Depreciation - Cost Basis

Generally, to find the basis for depreciation:

  1. Multiply the cost or other basis of the property by the percentage of business/investment use.
  2. Subtract any section 179 expense deduction.
  3. Subtract any special depreciation allowance (50% and 30%).

For additional information please refer to the IRS Instructions for Form 4562 and IRS Publication 946 How to Depreciate Property.