An original bill to extend the Generalized System of Preferences.

Amends the Trade Act of 1974 to extend duty-free treatment under the Generalized System of Preferences through June 30, 2004.

Provides, upon request filed with the Customs Service, for the liquidation or reliquidation (refund of duties) on entries of articles to which duty-free treatment under the Generalized System of Preferences would have applied if such entry had been made on June 30, 1999, and that was made after such date, but before enactment of this Act.

Amends the Tariff Act of 1930 to require, with a specified exception, merchandise (including merchandise of different classes, types, and categories) withdrawn from a foreign trade zone during any seven-day period to be treated upon entry (at the option of the operator or user of the zone) as a single entry and a single release of merchandise for purposes of customs user fees. Authorizes the Secretary of the Treasury to require an operator or user of the zone to use an electronic data interchange to file such entries and to pay such user fees.

Amends the Internal Revenue Code to prohibit, in general, the use of the installment method of accounting for accrual method dispositions.