Build America Bonds Act of 2005

Build America Bonds Act of 2005 - Amends the Internal Revenue Code to allow an income tax credit to a taxpayer holding a Build America bond on one of its credit allowance dates.

Defines a Build America bond as any bond issued by the Transportation Finance Corporation as part of an issue if the net spendable 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: (1) qualified project as any qualified highway project and qualified public transportation project proposed by one or more States and approved by the Transportation Finance Corporation; and (2) qualified highway project as any project of regional or national significance, freight intermodal connector project, multistate corridor program, and border planning and capacity improvement program.

Establishes the nonprofit Transportation Finance Corporation to: (1) issue Build America bonds for the financing of qualified projects; (2) establish and operate the Build America Trust Account; (3) leverage resources and stimulate public and private investment in transportation infrastructure; and (4) perform any other function the sole purpose of which is to carry out the financing of qualified projects through Build America bonds.