Itemized Deduction Limitations. For tax year beginning after 2012, the itemized deduction limitation on itemized deductions, is reinstated with a starting threshold for those making $300,000 for joint filers and a surviving spouse, $275,000 for head of household, $250,000 for single filers, and $150,000 for married taxpayers filing separately. Thus, for taxpayers subject to the limitation, the total amount of their itemized deductions is reduced by 3% of the amount by which the taxpayer's adjusted gross income (AGI) exceeds the threshold amount, with the reduction not to exceed 80% of the otherwise allowable itemized deductions. These dollar amounts are inflation-adjusted for tax years after 2013.