US Department of the Treasury Financial Crimes Enforcement Network - FinCEN
http://www.fincen.gov/forms/bsa_forms/
Each person who physically transports, mails or ships, or causes to be physically transported, mailed, shipped or received, currency, travelers checks, and certain other monetary instruments in an aggregate amount exceeding $10,000 into or out of the United States must file a Report of International Transportation of Currency FinCEN Form 105 (CMIR).
Key Facts
As of April 1, 2013, financial institutions must use the new FinCEN reports, which are available only electronically through the BSA E-Filing System. FinCEN is no longer accepting legacy reports.
BSA E-Filing System
Additional Information
FinCEN Form 105 (CMIR)
Who it affects
US financial institutions, US businesses and US residents