The Treasury Department and the Internal Revenue Service released the last set of final regulations PDF implementing the 100% additional first year depreciation deduction that allows businesses to write off the cost of most depreciable business assets in the year they are placed in service by the business. The 100% additional first year depreciation deduction was created in 2017 by the Tax Cuts and Jobs Act and generally applies to depreciable business assets with a recovery period of 20 years or less and certain other property. Machinery, equipment, computers, appliances and furniture generally qualify.