If you use your own car on your job as an employee—and aren't reimbursed by your employer—you deserve a tax deduction. You might not get it, though, thanks to a squeeze introduced a few years ago by Congress. While self-employed taxpayers get to write-off all of their qualifying business automobile costs, employees must treat such costs as miscellaneous itemized expenses. You get to deduct such costs only to the extent they exceed 2% of your adjusted gross income. If your AGI is $75,000, that means the first $1,500 of your miscellaneous expenses don't count.
This restriction makes it critically important that you claim all legitimate miscellaneous expenses, including non-reimbursed car expenses. You get your choice of deducting actual car expenses or using the IRS standard mileage rate. For 2006, the rate is 44.5 cents a mile. Whether you use the standard rates or actual cost method, include parking and toll expenses incurred on the job. The interview will steer you to the biggest possible deduction.