Individual Tax Simplification Act of 2003

Individual Tax Simplification Act of 2003 - Amends the Internal Revenue Code to revise provisions concerning nonrefundable personal credits to provide that the aggregate amount of such credits allowed shall not exceed the amount of normal taxes and surtaxes.

Replaces the current three ranges for phaseout of the adoption, child, and Hope and Lifetime Learning tax credits with a single, uniform phaseout of such credits.

Mandates a deduction from gross income of 38 percent of a net capital gain for any taxable year for a taxpayer other than a corporation.

Repeals the overall limitation on itemized deductions, the phaseout of personal exemptions, and the alternative minimum tax on individuals.

Establishes an additional income tax, if the adjusted gross income of an individual exceeds specified thresholds, at a rate estimated by the Secretary of the Treasury which will result in the Individual Tax Simplification Act of 2001 being revenue neutral over the first 10 years after its enactment.