Ten plans · five caps · three carriers with none
Unlimited eSIM for South Korea
Every "unlimited" travel eSIM sold for Korea is a daily allowance with a slow lane behind it. The only genuinely uncapped data in the country comes from the Korean carriers themselves, and it costs less. This page puts all of it in one table.
Every figure here is the brand's own published number from its Korea plan page or terms on September 7, 2026. "Not published" means the company would not print the number. We have not run throttle tests in Korea and will not pretend otherwise. If you buy through a link on this page we earn a commission; it never changes your price. How we test.
Every unlimited eSIM cap for Korea in one table published numbers, or the word not
| "Unlimited" plan | Real daily high-speed cap | After the cap |
|---|---|---|
| Saily Unlimited · $18.99 (5 days) to $71.99 (30 days) | 5GB/day | The largest daily allowance among the brands we can link. Saily says speed is reduced for the rest of the day; its blog suggests 1 Mbps or lower, and we have not verified the figure. Six lengths from five to thirty days. Saily does not publish which Korean network it uses. |
| GigSky daily packs · $5.99 (1 day) to $51.49 (15 days) | 3.5GB/day | Not marketed as unlimited: the cap is in the plan name, which is the honest version of the product. The post-cap speed is not printed on the Korea page. Hotspot is included with no separate ceiling. GigSky pays us the highest commission of any brand here, 20 per cent, so weigh that against the recommendation. |
| Airalo Jjang Unlimited · $12.00 (3 days) to $69.00 (30 days) | 3GB/day | Then 1 Mbps until the day resets. Airalo is the only linkable brand that publishes both the allowance and the slow-lane speed, and the only one that publishes its Korean network: SK Telecom, Opensignal's Best Network in Korea for December 2025. One megabit carries Naver Map, KakaoTalk and Papago text; it does not carry video. |
| Nomad Unlimited · $11.00 (3 days) to $33.00 (10 days) · unlinked | 2GB/day | Then 512 kbps according to Nomad's own page (esimdb says 1 Mbps). The smallest cap on this table. Two gigabytes is about two hours of HD video, so this is a messaging plan wearing an unlimited label. We earn nothing from Nomad. |
| Yesim Unlimited · $4.20 (1 day) to $66.20 (30 days) | not published | Yesim states that speed "may be limited in accordance with the network operator's Fair Usage Policy" and gives no figure. Trustpilot reviewers describe a ceiling around 5 Mbps; that is a customer report, not a term. Cheapest thirty days of unlimited we can link, and the only one where you cannot know what you bought before paying. |
| Holafly Unlimited · $12.50 (3 days) to $73.90 (30 days) · unlinked | not published | No gigabyte figure and no throttle speed; Holafly says a fair-usage limit applies "for no more than one day". Hotspot is capped at 1GB a day, which is published. On ${CHECKED} Holafly's Trustpilot profile carried an active banner saying the company is under review for past guideline violations. We earn nothing from Holafly. |
| Ubigi Unlimited · $25.00 (7 days), $34.00 (15 days), $49.00 (30 days) · unlinked | 25GB total per 7 days | A total allowance, not a daily one: 25GB at full speed across the seven days, then 2 Mbps. The 30-day plan is 60GB then 2 Mbps. Printed on Ubigi's own plan pages, on SK Telecom and LG U+. Cheapest week of quasi-unlimited on this page and we earn nothing if you buy it. Full Ubigi review. |
| LG U+ tourist eSIM · ₩27,500 (≈$20) for 5 days · unlinked | none, no speed cap | The carrier's own words: "No Speed Cap, Truly Unlimited", on 5G and LTE. Includes a Korean 010 number. The data-only version arrives by email with no counter visit; the voice version needs your passport at the Incheon, Gimpo or Gimhae counter. Sold in won, so the dollar figure moves with the exchange rate. |
| SKT via krsim.net · $20.70 (7 days, 4G) or $23.20 (5G) · unlinked | none, "no FUP" | SKT's official partner. Unlimited with no fair-use cap, up to 200 Mbps on the 5G plan, 30 days for $42.40. Plans of two days and longer include a 010 number and require passport registration online at krsim after landing, between 08:00 and 22:00 Korean time, or at an SKT airport booth. |
| KT tourist eSIM via resellers · about ₩24,700 (≈$18) for 5 days · unlinked | 3GB/day | Then 5 Mbps, according to a 2026 reseller listing. KT's own eSIM prices are rendered by script and we could not verify them. Passport required. The one carrier plan here with a travel-eSIM-style cap, and even so its slow lane is five times Airalo's. |
Travel-eSIM figures from each brand's published Korea plan details on September 7, 2026, in USD. Carrier figures from lguplus.com, krsim.net and a 2026 KT reseller list on the same date; won converted at roughly ₩1,380 to the dollar and rounded. A daily cap on a travel eSIM resets on a 24-hour or midnight cycle depending on the brand, so a plan activated at 22:00 may hand you two hours of the first day's allowance.
If you want unlimited without a passport queue, buy the largest number anyone will print. Saily's 5GB a day is two thirds more full-speed data than Airalo's 3GB and infinitely more than the two brands that publish nothing. If a queue does not bother you, the carriers beat all of us.
See Saily unlimited plans Or read about the carrier eSIMsWhat unlimited data in Korea costs per day 7, 10, 15 and 30 days
Same table, priced by the day. Blanks mean the brand does not sell that length for Korea.
| Plan | Cap | 7 days | 10 days | 15 days | 30 days |
|---|---|---|---|---|---|
| Saily | 5GB/day | not sold (5d $18.99) | $34.99 · $3.50/day | $48.99 · $3.27/day | $71.99 · $2.40/day |
| Airalo Jjang | 3GB/day, then 1 Mbps | $29.00 · $4.14/day | $35.00 · $3.50/day | $49.00 · $3.27/day | $69.00 · $2.30/day |
| GigSky packs | 3.5GB/day | $27.99 · $4.00/day | not sold | $51.49 · $3.43/day | not sold |
| Yesim | not published | $28.45 · $4.06/day | $34.77 · $3.48/day | $45.29 · $3.02/day | $66.20 · $2.21/day |
| Ubigi · unlinked | 25GB/7d then 2 Mbps | $25.00 · $3.57/day | not sold | $34.00 · $2.27/day | $49.00 · $1.63/day |
| Holafly · unlinked | not published | $27.50 · $3.93/day | $36.50 · $3.65/day | $50.50 · $3.37/day | $73.90 · $2.46/day |
| Nomad · unlinked | 2GB/day | $25.00 · $3.57/day | $33.00 · $3.30/day | not sold | not sold |
| SKT via krsim · unlinked | none | $20.70 · $2.96/day | not listed | not listed | $42.40 · $1.41/day |
| LG U+ · unlinked | none | 5 days ₩27,500 (≈$20) · ≈$4/day | sold, price not captured | sold, price not captured | sold, price not captured |
Two things stand out. Among the plans we can link, the four brands are within fifty cents a day of each other at every length, so the cap is the real difference, and Saily's is the biggest. And SKT through krsim is cheaper than every travel eSIM at seven days and at thirty, with no cap at all. The price of that is a passport registration and a KYC window that closes at 22:00.
Holafly's row is here for completeness: the same money buys Saily with a published cap, or a Korean carrier with none. Prices checked September 7, 2026.
What 3GB, 3.5GB and 5GB a day are in hours gigabytes are not a unit anyone thinks in
Rough conversions using published per-app estimates from a September 2026 usage guide, not our own measurements. HD video at roughly 700MB to 1GB an hour, video calls at about 600MB an hour, Naver Map at 5 to 12MB an hour, a tethered laptop on a working day at 2 to 3GB.
| Daily cap | HD video | Video calls home | Naver Map and KakaoTalk | Laptop hotspot |
|---|---|---|---|---|
| 3GB · Airalo | ≈3 to 4 hours | ≈5 hours | days, not hours | one light working day, then the slow lane |
| 3.5GB · GigSky | ≈3.5 to 5 hours | ≈6 hours | days, not hours | one working day, tightly |
| 5GB · Saily | ≈5 to 7 hours | ≈8 hours | days, not hours | one working day plus the phone beside it |
| 2GB · Nomad | ≈2 to 3 hours | ≈3 hours | days, not hours | half a working day |
Read honestly, the table says something awkward about the whole category. A normal sightseeing day in Korea, maps, KakaoTalk, Papago, photos and an hour of Instagram, runs 500MB to about 2GB. Every cap here covers it. The caps only bite on the two things people actually buy unlimited for: streaming video for hours, and tethering a laptop. On a 3GB cap, a single afternoon of either puts you at 1 Mbps until tomorrow.
Streaming on the KTX is a cap question and a signal question the official rail numbers
The picture on the hero of this page is the fantasy: Seoul to Busan in two and a half hours, a series on the phone, fields going past. Two things decide whether it happens.
The first is the cap, and the table above handles it: two and a half hours of HD video is roughly 2 to 2.5GB, which is most of an Airalo day and half a Saily day.
The second is the signal, and here Korea's own regulator is unusually candid. The Ministry of Science and ICT's 2025 quality evaluation, published December 30, 2025, measured 5G at 974 Mbps on average nationwide and 617 Mbps in rural areas, but only 393 Mbps on high-speed rail, and just 81 per cent of rail measurements cleared the threshold the ministry uses for HD streaming, against roughly 98 per cent everywhere else. Nineteen of the country's 32 weak-5G zones are rail sections. The government has a shared-network plan to fix this by 2027.
So: on the KTX you will stream most of the way, buffer through a fifth of it, and lose the picture in the long tunnels south of Daejeon whatever eSIM you hold. This is the one place in Korea where which network you ride shows up in daily life, and even there the honest advice is to download the episode on hotel wifi.
When a fixed bucket beats every unlimited eSIM for Korea most trips
Unless you stream video daily or tether a laptop for work, a bucket is cheaper and there is nothing to think about. The data page works out which size.
The cases where unlimited genuinely earns its price:
Remote work. A tethered laptop with calls burns 2 to 3GB a day on its own. Over a month that is 60 to 90GB, and the largest bucket we can link is 50GB. Saily's 30 days at $71.99 with 5GB a day is the linkable answer; SKT via krsim at $42.40 with no cap is the cheaper one if you will do the registration.
Short and heavy. Five days in Seoul, hotspotting a tablet for the kids every evening. Airalo's five days at $20.00 with 3GB a day, on SK Telecom, is $4 a day for a ceiling you will actually reach.
Not wanting to think about it. If a data counter would sit on your holiday like a small grey cloud, paying $20 to never open it is a rational purchase, and we will not talk you out of it.
Which unlimited eSIM to buy for Korea if you have decided you want one
| If you are | Buy | Because | The catch |
|---|---|---|---|
| A heavy user who wants a link, a refund policy and no queue | Saily unlimited, 10 days $34.99 | 5GB a day is the biggest published cap we can sell; Trustpilot 4.7 across 30,662 reviews, the best record on this site. | Saily publishes neither its Korean network nor the throttled speed after 5GB. Every Saily price here is from esimdb, because Saily's own Korea page would not load for us on September 7, 2026. |
| Someone who wants to know both numbers and the network | Airalo Jjang unlimited, 5 days $20.00 | 3GB a day then 1 Mbps, both printed, on SK Telecom, the only network any linkable brand names for Korea. | The cap is 60 per cent of Saily's for about the same money per day. Airalo pays us the lowest rate of anyone here, which is not why we rank it. |
| Someone who would rather see the cap in the plan name | GigSky 3.5GB/day, 7 days $27.99 | Honest labelling, hotspot included, and a free 100MB trial to check the network before paying. | Nothing longer than 15 days, no published Korean network, post-cap speed not printed. GigSky pays us 20 per cent, the most of any brand here. |
| Willing to register a passport for real unlimited | SKT via krsim (unlinked), 7 days $20.70 | No cap, a 010 number that passes Korean SMS checks, and it costs less than any travel eSIM above. | Registration online between 08:00 and 22:00 KST after landing, or at an SKT booth. The carrier page has the whole procedure. |
The one we cannot sell: Ubigi's seven days at $25.00 gives you 25GB at full speed on SK Telecom and LG U+, which is more than Airalo's 21GB over the same week, for $4 less. If a total allowance suits you better than a daily one, look there; we earn nothing from it.
For the visitor who will not queue: Saily, because 5GB is the largest number anyone we link will put in writing. For everyone else, the number to look at is the bucket you would actually use.
See Saily unlimited Read the Saily Korea reviewUnlimited Korea eSIM questions short answers
Is there a truly unlimited eSIM for South Korea?
Yes, but only from the Korean carriers. LG U+ sells a tourist eSIM with no speed cap for ₩27,500 (≈$20) over five days, and SKT through krsim sells seven days with no fair-use policy for $20.70. Both need passport registration after landing. Every travel eSIM brand, Saily, Airalo, GigSky, Nomad, Yesim, Holafly and Ubigi, applies a cap. Checked September 7, 2026.
Which unlimited Korea eSIM has the biggest daily cap?
Among brands we can link, Saily at 5GB a day, from $18.99 for five days to $71.99 for thirty. GigSky's packs allow 3.5GB, Airalo 3GB then 1 Mbps, Nomad 2GB. Ubigi works differently, 25GB in total across a seven-day plan then 2 Mbps. Yesim and Holafly publish no figure.
Is an unlimited eSIM worth it for Korea?
Only above about 1.7GB a day over a month, or 1.3GB a day over two weeks, which is where Saily's unlimited overtakes Airalo's 50GB and 20GB buckets. A normal sightseeing day is 500MB to 2GB. Unlimited pays for remote work, daily streaming and hotspotting a laptop, and for peace of mind if you value it at about $20.
What happens after the daily cap on a Korea eSIM?
Speed drops for the rest of that day and comes back when the daily window resets. Airalo publishes 1 Mbps, Nomad 512 kbps, Ubigi 2 Mbps after its 25GB total. Saily says only that speed is reduced. GigSky, Yesim and Holafly do not publish the speed. One megabit still runs Naver Map, KakaoTalk and Papago text; it does not run video.
Can I hotspot on an unlimited Korea eSIM?
On Saily, Airalo, GigSky and Yesim, yes, with no separate hotspot limit, so the daily cap is shared between the phone and the laptop. Holafly limits hotspot to 1GB a day. A laptop on video calls can spend 3GB in one afternoon, so if you tether daily, take the 5GB cap or a carrier eSIM.
Why does streaming on the KTX keep buffering?
Because high-speed rail is the weakest 5G in Korea by the government's own measurement: 393 Mbps average against 974 nationwide, and only 81 per cent of rail readings meet the HD-streaming threshold. Nineteen of 32 weak-5G zones are rail sections. It is not your eSIM; it is the line, and it is the same on all three carriers.
5GB a day, in writing, no passport queue
The largest published daily allowance any brand we link sells for Korea, in six lengths from five days to thirty. If you would happily register a passport for genuinely uncapped data at a lower price, read the carrier page first and buy nothing from us.
See Saily unlimited plansSources & freshness: Caps and prices from each brand's published Korea plan details on September 7, 2026, in USD, before promo codes; Saily figures via esimdb because Saily's Korea page returned a Cloudflare challenge on that date. Carrier data from lguplus.com/korea-sim/eng, krsim.net and a 2026 KT reseller listing; KT's own eSIM prices are unverified. Rail figures from the Ministry of Science and ICT 2025 communications quality evaluation, released December 30, 2025. Hours-of-video conversions use published per-app estimates from a September 2026 guide and are generous to the caps. We have not run throttle tests in Korea. How we test.