourteen-day cancellation right on digital content you have not installed. Once the eSIM is installed, that right is waived, which is the reason to install a couple of days before rather than the afternoon you buy.
What to buy, by the trip you are taking
The short answers, gathered in one place.
A layover of under a day at Incheon: the single-day option is the cheapest way to have maps and messaging in the city and back. Worth knowing that two days of it costs more than the three-gigabyte plan that runs a month, so it only makes sense for a genuinely short stop.
Four or five days in Seoul, mostly on foot, hotel Wi-Fi at night: three gigabytes over thirty days.
A week to ten days, the standard first trip, Seoul plus a day out: ten gigabytes over thirty days. This is the one to default to.
Two weeks with Busan or Jeju in it, photos uploading, a hotspot for a second device: twenty gigabytes.
A month, working as you go, laptop tethered: fifty gigabytes, or unlimited by the day if the load is unpredictable.
Japan and Korea on one trip: a country plan for each, not the combined one, unless you want the single install badly enough to pay for it.
Korea plus three or four other Asian countries: this is what the wide regional lists are for. Check your destinations are on the list by name before you pay.
Frequently asked questions
What is the best eSIM for South Korea?
For most trips it is a South Korea country plan rather than a regional Asia one, at ten gigabytes over thirty days. On the price comparison above, our South Korea plans are cheaper than Airalo’s on every size the two of us both sell, and the gap is widest at five, ten and twenty gigabytes. The exception is unlimited over a month, where the two are close enough that price should not decide it.
How much data do I need for a week in South Korea?
Ten gigabytes is the size that fits almost everyone for a week, and it is worth taking over five because the step up costs about half as much again for double the data. Korea pulls more than you might expect for one specific reason: Google Maps cannot navigate here, so you will be using Naver Map or Kakao Map live rather than a cached offline map. If you are on hotel Wi-Fi most of the day and only need maps and messaging in between, three gigabytes is enough.
Is Airalo or Lumbus cheaper for South Korea?
On the fixed sizes, Lumbus, on every row in the table above. The clearest gap is at ten gigabytes for a month, where ours is less than half. At three gigabytes the difference is both price and validity: the comparable plan on the other side runs a week where ours runs a month. On unlimited the gap narrows, and at thirty days the two are within a tenth of each other. Those numbers come from Airalo’s own product page on the date shown above, not from an estimate.
Does a regional Asia eSIM cover South Korea?
Some do and the cheapest one does not. The lowest-priced Asia list covers seven Southeast Asian destinations only: Vietnam, Indonesia, the Philippines, Cambodia, Thailand, Malaysia and Singapore. South Korea is not on it. The Asia lists that include Korea start at twelve destinations, and for a month of ten gigabytes the widest of them costs around five times the South Korea plan. Always read the coverage list, not the region in the name.
Do I need two eSIMs for a Japan and South Korea trip?
Two country plans, one for each, unless you want the single install enough to pay extra for it. At ten gigabytes each they cost around forty per cent less in total than the plan spanning both countries charges for ten gigabytes shared, and you end up with twice the data. Add mainland China and three country plans come to the same money as the three-country plan, for three times the data. Only at the very smallest size does the combined plan come out ahead.
Why does Google Maps not give directions in South Korea?
Korean law restricts the export of detailed national map data, a rule kept in place on national security grounds for close to twenty years, and without that data Google cannot provide turn-by-turn navigation. Search, reviews and pins still work; directions do not. In February 2026 the government granted conditional approval for the data to be exported, but the navigation it would enable has not launched yet. Use Naver Map or Kakao Map, both of which have English interfaces.
Do Naver Map and Kakao Map work offline?
Not in the way Google Maps does elsewhere. Both are built to run with a live connection, and the download-your-maps-before-you-go trick that saves data in other countries does not rescue you in Korea, because the app that offers it is not the app that can navigate. Assume your maps are online all day and buy data accordingly.
Which networks does a South Korea eSIM use?
Ours connects to LG Uplus and SKTelecom, with 5G where available: two of the country’s three national networks. You do not choose between them. The phone scans both and holds the stronger signal, switching by itself as you move. There is nothing to configure after the eSIM is installed.
Is 5G available across South Korea?
Both networks your eSIM uses carry 5G, and coverage in Seoul, Busan and the other cities is dense. Like anywhere, the signal you get depends on where you are standing, how the building is built and how busy the cell is, so treat 5G as what the network offers rather than a guarantee for every minute of your trip.
Should I buy an unlimited eSIM for South Korea?
Only if you tether a laptop most days, you are uploading video, or you value not thinking about it more than the difference in price. Unlimited here gives a full-speed allowance each day and then a reduced speed until it resets, which is true of every provider selling unlimited in Korea. A week of unlimited costs about a quarter more than twenty gigabytes that lasts a month, and a month of unlimited is nearly twice the price of fifty gigabytes over the same period.
Can I buy a SIM card at Incheon Airport instead?
You can, and it costs you a queue at the end of a long flight to get something you could have arranged before leaving home. An eSIM bought in advance installs over your own Wi-Fi and connects by itself when you land, often before you reach immigration. The plan does not start counting down until the eSIM first connects to a Korean network, so buying early costs you nothing.
Will my South Korea eSIM work on Jeju and outside Seoul?
Yes. The plan is national, not city-based, and the two networks it uses cover the country, including Jeju, the KTX corridor to Busan and the smaller cities in between. Signal in the mountains and on quieter stretches of coast behaves the way mobile signal behaves anywhere: mostly fine, occasionally not. Cache anything essential before a long hike.
Can I use my phone as a hotspot for a laptop in Korea?
Yes, tethering works on the fixed plans and on unlimited, and it is the main reason to size up. A laptop pulls far more than a phone, so if you are planning to work from the KTX or a café, take twenty gigabytes rather than ten, or fifty if it is most days for a month. On an unlimited plan a heavy tethering day is the thing most likely to reach the daily full-speed allowance.
What happens if I run out of data in South Korea?
On a fixed plan the data stops and you top up the same eSIM rather than buying a new one, which takes a couple of minutes in your account and does not need a reinstall. On an unlimited plan you never run out mid-day; you drop to the reduced speed until the allowance resets, and if you run out of days you extend the plan while it is still active.
How far in advance should I buy a South Korea eSIM?
Buy it when you book the trip. Every plan we sell has a hundred and eighty day window in which it must make its first connection, so an eSIM bought months ahead simply waits. Install it a day or two before you fly rather than the day you buy: installing does not start the plan, but it does end the fourteen-day cancellation right on uninstalled digital content, so there is no reason to do it early.