Section 179 allows eligible taxpayers to deduct in full certain business expenses, or "qualifying property," in a single tax year. Under Section 179, you can claim a deduction in the current year.179 deduction allows you to write off qualified expenses in the year the related business asset or property is placed in service. Section 179 is a tax deduction that benefits businesses who make qualified equipment or software purchases. Discover how it can benefit you today! Section 179 is a tax code section that allows businesses to deduct the total cost of equipment they bought during the year from their taxable income. How to report the recapture of Sec. 179 expense for passthrough entities at both the entity and owner levels. Section 179 deduction dollar limits.