Tax Relief Guarantee Act of 2004

Tax Relief Guarantee Act of 2004 - Repeals the current termination date (December 31, 2010) of the Economic Growth and Tax Relief Reconciliation Act of 2001.

Amends the Internal Revenue Code to repeal: (1) the reductions in the amount of the child income tax credit scheduled for taxable years 2005 through 2009 and to set the amount of such credit at $1,000 for all taxable years after 2004; (2) the reductions in the basic standard deduction percentage for married couples filing joint tax returns scheduled for taxable years 2005 through 2008; (3) the reductions in the percentage applicable to the maximum taxable income in the 15 percent tax bracket for married couples filing joint tax returns scheduled for taxable years 2005 through 2007; and (4) the reduction in the income threshold amount for ten percent income tax rate eligibility scheduled for taxable years 2005 through 2007.

Repeals the current termination date (December 31, 2008) of provisions in the Jobs and Growth Tax Relief Reconciliation Act of 2003 reducing capital gains tax rates and allowing the taxation of dividends at capital gain tax rates.

Amends the Internal Revenue Code to: (1) set the dollar limitation for the expense deduction for depreciable business assets at $100,000 for all taxable years after 2004 and to permanently increase to $400,000 the threshold amount for determining reductions in the dollar limitation of such deduction; (2) increase the percentage of the additional depreciation allowance for property acquired after May 5, 2003, from 30 to 50 percent.