[edit]
All payments for electronic travel authorization applications must be made by credit card or debit card when applying for or renewing an ESTA. ( ESTA - the Official U.S. Government Web Site ) The ESTA system currently accepts only the following credit/debit cards: MasterCard, VISA, American Express, and Discover. Your application will not be submitted for processing until all payment information is received.
http://www.cbp.gov/xp/cgov/newsroom/new ... 2010_2.xml