eSIM for South Korea: The Number Visitors Cannot Buy

Korea sells the cheapest entry plan in this pair of markets and the least usable phone number. One gigabyte costs $1.00 and a month of 20GB costs $14.00, the networks are fast and the coverage is national, and none of that opens a Korean bank account or gets dinner delivered to an apartment.

The blocking step is not the connection. It is a check that runs against the line behind it, and a data profile has no line to check. That single fact rearranges the whole purchase, which is why the prices come first on this page and the number comes third.

Why the Korean price ladder runs backwards

Ten brands sell 185 Korea plans between them. 99 are flat rate, the cheapest plan is $1.00 and the dearest is $73.90, a 73.9-fold spread. The median metered plan costs $1.47 per gigabyte, which is 2.7 times the market floor and 8 per cent below Japan’s median of $1.60.

The first two columns take the cheapest plan a brand sells at that size, with its validity printed beside the price, and the last column is the highest price anyone pays at that size.

Two rows break the shape a price ladder is supposed to have. At 1GB the market spans $1.00 to $7.00, seven times, which is the widest spread at any size in either country. Jetpac asks $7.00 for a single gigabyte over four days while Roamic asks $1.00 for the same gigabyte over seven.

At 50GB the ladder inverts a second time. Roamic’s 50GB is $29.00 for thirty days, which is $0.58 per gigabyte, and that is cheaper per gigabyte than the $0.70 of its own 30-day 20GB plan. Paying $15.00 more buys 30GB, so the marginal gigabyte at the top costs $0.50 against $0.70 on average in the middle.

The same inversion appears inside single brands. Roami charges $6.99 for 3GB over thirty days and the same $6.99 for 5GB over thirty days, so the two extra gigabytes cost nothing at that window, and it sells 5GB for three days at $4.99, which is cheaper than either. It also sells 30GB for fifteen days at $19.99 while 20GB for thirty days costs $22.99, so the shorter window carries half again the volume for less money. Jetpac repeats the pattern at the top: 30GB for thirty days costs $34.99 while 20GB for thirty days costs $43.00, which is why that $43.00 sits alone in the dearest column.

Which size survives a twelve day trip

The best rate in the Korean file is $0.55 on 20GB, and it belongs to a seven-day plan. A twelve-day trip that buys on cost per gigabyte therefore buys a plan that expires on day seven, and that is the most common mistake in this market rather than an edge case.

The thirty-day version of the same allowance is $14.00 from Roamic, which is $0.70 per gigabyte. The upgrade costs $3.01 and buys 23 extra days plus 27 per cent worse arithmetic per gigabyte. Read as a daily rate the seven-day plan is $1.57 a day and the thirty-day plan is $0.47, so the plan that looks expensive per gigabyte costs under a third as much per day.

The 10GB row has the same trap in a smaller size. Roami’s $6.99 runs three days and Roamic’s $7.00 runs thirty, so one cent buys 27 extra days. The two plans come from different sellers, which is the only reason the trap exists at all: nobody comparing one brand’s ladder sees it.

The order to think in is days first and volume second. A week in Seoul with maps, translation and some video is 5GB to 10GB, and both sizes are available on a 21-day or 30-day window for under $8.00. A fortnight needs the thirty-day column and nothing else.

What a Korean number actually unlocks

Korea verifies identity through the mobile line. A service that needs to know who is using it asks the carrier whether the number is registered to that person, and the answer comes back from records rather than from a form the user fills in. This is why a Korean number is closer to a digital identity than to a contact detail.

The list that stays closed to a data profile is short and specific. Banking apps such as KakaoBank and Toss. Food delivery platforms including Baemin and Coupang Eats. Korean ticketing and reservation systems that run the same check at signup. Ride hailing sits in between, because some accounts have opened on a passport and some have not, which makes it a thing to test rather than a thing to assume.

The list that stays open is longer. Naver Map and KakaoMap, which is what Korea actually uses instead of Google Maps, run on data alone, and so does Papago translation. KakaoTalk works. Card payments work. Subway apps, hotel wifi and every international app a visitor already has are unaffected.

One consequence is easy to miss. A number that cannot pass a check is still worth having for the fifteen minutes after landing, when a guesthouse wants to confirm an arrival time and the airport wifi wants a registration before it hands out a connection. That is an argument for a number at the counter and not for a 1GB plan at $7.00.

So the question to settle before buying is not whether a number would be nice. It is whether anything on the itinerary needs to pass a check, and for a trip built on hotels, restaurants and trains the answer is no.

Three rungs between data and identity

There are three products in this market and they are not variations on each other. Each one buys a different amount of identity, and the price difference between them is small compared with the difference in what they open.

The first rung is a data eSIM. It carries no number, costs from $1.00, installs before the flight and asks for nothing. It is the only rung a short visit can reach in an afternoon.

The second rung is a prepaid line bought on a passport. It has a real Korean number, it receives texts and it can usually place calls after a top-up. It does not pass the identity check, because the check asks whose name the line is in and a passport registration is not the same record as a resident registration.

The third rung is a postpaid contract. It passes every check, and it needs an Alien Registration Card, a Korean payment method in the same name, and time.

What a passport buys at Incheon

A number, and a queue. Both Incheon terminals sell prepaid lines on a passport alone, and Seoul convenience stores match them, and the whole transaction takes minutes once it is someone’s turn.

What that number will not do is the thing most buyers want it for. It is registered to a passport rather than to a resident record, so banks, delivery platforms and the PASS app decline it at the verification step even though the SMS arrives. A traveller who needs a number to receive a call from a guesthouse has bought the right product. A traveller who needs it to order dinner has not.

What the card changes

Everything, and it is slow. Anyone staying more than ninety days must register as a foreign resident within ninety days of entry, through the HiKorea portal and a local immigration office. The physical card commonly takes weeks to arrive, because the wait is an appointment and processing rather than printing.

One detail catches people out. The certificate proving that registration is in progress is not accepted for activation, and only the card is. A postpaid contract then adds a Korean payment method in the same name, which means a Korean bank account or a Korean-issued card. The order for a long stay therefore runs data first, then the card, then the bank, then the contract.

Which eSIMs carry a Korean number

A travel eSIM usually has no number, and that is a product decision rather than a technical limit. The same format can hold a voice line, and two Korean carriers sell exactly that to visitors, which is why the search for a Korea eSIM with a phone number returns something real rather than a dead end.

The two products are built differently. The SK Telecom-based tourist eSIM carries a 010 number that receives calls and texts, and passport registration is required before voice and SMS work. The LG U+ based product carries an 012 number, publishes 3GB a day at full speed before a drop to 5 Mbps, and is sold for unlocked iPhones only.

Both are useful and neither solves the problem this page is about. A 010 number that receives texts is enough for a guesthouse to confirm a booking, for a delivery driver to call, and for an airline to send a gate change. It is not enough for the identity check, because that check reads the registration behind the line rather than the number in front of it, and a passport registration is not a resident registration.

The practical test is the signup screen rather than the plan page. If an app only needs a number to send a code, the 010 product works. If it needs to confirm who is signing up, it will fail on a passport registration and there is no product a visitor can buy that changes the outcome.

Why more than half the shelf is flat rate

99 of the 185 Korean plans are sold flat rate, which is 53.5 per cent, the highest share of the two markets here and higher than Japan’s 48.3 per cent. The cheapest thirty-day flat-rate plan costs $41.00, and the dearest is Holafly at $73.90.

Against a metered 20GB plan at $14.00 for thirty days, the $41.00 entry point costs 2.9 times as much. What it buys is the absence of a volume decision, and in Korea that is worth less than it looks, because hotel, cafe and subway wifi are good enough that streaming happens off the mobile connection rather than on it.

What separates the flat-rate plans is the daily allowance, which the checkout rarely shows. Roamic publishes 3GB a day at full speed before a drop to 1 Mbps, and so do Airalo and Jetpac. Saily publishes 5GB, the most generous figure in the market. Nomad publishes 2GB, alosim between 1.5GB and 2GB before a 512 Kbps drop, and Holafly publishes nothing at all.

The flat-rate ladder itself is steep at the short end. Roamic charges $8.00 for three days, $16.00 for seven and $41.00 for thirty, so a week costs exactly double a long weekend and a month costs 2.6 times a week. A four-day stop pays $2.50 a day and a fortnight pays $1.93, and neither buyer gets more data than the other.

Read that against price and the shelf rearranges itself. Roamic’s 30-day unlimited is $41.00 with 3GB a day, Holafly’s is $73.90 with no published figure and independent testing in early 2026 measuring its cut-off between 500MB and 1GB a day. Paying $73.90 instead of $41.00 buys a lower ceiling rather than a higher one, and the plan that costs more is the one that runs out of full speed sooner.

Ubigi sells no unlimited plan into Korea at all, which is unusual for a brand that owns the Japan market’s searches. Its ten Korean plans run from $3.00 to $49.00 and its best rate is $0.70 per gigabyte, the third best in the file behind Roami’s $0.55 and Roamic’s $0.58.

Where Airalo and Ubigi land in Korea

Airalo sells 18 Korea plans from $4.00 to $69.00 and its best rate is $0.98 per gigabyte. Its 5GB plan for seven days costs $10.00, which is 2.5 times Roamic’s $4.00 for 5GB over 21 days, and its 50GB plan at $49.00 is the dearest 50GB here against $29.00.

Ubigi’s Korean ladder is short and oddly shaped. It has no 5GB plan at all, 10GB for seven days costs $12.00 where Roamic charges $7.00 for thirty, and its only 20GB costs $14.00 for thirty days, which is exactly Roamic’s price for the same allowance. So the brand with the network story matches the budget house at one size and loses at every other.

Yesim holds a record nobody advertises. Its 1GB plan for thirty days costs $2.84, which is the cheapest thirty-day product in the file at $0.09 a day, and per gigabyte it is $2.84, or 5.2 times the market floor. Cheap per day and expensive per gigabyte are the same product read two ways.

Does a Korea plan reach Japan

No. A Korea-only profile names one country, and the forty-minute flight makes the two feel like one trip, which is exactly why the omission surprises people at Gimpo.

A route that continues to Osaka needs either a second profile or a regional product naming both. Two single-country plans are usually cheaper than one bundle, because a bundle is priced against its most expensive country, and the Japan table prices the second leg on its own. The Asia coverage breakdown shows which bundles name both countries rather than one of them. Anyone buying both should read the Japan guide first, because the two markets price the same allowance very differently.

Which handsets fail on Korean networks

Two, and neither is fixed by a better plan. A handset still locked to a home carrier will refuse a Korean profile outright, whatever was paid for it, and the unlock has to be requested from the carrier that sold the phone before leaving. That is the common failure and the cheap one to prevent.

The second is a handset sold in mainland China, where iPhones and most Android models ship without eSIM hardware at all. No profile installs on them and no support ticket changes that. A physical SIM bought at the arrivals counter is the only route, which is one of the few cases where the counter wins.

The compatibility check settles both from a model list in under a minute. It is worth doing before the purchase rather than after, because a profile that was bought and never connected to a network can usually be swapped, while a profile that connected once is a used product.

How the purchase works before Incheon

Buy on the seller’s site, install on home wifi, and leave the line switched off until the aircraft lands. Nothing is collected at the airport and there is no counter conversation, which makes the prepaid desk a choice rather than a step.

At Incheon the order is line on, roaming on for that line, then mobile data pointed at it. Roaming looks wrong and is required, because the profile works by registering on a Korean network. The home line stays live for incoming texts with data roaming off, which is the standard dual SIM arrangement, and the install walkthrough covers the two settings that decide whether the connection comes up on landing.

The counter alternative is worth pricing rather than dismissing. A prepaid line with a number costs more than a data plan and delivers calls and texts that a profile cannot, so it wins for anyone whose trip needs a number and loses for everyone else. The South Korea table sorts all 185 plans by gigabyte price and by day price, and the calculator turns dates into a figure.

What support can and cannot fix

A deleted profile is gone. One QR code carries one install, and once the profile is on the handset the code is spent, so deleting it in settings leaves nothing to scan. Some sellers reissue once through the order page when the profile was never used, and some do not.

Two failures look like seller faults and are not. A carrier-locked handset refuses the profile, and a phone without eSIM hardware cannot accept one. Both are settled before the flight, and both are invisible to a support desk reading an order number.

What the seller can see is whether data moved. A profile bought and never attached to a Korean network is usually swappable inside a short window, and a profile that connected once is not. That is the order to do things in: unlock, check the model, then buy.

Keep the order email until the trip ends. It is the only proof of purchase, and it is what a reissue is checked against.