Korea is one of the easiest countries in the world to visit without cash. Your Visa works in the corner shop, the taxi, the coffee place, the noodle place with four tables. You can go a whole week without opening your wallet.
Then you walk into a subway station and the system stops recognising you.
That gap is the single most common money problem visitors run into here, and the reason it exists is written down in Seoul's own transport policy. This is what the official sources actually say about money in Korea, and where they go quiet.
Cards first, because that is what you will mostly use
The Korea Tourism Organization puts it plainly. Most businesses in Korea accept credit cards, including major hotels, department stores and general shops, and Visa, Mastercard and American Express all work. The same page adds the obvious caveat that some stores may not.
In practice the exceptions you will meet are small and old: a market stall, a street food cart, a tiny restaurant run by one person, a temple donation box. None of them will surprise you if you are carrying a little cash. Nobody needs to walk around with 300,000 won.
The transit card is the real gap
This is worth being precise about, because a lot of travel advice is ahead of reality.
Seoul is moving to open-loop payment, meaning you would eventually tap your own overseas card straight onto the reader like you do in London or Sydney. The Seoul Metropolitan Government announced the plan in October 2025 and published the timetable. It runs in three steps.
| Step | What happens |
|---|---|
| 2025 – 2026 | EMV modules installed on bus terminals, payment server built |
| 2027 | EMV readers on subway lines 1 to 8 |
| 2028 – 2030 | Town buses, private railways, metropolitan transfers |
Read the middle row again. The subway does not get EMV readers until 2027. So if you are here in 2026, tapping your own card at a subway gate is not a thing yet, whatever a listicle told you.
The city is blunt about the current state in the same announcement. Travelers, it says, must still purchase and reload their transit cards with cash, with no option to pay using overseas credit cards. That is Seoul describing its own system, not a tourist complaining.
So bring some cash, and here is roughly how much
A T-money card costs 3,000 to 5,000 won and you buy it at any convenience store, GS25, CU or 7-ELEVEN, or at a Seoul subway station. You then load it at a ticket machine, up to 500,000 won at a time, which is far more than anyone needs.
Put 20,000 or 30,000 won on it and top up when it runs low. If you end up with a large balance, note that refunds above 50,000 won have to be processed at Tmoney Town near exit 10 of Seoul Station, which is a trip you would rather not make.
There are alternatives. EZL cards start at 4,000 won, but convenience stores will only refund balances under 20,000 won. WOWPASS costs 5,000 won and its kiosks give the remaining balance back as cash. The Climate Card, Seoul's unlimited pass, is 3,000 won for the physical card plus 5,000 won for a one-day pass up to 20,000 won for seven days, and it is worth knowing that the Climate Card can only be bought with cash or a Korean-issued card, which puts you back where you started. There is also Mpass, foreigner-only, 15,000 to 64,500 won for one to seven days, capped at 20 rides a day.
I compared the Climate Card and Mpass in detail separately, so I will not repeat that here.
Getting won in the first place
Korean notes come in 50,000, 10,000, 5,000 and 1,000 won. Coins are 500, 100, 50 and 10 won. The 50,000 note is the largest, which surprises people expecting something bigger given the number of zeroes.
The tourism board's instruction for exchanging money is to go to a bank or an authorized exchange service center. Banks generally open 09:00 to 16:00 on weekdays, with Korea Post Bank running to 16:30, though hours vary by branch.
One warning worth repeating from the same official page: older versions of Korean banknotes may not be accepted at some locations, so if someone hands you a note that looks unusual, check it before you rely on it.
The rule that catches people carrying real money
If you are bringing in a normal holiday amount, none of this applies to you. Korea Customs is clear that means of payment not exceeding USD 10,000 need no permission and no declaration.
Above that line it changes, and the detail that matters is not the declaration itself.
You declare by ticking item 3 on the Traveler Declaration Form, writing the amount, handing it to a customs officer, and receiving the Certificate of Foreign Currency Declaration. Then comes the sentence people miss:
The Certificate of Foreign Currency Declaration cannot be issued after entering Korea (after leaving the immigration)
You cannot go back for it. And on the way out, a non-resident leaving with foreign means of payment within the amount carried at their most recent arrival does not need to report it, but that works because there is a record of what came in. Without the certificate, that record is the thing you do not have.
The penalty for moving means of payment without filing a report is imprisonment with labour of not more than one year, or a fine not exceeding one hundred million won, and the fine is capped at three times the value of the money involved. The legal basis is article 17 of the Foreign Exchange Transactions Act. Customs states the purpose openly: the reporting exists to crack down on drug funds and money laundering.
Korean-won cashier's checks count toward the same threshold, which is easy to forget.
What I could not confirm, and would not guess at
The question everyone actually asks is which foreign cards work in which Korean ATMs. I could not find an official source for that, and I am not going to repeat what other blogs assert, because the answer depends on your issuing bank, the network on the back of your card and the individual machine.
What I would do instead: test one withdrawal at the airport before you leave the arrivals hall, while you still have the option of exchanging cash at a counter. If the card works there, you have your answer for the trip. If it does not, you have found out at the only point where fixing it is easy.
I also could not confirm current ATM fees or withdrawal limits, exchange rates and commissions, or whether the Apple Pay version of Tmoney is live yet. Seoul's announcement describes it as part of the plan, which is not the same as saying you can use it today.
If you are landing soon, the practical order is: clear immigration, get some cash, buy a transit card, then work out how you are getting from Incheon into the city. The transit card comes first because the train needs it. If you are deciding between passes, I wrote up the Climate Card and Mpass comparison separately, and if you plan to spend real money on shopping, the tax refund rules have three limits that decide whether you get anything back.
Sources
- Korea Customs Service, Declaration of Foreign Currency, arrival and departure procedures and penalties
- Seoul Metropolitan Government, Seoul Implements Open-Loop Payments for International Tourists, published 24 October 2025
- Korea Tourism Organization, Korean Currency and Exchange Info
- Korea Tourism Organization, Transportation Cards
All checked on 12 August 2026. Fees, card prices and rollout dates change, so confirm anything time-sensitive before you travel.
