Every crossing has a second, invisible bill: the cost of turning one currency into another and getting it accepted on the other side. Between Korea and Japan that bill is unusually easy to measure, because both countries price the same journey very differently depending on which way you go.
Four places your money is repriced
There is no single "exchange fee". There are four separate charges, and most travellers notice only the first.
| Where the money leaves | What it looks like | Typical size | Who avoids it |
|---|---|---|---|
| Cash rate spread | A counter's rate against the mid-market rate | 1.5% to 4% of cash | Anyone who compares two counters, or skips cash |
| Card foreign-transaction fee | A line on your statement after you get home | 0% to 2% of card spend | Cards that charge no FX fee |
| Dynamic currency conversion | "Pay in your home currency?" at a terminal or ATM | 3% to 6% of that transaction | Anyone who taps local currency |
| Unclaimed consumption tax | Tax left at the till or at the airport | 8% to 10% of eligible goods | Shoppers who keep receipts and leave time |
The ranges above are what the market quoted in late 2026; your own bank's schedule is the only one that applies to you. The point is not the exact numbers — it is that three of the four are invisible until you look for them.
Direction one: leaving Korea for Japan
Buy yen where yen is a stocked product
In Korea, the yen is a major retail currency. Bank branches, airport counters and the private exchange offices clustered around tourist districts all hold it, and their spreads sit roughly between 1.5% and 3%. The airport is the most convenient and rarely the cheapest; a bank app ordered a day ahead usually beats the departures-hall counter.
The better move is not to buy cash at all. A card with no foreign-transaction fee settles at the card network's rate, which in practice lands within about 1% of mid-market — cheaper than almost any cash counter. Buy cash only for the places that will not take a card.
At the terminal, the answer is always yen
Japanese terminals increasingly ask whether you want to be charged in won. That question is not a courtesy; it is a product. The terminal sets its own rate and adds a margin of roughly 3% to 6%, and the margin is invisible because your receipt shows a won amount that looks final. Say no. Choose yen, let your bank convert at its rate, and check the statement later.
Japan still runs on cash at the edges
Convenience stores, chain restaurants, hotels and department stores take cards almost everywhere. Small izakaya, shrines, rural buses, some taxis and market stalls do not. A float of ¥10,000 to ¥20,000 for a week covers the gaps without turning you into a walking cash machine.
The refund rule changed this month
Until 31 October 2026, tax-free shops in Japan simply sold to foreign visitors at tax-exclusive prices. From 1 November 2026 the country moved to a refund method: you pay the tax-inclusive price at the shop, and the consumption tax — 10% standard, 8% on food and some other items — is refunded after customs confirms at departure that the goods are leaving the country.
The mechanics decide whether you actually get the money:
- Purchases of ¥5,000 or more before tax, per store, per day, are eligible. Receipts are not combined across shops.
- The procedure must be completed within 90 days of purchase, before security and before you check your bags — the goods have to be with you.
- Present your passport at a tax-free kiosk, or use Visit Japan Web on the dedicated airport Wi-Fi, in the international departure lobby. The terminal returns a green result (nothing more to do) or a red one (take the goods to a customs officer).
- Each receipt is inspected separately. If one item from a receipt is missing, that entire receipt loses the refund.
- Consumables — food, drinks, cosmetics — are no longer sealed in special packaging, but anything you consume in Japan becomes ineligible.
- The refund is paid by the retailer after customs confirmation, usually to a card or payment app, not necessarily as cash at the airport.
That last point is the one that catches people: a refund you never collect is not a refund. Nineteen receipts in a wallet are worth nothing at the gate.
Direction two: arriving in Korea from Japan
Do not buy won in Japan
The won is a minor currency at Japanese bank counters: thin stock, wide spreads, limited hours. The liquidity is in Korea. Change yen at a Korean bank or a licensed exchange counter — or, better, land and use a card and a Korean ATM. For a Japanese visitor, the exchange counter is a fallback, not a plan.
Korea takes the tax off at the register
Korea runs the opposite system. Show your passport at a participating shop and the value-added tax is deducted from the price you pay, within these limits:
- ₩15,000 or more per receipt, tax included — two ₩9,000 purchases do not add up to one eligible ₩18,000 one.
- Under ₩1,000,000 per transaction for an instant refund.
- Up to ₩5,000,000 in instant refunds across one trip.
- Bigger receipts still qualify for a refund at a downtown counter (up to ₩6,000,000 per purchase, with a card held as guarantee) or at the airport after a customs check.
- Goods must leave Korea within three months of purchase, unused.
Korea's VAT is 10%, which is one eleventh of a tax-included price: on a ₩110,000 receipt the tax is ₩10,000, and the licensed refund operator keeps part of it. The refund is for visitors staying under six months who are not working in Korea, so a working-holiday visa changes the maths.
Cards work almost everywhere; carry a little cash anyway
Korea is close to cashless: cards and transit cards cover taxis, markets, cafés and most stalls. A T-money card for the subway and bus removes the main reason to hold coins. Keep ₩50,000 or so for the exceptions — some traditional markets, small stalls, a few rural buses.
Which ATM to use
Korean bank and convenience-store ATMs generally accept foreign cards, with an operator fee of a few thousand won per withdrawal; the screen tells you before you confirm. Choose won, decline any conversion offer, and withdraw in one pull rather than four — the fixed fee does not shrink with the amount.
The asymmetry, on one page
The two directions are not mirror images. The same line item is priced differently because the currency, the refund system and the cash culture all differ.
| Korea → Japan | Japan → Korea | |
|---|---|---|
| Cash you actually need | A real float — small restaurants, shrines, rural transport | Very little — cards and transit cards cover most of it |
| Where the rate is competitive | Korea: the yen is a stocked retail currency here | Korea again: won liquidity sits in Seoul, not in Japan |
| When the tax comes back | At the airport, after a customs check, before check-in | At the register, immediately |
| Refund minimum | ¥5,000 before tax, per store per day | ₩15,000 including tax, per receipt |
| Refund ceiling | No stated ceiling; goods out within 90 days | ₩1,000,000 instant per receipt, ₩5,000,000 per trip |
| The expensive default | Airport kiosk plus a "won?" prompt at the till | Buying won at a Japanese bank counter |
Cash you actually need
Korea → Japan
A real float — small restaurants, shrines, rural transport
Japan → Korea
Very little — cards and transit cards cover most of it
Where the rate is competitive
Korea → Japan
Korea: the yen is a stocked retail currency here
Japan → Korea
Korea again: won liquidity sits in Seoul, not in Japan
When the tax comes back
Korea → Japan
At the airport, after a customs check, before check-in
Japan → Korea
At the register, immediately
Refund minimum
Korea → Japan
¥5,000 before tax, per store per day
Japan → Korea
₩15,000 including tax, per receipt
Refund ceiling
Korea → Japan
No stated ceiling; goods out within 90 days
Japan → Korea
₩1,000,000 instant per receipt, ₩5,000,000 per trip
The expensive default
Korea → Japan
Airport kiosk plus a "won?" prompt at the till
Japan → Korea
Buying won at a Japanese bank counter
Both columns describe the same 900-kilometre corridor. The difference is not distance; it is which side holds the liquidity and which side refunds at the till.
A worked example: ₩1,000,000, two ways
Assume 100 yen = 900 won, a 3% kiosk spread, a 1.5% card fee, a 4% conversion markup, ¥220 per ATM withdrawal, and a refund operator that keeps 10% of the tax. The arithmetic scales if your numbers differ.
| Line | The default path | The deliberate path |
|---|---|---|
| ₩300,000 changed at an airport kiosk (3%) | ₩9,000 | — |
| ₩400,000 spent on a card with a 1.5% fee | ₩6,000 | — |
| One "pay in won" accepted on ₩150,000 (4%) | ₩6,000 | — |
| ATM operator fees, three pulls versus one | ₩5,940 | ₩1,980 |
| Consumption tax on ₩200,000 of goods | ₩18,182 left behind | ₩16,364 refunded |
| Net cost of moving the money | about ₩45,100 (4.5%) | a gain of about ₩14,400 |
The deliberate path comes out ahead only because the refund is money you already handed over at the till. It is not a discount; it is your own tax coming back. Strip the refund out of both columns and the difference is still ₩26,900 — a quarter of which is a single click at a terminal.
What to do before you leave
- Check what your card charges abroad, and carry a second card on a different network. A refused card in a Japanese train station is a bad time to discover a single point of failure.
- Know your PIN. Contactless-only habits fail at ATMs, and some machines will not accept a card without one.
- Raise your daily withdrawal limit before you fly, so one pull can cover the week.
- Photograph every tax-free receipt and keep those goods in your carry-on. A refund you cannot show is a refund you will not get.
- Arrive at the airport early enough for the kiosk queue, and do the tax-free procedure before bag drop, not after.
- Never accept a terminal's offer to charge you in your home currency. In either country, the answer is the local one.
The rule underneath all of it
The rate on the screen is a price, not a fact. Two counters two hundred metres apart quote different prices for the same yen, and the gap between them is the product being sold. Once you start reading the four charges as separate line items, the cheapest route stops being a secret and becomes a routine.