HB 621 -- Federal Income Tax Deduction Sponsor: Muschany Currently, the federal income tax deduction is limited to $5,000 for an individual taxpayer and $10,000 for combined taxpayers for individual income tax and to 50% of the federal income tax for corporations. Beginning January 1, 2008, this bill allows full deductibility from state income tax of all federal income tax liability.Copyright (c) Missouri House of Representatives