Itemized deduction

Under United States tax law, itemized deductions are eligible expenses that individual taxpayers can claim on federal income tax returns and which decrease their taxable income, and is claimable in place of a standard deduction, if available.

Most taxpayers are allowed a choice between the itemized deductions and the standard deduction. After computing their adjusted gross income (AGI), taxpayers can itemize deductions (from a list of allowable items) and subtract those itemized deductions (and any applicable personal exemption deductions) from their AGI amount to arrive at the taxable income. Alternatively, they can elect to subtract the standard deduction for their filing status (and any applicable personal exemption deduction) to arrive at the taxable income. In other words, the taxpayer may generally deduct the total itemized deduction amount, or the applicable standard deduction amount, whichever is greater.

The choice between the standard deduction and itemizing involves a number of considerations:

Deductions are reported in the tax year in which the eligible expenses were paid. For example, an annual membership fee for a professional association paid in December 2009 for year 2010 is deductible in year 2009.

There are a number of allowable deductions:

It is important to distinguish miscellaneous itemized deductions from other “normal” itemized deductions. The reason for this is because miscellaneous itemized deductions are subject to a 2% floor, a.k.a. the "2% Haircut." A taxpayer can only deduct the amount of miscellaneous itemized deductions that exceed 2% of their adjusted gross income. For example, if a taxpayer has adjusted gross income of $50,000 with $4,000 in miscellaneous itemized deductions, the taxpayer can only deduct $3,000, since the first $1,000 is below the 2% floor. There are 12 deductions listed in 26 U.S.C. § 67(b). These are NOT miscellaneous itemized deductions, and thus not subject to the 2% floor (although they may have their own rules). Any deduction not found in section 67(b) is a miscellaneous itemized deduction. Examples include:

If the taxpayer's adjusted gross income is above a threshold (or "applicable amount"), then the total allowable itemized deductions is reduced by the lesser of

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