You may check CBP web site for detail.
k8&FDz PKtU:Eg http://www.cbp.gov G:+16XCra r=csi The following is mentioned in U.S. Customs and Border Protection Declaration Form
!P|5#.eC HCc` Money And Other Monetary
J~J@ ]5/ Instruments
L~MpY{!3 You may bring into or take out of the country, including
8$ DwpJ by mail, as much money as you wish. However, if
;/Q6i
it is more than $10,000, you will need to report it to
N~g%wf@w CBP. Ask the CBP officer for the Currency Reporting
oa0X5}D Form (FinCen 105). The penalties for non-compliance
^pcRW44K can be severe.
SMq9j,k “Money” means monetary instruments and includes U.S.
^@_).:oX7 or foreign coins currently in circulation, currency, travelers’
@%B4;c checks in any form, money orders, and negotiable
[,7-w instruments or investment securities in bearer form.