← Part of the South Korea money guide
South Koreachecked Aug 2026StraightforwardStaying connected in South Korea.
Korea has close to the best mobile coverage in the world and free wifi almost everywhere, so there is nothing to plan around. This is a pure cost question, and unusually for Asia the local unlimited SIM is the expensive option.
At a glance
Coverage
Among the best anywhere
Carrier roaming
$10 to $12 a day
Local unlimited
About $25 to $40
Cheapest
An eSIM, unless you use a lot
Coverage is among the best anywhere: fast 5G across the cities, working signal deep in the Seoul subway, on the KTX at speed, in the tunnels and across most of the countryside and the islands. Free wifi is close to ubiquitous in cafes, stations, subway cars and public spaces. So this is purely cost. A local tourist SIM or eSIM from KT, SK Telecom or LG U+ is roughly 25 to 40 dollars for unlimited data over 5 to 30 days, bought with your passport at Incheon or online; that is expensive by Asian standards. A Nomad eSIM at a few dollars per gigabyte is usually cheaper for normal use, and the local unlimited plan only wins if you are a heavy user or want a Korean number. Your US carrier's day pass is about 10 to 12 dollars a day (AT&T and Verizon), though AT&T caps its Day Pass at 10 daily fees per line per bill period, about 120 dollars, while Verizon's TravelPass has no equivalent cap and keeps billing daily. T-Mobile's current tiers include roughly 5GB on Experience More, Magenta MAX and Go5G Plus, 15GB on Experience Beyond and Go5G Next and 30GB on Better Value, slowing to 256kbps after that. Never roam pay-per-use, at about 2 dollars a megabyte.
Coverage you can genuinely ignore
This section is short because Korea has solved it more thoroughly than almost anywhere. You will have fast 5G in Seoul, Busan and the other cities, a working connection deep in the subway and in the tunnels, signal on the KTX at full speed, and good coverage across the countryside, up the mountains around Seoraksan and on Jeju. Free wifi is everywhere, including in subway carriages and most cafes.
The practical consequence is that nobody needs to research networks here the way they would in Indonesia or Namibia. Any option you buy will work. That makes the decision purely financial, which is the situation we would rather be honest in than dress up.
The local unlimited plan is the expensive one
Korea inverts the pattern from most of our Asia pages. A KT, SK Telecom or LG U+ tourist plan runs about 25 to 40 dollars for unlimited data over 5 to 30 days, sold at Incheon arrivals and bookable online for pickup. That is a lot next to the 5 dollars that buys a month in Vietnam, and it reflects a high-cost domestic market rather than a tourist markup.
Against that, a Nomad eSIM at a few dollars per gigabyte covers a normal week for less, and we should be clear that we earn on that, so here is the check: the local plan wins if you will genuinely use a lot of data, tethering or streaming daily, since unlimited is unlimited, or if you want a Korean number, which is worth more here than in most countries because some domestic apps, delivery services and reservation systems want one. For maps, messaging, translation and photos, the eSIM is the cheaper answer.
Roaming, and what your plan may already cover
Check your own plan before buying anything, because Korea is a country where a T-Mobile customer may need nothing: T-Mobile's current tiers include roughly 5GB on Experience More, Magenta MAX and Go5G Plus, 15GB on Experience Beyond and Go5G Next and 30GB on Better Value, slowing to 256kbps after, and on a week in Seoul with wifi everywhere, 5GB goes a long way. Verizon's Unlimited Ultimate tier includes international data outright, so a Verizon customer should look too.
Otherwise AT&T and Verizon day passes are about 10 to 12 dollars a day, so 70 to 84 dollars a week, and AT&T caps its Day Pass at 10 daily fees per line per bill period, about 120 dollars, while Verizon's TravelPass has no equivalent cap and keeps billing daily. Do not roam with no plan, since pay-per-use is about 2 dollars a megabyte. This guide is written for US travelers departing the US. For more, see cash or card in South Korea, taxis and apps in South Korea, and the South Korea money guide.
Common questions
Quick answers.
Do I need an eSIM for South Korea?
Coverage is not the issue, so it is purely cost. A travel eSIM at a few dollars per gigabyte is usually cheaper than a Korean tourist plan at 25 to 40 dollars for unlimited data. Check your own US plan first: a T-Mobile mid or upper tier includes 5GB to 30GB abroad, and Verizon's Unlimited Ultimate includes international data outright.
Why are Korean tourist SIMs expensive?
It reflects a high-cost domestic mobile market rather than a tourist markup. Unlimited plans from KT, SK Telecom and LG U+ run about 25 to 40 dollars for 5 to 30 days, which is well above the Asian norm. They are worth it for heavy users, or if you want a Korean number for domestic apps and reservations.
Is there free wifi in South Korea?
Yes, close to ubiquitous, including in cafes, stations, public spaces and subway carriages. Combined with coverage that is among the best anywhere, that means a light user can get by on very little data.
How much does it cost to use my US phone in South Korea?
About 10 to 12 dollars a day on an AT&T or Verizon day pass, so roughly 70 to 84 dollars a week. AT&T caps its Day Pass at 10 daily fees per line per bill period, so about 120 dollars covers the rest of that bill period on land, while Verizon's TravelPass has no equivalent cap and keeps billing daily. T-Mobile is worth checking first, since its mid and upper tiers include 5GB to 30GB of high-speed data abroad, which with Korea's ubiquitous wifi may be all you need.
More on South Korea
The little money things nobody warns you about.
- Taxis in South Korea, and the Kakao T appKorean taxis are cheap, honest and metered, and the Kakao T app makes hailing one effortless even with no Korean. From Incheon the train usually wins, and you never tip. Here is how it works.
- Tipping in South KoreaSouth Korea is not a tipping country. At restaurants, cafes and in taxis, no tip is expected, and trying to leave one may be politely refused. Here is what you actually owe.
- Do US citizens need a K-ETA for South Korea?Short answer: not right now. For US travelers the K-ETA is waived through the end of 2026, but there is a free arrival card you still must file, and the K-ETA comes back in 2027. Here is what you actually need, and when.
- Do I need cash in South Korea, or can I use cards?Short answer: mostly cards, a little cash. Korea runs on plastic, so a Visa or Mastercard covers almost everything, but markets and street food still want won. Here is how to pay, get around, and which apps to skip.
- Bringing your dog or cat to South Korea.South Korea is the most straightforward of the strict-looking Asian destinations. There is no import permit to chase for a personal pet, and a dog or cat that meets the microchip and rabies-titer rules is typically released the same day it lands. The one thing that sets your timeline, and that you must not skip, is the rabies antibody titer. Here is the route.
- What does getting sick in South Korea cost a visitor?South Korea is one of the easier countries in Asia to be unwell in. Care is fast, modern and widely available, and the only real complication is that none of the national insurance is yours.
Sources, and how this was checked
Last checkedAug 2026
- T-Mobileinternational roaming pages listing the high-speed data allowance by plan tier
- Verizoninternational travel pages, the TravelPass daily rate and what it includes
- AT&TInternational Day Pass details, the daily rate and the 10-fee cap per bill period
- KTprepaid tourist SIM and eSIM plan pages
- US State DepartmentSouth Korea country information for US travelers
Our own readChecked Aug 2026. Korea is the Asian country where our usual advice inverts, and saying so matters because a reader arriving from our Vietnam or Cambodia pages would reasonably expect the local SIM to be the cheap option and it is not. The honest first move here is checking your existing US plan, since coverage plus ubiquitous wifi means a modest included allowance goes further in Korea than almost anywhere. Local plan pricing is a current read in won and varies by duration and outlet.
How we checkHow every guide is researched, checked and dated