Find out if you qualify for the Section 179 Deduction. This rule expires at the end of 2011 and allows you to write off the entire cost of the tangible personal property you use in your business. The maximum write-off is $500,000 in the first year, regardless of whether you made the purchase with cash or credit. Also, the $500,000 limit applies on a per-taxpayer basis and is expected to remain in effect through 2011. You are eligible for the deduction on a wide range of property, from computer software to office equipment.