Sending money to Japan and South Korea: big numbers, floating currencies, careful banks

Send a thousand dollars to Japan and the recipient’s statement shows something like 150,000. Send the same to Korea and it shows more than a million. Nothing’s wrong. Both currencies are simply denominated in small units, so the numbers look dramatic.

That visual shock is the first thing to understand about these two corridors, and it causes more practical trouble than you’d expect. The rest is about how two wealthy, well-regulated economies handle incoming money, and which bits of that you can verify before you send.

Two floating currencies with different histories

The yen has floated since early 1973, according to the Bank of Japan (its own page says February; the Ministry of Finance’s chronology says March). Japan’s Ministry of Finance holds the legal power to intervene, with the Bank of Japan acting as its agent, and it has stepped in at times to slow sharp moves. There’s no peg. Our guide on why the yen behaves the way it does goes into the reasons.

The Korean won has a shorter free-floating record. The Bank of Korea says daily fluctuation limits on the interbank rate were abolished in December 1997, during the Asian financial crisis, making the won free-floating. Before that it had moved from a fixed rate to a basket peg (1980) and then to a market-based system with a daily band (1990), a band that was widened step by step.

For a sender, the practical meaning is the same for both. No central bank is promising a particular rate, so any quote you see is only good for a short time. The guide on pegged vs floating currencies sets out what that means. And if you want to see how the numbers look right now, USD to JPY and USD to KRW show the current mid-market figures, refreshed hourly.

Nobody can tell you which way either currency goes next, and this guide won’t try. What you can do is shrink the part you control. Send when you need to, avoid a rushed send on a day you’ve seen a spike, and compare the rate you’re offered with the mid-market figure at the same moment, as laid out in the mid-market rate vs the rate you actually get.

The zero-decimal problem

Here’s the quirky part. In practice the yen has no subdivision: the old sub-units, the sen and the rin, were withdrawn from use in the 1950s, so prices and bank balances are in whole yen. The won is much the same in everyday life: its smallest coins are rarely seen and banknotes run up to 50,000 won.

That makes the arithmetic look scary and makes typing mistakes easy. A bank clerk or an online form won’t flinch at 1,500,000. You might, if you meant 150,000.

One small side effect: providers round the delivered amount to whole yen or won, so the last digit never matters. It’s the margin and the fees that decide what lands, not the rounding. Think of it like a currency counter that only deals in big notes; the small change was never going to move the total.

Worked example one: the margin

All illustrative. Say the mid-market rate is 150 yen to the dollar. You send $1,000. At the mid-market rate that would be ¥150,000. A provider that adds a 1% margin delivers ¥148,500, so ¥1,500 has quietly gone, which is exactly $10 at that rate. Not painful, but it’s on a thousand dollars; scale it to $10,000 and it’s $100.

For Korea, say 1,400 won to the dollar (also made up). $1,000 converts to ₩1,400,000 at the mid-market rate. A 2% margin leaves ₩1,372,000, a shortfall of ₩28,000, or $20. The gap looks big in won and small in dollars, which is exactly why you convert the shortfall back to your own currency before judging a quote. The guide on how to spot a bad transfer deal gives a checklist.

Worked example two: the decimal slip

Now the typing risk. Suppose you mean to send an amount that converts to ¥150,000 and your finger slips so the recipient-side amount reads ¥1,500,000. At 150 yen to the dollar, that is $10,000 instead of $1,000. Many apps ask you to enter the amount in your own currency, which protects you. Some let you set the amount the recipient receives. Either way, the confirmation screen is the moment to read the figure slowly, digit by digit, and compare it with what you meant.

Cash is regulated in both countries

It’s tempting to think of Japan, with its reputation for cash, as relaxed about banknotes. It isn’t relaxed about moving them across a border. Japan Customs says that if you carry cash or other means of payment worth more than one million yen into or out of the country, you must declare it. That includes foreign currency, cheques and traveller’s cheques, promissory notes and securities.

Korea’s customs service sets a threshold in dollars instead. Travellers carrying foreign currency, won notes or cashier’s cheques worth more than US$10,000 must report them to customs when arriving, and the declaration certificate can’t be issued once you’ve passed through immigration. Under the Act cited by the customs service, violators face up to one year in prison or a fine of up to 100 million won (higher in some cases).

Country	Cash declaration level	Equivalent at 150 yen per dollar (illustrative)
Japan	More than ¥1 million	About $6,667
South Korea	More than US$10,000 (arrivals)	$10,000

Because Japan’s threshold is set in yen, its dollar value moves with the exchange rate. The yen threshold stays put; the dollar equivalent doesn’t. Neither is a reason to avoid cash entirely for a small trip, since most people never come close. But if you’re moving serious money, a bank transfer leaves a clean paper trail and removes the border problem. The guide on sending money safely covers the wider reasons to avoid carrying or posting cash.

What a bank looks for on arrival

Exact reporting thresholds for incoming bank transfers differ by institution and change over time, so none are quoted here. What can be said is how the process usually looks from the receiving end, in general terms.

A bank that receives an international payment matches three things: the account number, the beneficiary’s name and the details of who sent it. If those don’t line up, the payment stops for a manual check. In these two countries, names are often held in a form that doesn’t match how a foreign sender types them, because Latin-letter spellings of Japanese and Korean names have several versions. Ask the recipient for the name exactly as it appears on their bank documents, and copy it, rather than guessing the usual spelling.

Larger transfers can also trigger questions about purpose. A plausible reason and a document (a tuition invoice, a rental contract, a sale agreement) usually settles it. Have the paperwork ready before you press send. That’s the same logic explained in the guide on transfer limits and why they exist.

Timing across time zones

Japan and Korea both sit at UTC+9, which puts them well ahead of London and New York. A transfer you send on a Friday afternoon in New York or London arrives in a country that’s already well into Saturday. Local settlement happens on local business days, and both countries have long public holidays when banks close, such as Japan’s Golden Week or Korea’s Lunar New Year and Chuseok. Check dates for the year you’re sending in. If you have a deadline, such as rent or tuition, send a few days early. See how long international transfers take.

A short pre-send routine

Compare quotes by “recipient gets”, in yen or won, at the same minute.
Convert the difference back into your own currency to judge it.
Get the recipient’s bank details and name spelling from their bank paperwork.
Read the amount on the confirmation screen digit by digit.
Keep a document that explains the purpose of any large payment.

If you’re sending to a student, the guide on paying tuition, rent and living costs from abroad pairs well with this one. As always, this is general information, not financial or legal advice; confirm current rules with your provider and the receiving bank.

Sources

Checked: November 2026