Carrying cash from United States to South Korea
Two separate rules apply to any cash journey: one where you leave, one where you arrive.
Do you need to declare?
Yes: and on both legs of the journey. Leaving United States, U.S. Customs and Border Protection requires a declaration above USD 10,000. Entering South Korea, Korea Customs Service requires a declaration above USD 10,000. The two rules are independent: satisfying one does not satisfy the other.
Travelling as a family or group?
The threshold applies to your combined total, not per person. A family of four each carrying a little under the limit is still over it, and splitting cash between travellers to stay under does not make it legal.
The two legs
| Leg | Limit | Form | Authority |
|---|---|---|---|
| Leaving United States | USD 10,000 | FinCEN Form 105 (CMIR) | U.S. Customs and Border Protection |
| Entering South Korea | USD 10,000 | Traveler Declaration Form | Korea Customs Service |
The same reporting duty applies when leaving the United States.
Below USD 10,000 in total means of payment, no permission or declaration is needed. Above it, report the amount on the Traveler Declaration Form and keep the Certificate of Foreign Currency Declaration you are given, it is what lets you take the money out again.
If you do not declare
United States: Seizure of the currency and possible civil and criminal penalties.
South Korea: Failure to report is subject to fines or penalties.
There is no limit on how much you may legally carry in either direction, the duty is to report it, not to keep under it. Failing to report is the offence.
Currencies
United States uses USD; South Korea uses KRW.
Sources: rules as of 22 September 2026. This is general information, not legal advice; always check the official authority before travelling.