Build America Bonds Act of 2003

Build America Bonds Act of 2003 - Amends the Internal Revenue Code to allow an income tax credit to a taxpayer holding a Build America bond on a credit allowance date of such bond.

Defines a Build America bond as any bond issued by the Build America Corporation as part of an issue if 95 percent or more of the proceeds from the sale of such issue are to be used for expenditures incurred for any qualified project, or for deposit in the Build America Trust Account for repayment of Build America bonds at maturity.

Defines qualified project as the financing of capital improvements for any transportation infrastructure project of any governmental unit or other person, including highways, transit systems, railroads, airports, ports, and inland waterways, proposed by a State and approved by the Build America Corporation.

Establishes the non-profit Build America Corporation to: (1) issue Build America bonds for the financing of qualified projects; (2) establish and operate the Build America Trust Account; and (3) perform any other function the sole purpose of which is to carry out the financing of qualified projects through Build America bonds.