Carrying cash from United States to United Kingdom
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 United Kingdom, HM Revenue & Customs requires a declaration above GBP 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 United Kingdom | GBP 10,000 | Declare cash online (GOV.UK) or form C9011 | HM Revenue & Customs |
The same reporting duty applies when leaving the United States.
Declare cash of GBP 10,000 or more carried between Great Britain and any other country. Northern Ireland has separate rules.
If you do not declare
United States: Seizure of the currency and possible civil and criminal penalties.
United Kingdom: Cash may be seized and a penalty of up to GBP 5,000 applied.
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; United Kingdom uses GBP.
Sources: rules as of 22 September 2026. This is general information, not legal advice; always check the official authority before travelling.